Exhibit 10.4

                               THIRD AMENDMENT TO
                                CREDIT AGREEMENT
 
     This Third Amendment to Credit Agreement (the "Third Amendment"), dated as
of February 14, 1997 is entered into by and between DRIL-QUIP, INC., a Texas
corporation ("Borrower"), and BANK ONE, TEXAS, NATIONAL ASSOCIATION, a national
banking association ("Lender").

                              W I T N E S S E T H:
                              - - - - - - - - - - 

     WHEREAS, pursuant to that certain Credit Agreement dated March 30, 1994 as
amended by that certain First Amendment to Credit Agreement dated December 20,
1994 and that certain Second Amendment to Credit Agreement dated December 13,
1995 (collectively, the "Credit Agreement"), Lender agreed to make available to
Borrower certain loans upon the terms and conditions and for the purposes
therein contained;

     WHEREAS, Borrower has requested that its revolving line of credit be
increased up to a maximum of TWENTY-FIVE MILLION AND NO/100 DOLLARS
($25,000,000.00) and extended to June 1, 1999 and Lender has agreed to such
increase and extension;

     WHEREAS, Borrower has requested Lender to make available to Borrower an
additional advancing line of credit of up to THREE MILLION AND NO/100 DOLLARS
($3,000,000.00) and Lender has agreed to make such loan to Borrower;

     WHEREAS, Borrower has requested Lender to consolidate certain term loans;

     WHEREAS, Borrower has requested Lender to make certain other changes to the
Credit Agreement; and

     WHEREAS, Borrower and Lender desire to amend the Credit Agreement so that
the Credit Agreement evidences such increase and extension of the revolving line
of credit, governs such additional advancing line of credit, consolidates
certain term loans and effects such other changes;

     NOW THEREFORE, the parties hereto agree as follows:

     1.   Amendments to Credit Agreement.  The Credit Agreement is modified as
follows:

          1.1  Wherever the term "Agreement" is used in the Credit Agreement,
               such term shall refer to the Credit Agreement as amended by this
               Third Amendment;

          1.2  Article I - Definitions.  The definition of the term "Commitment"
               is deleted in its entirety, and the following is substituted in
               place thereof:

                                      -1-

 
                    "Commitment" means (i) the commitment of Lender to make
                    available the Revolving Credit Loan hereunder, (ii) the
                    commitment of Lender to make available the Fourth Advancing
                    Credit Loan hereunder, (iii) the commitment of Lender to
                    make available the Term Loan hereunder and (iv) the
                    commitment of Lender to issue the Letters of Credit
                    hereunder.

          1.3  Article I - Definitions.  The definition of the term "Loans" is
               deleted in its entirety, and the following is substituted in
               place thereof:

                    "Loans" means, collectively, the Revolving Credit Loan, the
                    Fourth Advancing Credit Loan and the Term Loan, and "Loan"
                    means singly, the Revolving Credit Loan, the Fourth
                    Advancing Credit Loan or the Term Loan.

          1.4  Article I - Definitions.  The definition of the term "Notes" is
               deleted in its entirety, and the following is substituted in
               place thereof:

                    "Notes" shall mean the Revolving Credit Note, the Fourth
                    Advancing Credit Note and the Term Note and all extensions,
                    renewals and modifications thereof.

          1.5  Article I - Definitions. The definition of the term "Revolving
               Credit Committed Sum" is deleted in its entirety, and the
               following is substituted in place thereof:

                    "Revolving Credit Committed Sum" means TWENTY-FIVE MILLION
                    AND NO/100 DOLLARS ($25,000,000.00), as such amount may be
                    reduced pursuant to Section 2.06.

          1.6  Article I - Definitions.  The definition of the term "Revolving
               Credit Note" is deleted in its entirety, and the following is
               substituted in place thereof:

                    "Revolving Credit Note" means the promissory note in favor
                    of Lender in substantially the form of Exhibit O hereto, and
                    all extensions, renewals and modifications thereof.

          1.7  Article I - Definitions.  The definition of the term "Revolving
     Credit Termination Date" is deleted in its entirety, and the following is
     substituted in place thereof:

                                      -2-

 
                    "Revolving Credit Termination Date" means June 1, 1999, or
                    such earlier date as the Revolving Credit Commitment
                    terminates as provided in this Agreement.

          1.8  Article I - Definitions.  The definition of the term "Term Note"
               is deleted in its entirety, and the following is substituted in
               place thereof:

                    "Term Note" means the promissory note described in Section
                    4.01 hereof in favor of Lender in substantially the form of
                    Exhibit P hereto, and all extensions, renewals and
                    modifications thereof.

          1.9  Article I - Definitions.  Article I-Section 1.01 of the Agreement
               is hereby amended to add thereto the following definitions:

                    "Fourth Advancing Credit Commitment Fee" shall have the
                    meaning set forth in Section 3.28 hereof.
               
                    "Fourth Advancing Credit Commitment Period" means the period
                    commencing on February 14, 1997 and ending on the Fourth
                    Advancing Credit Termination Date.

                    "Fourth Advancing Credit Committed Sum" means THREE MILLION
                    AND NO/100 DOLLARS ($3,000,000.00), as such amount may be
                    reduced pursuant to Section 3.27 or otherwise.
               
                    "Fourth Advancing Credit Loan" means the Loan made by Lender
                    to Borrower, in one or more Advances, during the Fourth
                    Advancing Credit Commitment Period, pursuant to Section
                    3.22.

                    "Fourth Advancing Credit Note" means the promissory note in
                    favor of Lender in substantially the form of Exhibit Q
                    hereto, and all extensions, renewals and modifications
                    thereof.

                    "Fourth Advancing Credit Termination Date" means 11:00 a.m.
                    Houston, Texas, time on December 31, 1997, or such earlier
                    date as the Commitment to make Advances pursuant to Section
                    3.22 terminates as provided in this Agreement.

                                      -3-

 
          1.10 Article II.  Article 11 is hereby amended to substitute the
               following for Section 2.02 in its entirety:

                    Section 2.02. Revolving Credit Note.  The obligation of
                    Borrower to repay the Revolving Credit Loan shall be
                    evidenced by the Revolving Credit Note executed by Borrower,
                    payable to the order of Lender, in the principal amount of
                    the Revolving Credit Committed Sum and dated February 14,
                    1997.  The principal of the Revolving Credit Loan shall be
                    due and payable on the Revolving Credit Termination Date.
                    The Revolving Credit Loan shall bear interest prior to
                    maturity at a varying rate per annum equal from day to day
                    to the lesser of (a) the maximum rate permitted from day to
                    day by applicable law ("Maximum Rate"), including as to
                    Article 5069-1.04 Vernon's Texas Civil Statutes (and as the
                    same may be incorporated by reference in other Texas
                    statutes), but otherwise without limitation, that rate based
                    upon the "indicated rate ceiling", or (b) the sum of the
                    Bank One Texas Base Rate in effect from day to day plus one-
                    fourth of one percent (1/4%), each such change in the rate
                    of interest charged hereunder to become effective, without
                    notice to Borrower, on the effective date of each change in
                    the Bank One Texas Base Rate; provided, however, if at any
                    time the rate of interest specified in clause (b) preceding
                    shall exceed the Maximum Rate, thereby causing the interest
                    on the Revolving Credit Loan to be limited to the Maximum
                    Rate, then any subsequent reduction in the Bank One Texas
                    Base Rate shall not reduce the rate of interest on the
                    Revolving Credit Loan below the Maximum Rate until the
                    aggregate amount of interest accrued on the Revolving Credit
                    Loan equals the aggregate amount of interest which would
                    have accrued on the Revolving Credit Loan if the interest
                    rate specified in clause (b) preceding had at all times been
                    in effect.  Accrued and unpaid interest on the Revolving
                    Credit Loan shall be due and payable (a) quarterly in
                    arrears, on the 1st day of each successive April, July,
                    October and January commencing on April 1, 1997, until
                    payment in full of the outstanding principal under the
                    Revolving Credit Note and (b) on the Revolving Credit
                    Termination Date.  All past due principal and interest shall
                    bear interest at the Maximum Rate.

                                      -4-

 
          1.11 Article III.  Article III is hereby amended to delete Section
               3.15 through and including Section 3.21.

          1.12 Article III.  Article III is hereby amended to add thereto the
               following Sections:

                    Section 3.22.  Commitment for Fourth Advancing Credit Loan.
                    Subject to the terms and conditions of this Agreement, and
                    provided that no Default or Event of Default has occurred or
                    is continuing, Lender agrees to lend to Borrower, pursuant
                    to this Agreement, such amounts as the Borrower may request
                    in one or more Advances, from time to time during the Fourth
                    Advancing Credit Commitment Period to and including the
                    Fourth Advancing Credit Termination Date; provided, however,
                    that such Advances shall not exceed either singularly or
                    cumulatively the Fourth Advancing Credit Committed Sum; and
                    further provided that Lender shall not be obligated to make
                    such Loans pursuant to this Section 3.22 in excess of
                    eighty-five percent (85%) of the cost of improvements,
                    eighty percent (80%) of the cost of new equipment, eighty
                    percent (80%) of the cost of used, refurbished equipment and
                    sixty percent (60%) of the cost of used, unrefurbished
                    equipment; provided, however, that with respect to any used,
                    unrefurbished equipment, if Borrower should subsequently
                    refurbish such equipment, then the limit shall be increased
                    to eighty percent (80%) and Borrower may increase the amount
                    borrowed hereunder on account of such equipment to bring the
                    total to eighty percent (80%) of the cost of such equipment
                    and the cost of refurbishing such equipment.

                    Section 3.23.  Fourth Advancing Credit Note. The
                    obligation of Borrower to repay the Fourth Advancing Credit
                    Loan shall be evidenced by the Fourth Advancing Credit Note
                    executed by Borrower, payable to the order of Lender, in the
                    principal amount of the Fourth Advancing Credit Committed
                    Sum and dated February 14, 1997.  The principal of the
                    Fourth Advancing Credit Loan outstanding on the Fourth
                    Advancing Credit Termination Date, plus accrued and unpaid
                    interest thereon, shall be due and payable: (a) in three (3)
                    installments of accrued and unpaid interest only due and
                    payable on April 1, 1997, July 1, 1997 and October 1, 1997;
                    (b) in fifteen (15) installments each equal to ONE HUNDRED
                    THOUSAND 

                                      -5-

 
                    AND NO/100 DOLLARS ($100,000.00) of principal, together with
                    all accrued and unpaid interest, the first of such
                    installments being due and payable on or before January 1,
                    1998 and like installments being due and payable on the
                    first day of each succeeding third calendar month thereafter
                    through and including July 1, 2001; and (c) a final
                    installment shall be due on or before October 1, 2001 in an
                    amount equal to the remaining unpaid principal outstanding
                    on the Fourth Advancing Credit Loan together with all
                    accrued and unpaid interest. The Fourth Advancing Credit
                    Loan shall bear interest prior to maturity at a varying rate
                    per annum equal from day to day to the lesser of (a) the
                    Maximum Rate, or (b) the sum of the Bank One Base Rate in
                    effect from day to day plus one-half of one percent (1/2%),
                    each such change in the rate of interest charged hereunder
                    to become effective, without notice to Borrower, on the
                    effective date of each change in the Bank One Base Rate;
                    provided, however, if at any time the rate of interest
                    specified in clause (b) preceding shall exceed the Maximum
                    Rate, thereby causing the interest on the Fourth Advancing
                    Credit Loan to be limited to the Maximum Rate, then any
                    subsequent reduction in the Bank One Base Rate shall not
                    reduce the rate of interest on the Fourth Advancing Credit
                    Loan below the Maximum Rate until the aggregate amount of
                    interest accrued on the Fourth Advancing Credit Loan equals
                    the aggregate amount of interest which would have accrued on
                    the Fourth Advancing Credit Loan if the interest rate
                    specified in clause (b) preceding had at all times been in
                    effect. All past due principal and interest shall bear
                    interest at the Maximum Rate.

                    Section 3.24. Expiration of Commitment to Lend under Fourth
                    Advancing Credit.  The maximum obligation of Lender to make
                    Advances under Section 3.22 hereof shall not at any time
                    exceed, either singularly or cumulatively, the Fourth
                    Advancing Credit Committed Sum, and Lender shall have no
                    obligation to make additional Advances under Section 3.22
                    hereof and Lender's Commitment to lend to Borrower pursuant
                    to Section 3.22 hereof shall terminate and expire at 11:00
                    a.m., Houston, Texas time on the Fourth Advancing Credit
                    Termination Date; provided that Borrower's Obligations and
                    the Rights of Lender under the Loan Papers shall continue in
                    full force and effect until the Obligations have been paid
                    and performed in full.

                                      -6-

 
                    Section 3.25. Procedure for Borrowing Under the Fourth
                    Advancing Credit Loan.  During the Fourth Advancing Credit
                    Commitment Period, Borrower shall give Lender a written
                    notice executed on behalf of the Borrower by any Authorized
                    Financial Officer of the Borrower (the "Notice of Fourth
                    Advancing Credit Borrowing") of any proposed Borrowing under
                    the Fourth Advancing Credit Loan which shall be irrevocable.
                    Each Notice of Fourth Advancing Credit Borrowing shall be
                    received by Lender not later than 11:00 a.m., Houston, Texas
                    time, at least one (1) Business Day prior to any proposed
                    Borrowing requested by Borrower together with copies of
                    invoices for the equipment purchased or improvements
                    undertaken.  Each such Notice of Fourth Advancing Credit
                    Borrowing shall be substantially in the form of Exhibit R
                    attached hereto.  Lender, at its option, may from time to
                    time accept telephonic requests for Advances; provided that
                    Borrower shall promptly thereafter provide Lender with a
                    completed Notice of Fourth Advancing Credit Borrowing
                    together with copies of invoices for the equipment purchased
                    or improvements undertaken.  Lender is hereby authorized to
                    act in reliance upon a certificate of incumbency from
                    Borrower's Secretary or Assistant Secretary as to the
                    identity of the foregoing officers and their due appointment
                    and authorization to issue Borrowing requests and receive
                    proceeds of Advances hereunder on behalf of Borrower unless
                    and until Lender is in actual receipt of written notice by
                    Borrower of revocation of said appointment and
                    authorization.  Prior to 11:00 a.m. (Houston, Texas, time)
                    on each Borrowing Date and subject to the provisions of
                    Section 3.22, Lender shall make available to Borrower in
                    immediately available funds such requested Advance by
                    deposit to Borrower's deposit account maintained with Lender
                    or other reasonable disposition of such funds as Borrower
                    shall request in writing.  Lender may, and is hereby
                    authorized by Borrower to, endorse on the schedule attached
                    to the Fourth Advancing Credit Note or on a continuation of
                    such schedule attached to and made a part of such Fourth
                    Advancing Credit Note an appropriate notation evidencing the
                    date and amount of each Advance and payment and prepayment
                    by Borrower of the principal of and interest on the Fourth
                    Advancing Credit Loan evidenced by such Fourth Advancing
                    Credit Note, but the failure of Lender to make any such
                    endorsement or any incorrect endorsement shall not subject
                    Lender to any 

                                      -7-

 
                    liability hereunder and shall not limit or otherwise affect
                    the obligations of Borrower under such Fourth Advancing
                    Credit Note.

                    Section 3.26. Use of Proceeds of Fourth Advancing Credit
                    Loan.  The proceeds of the Advances comprising the Fourth
                    Advancing Credit Loan shall be used to pay (or reimburse
                    Borrower for amounts already spent by Borrower since October
                    1, 1996) for up to eighty-five percent (85%) of the costs of
                    Borrower for improvements on the realty described on
                    Schedule 3 attached to the Credit Agreement, up to eighty-
                    five percent (85%) of the cost of improvements, eighty
                    percent (80%) of the cost of new equipment, eighty percent
                    (80%) of the cost of used, refurbished equipment and sixty
                    percent (60%) of the cost of used, unrefurbished equipment;
                    provided, however, that with respect to any used,
                    unrefurbished equipment, if Borrower should subsequently
                    refurbish such equipment, then the limit shall be increased
                    to eighty percent (80%) and Borrower may increase the amount
                    borrowed hereunder on account of such equipment to bring the
                    total to eighty percent (80%) of the cost of such equipment
                    and the cost of refurbishing such equipment.

                    Section 3.27.  Reduction or Termination of Fourth Advancing
                    Committed Sum.  Borrower may at any time by giving at least
                    three (3) Business Days' notice in writing to Lender
                    terminate or reduce the Fourth Advancing Credit Committed
                    Sum; provided, however, that no such reduction of the Fourth
                    Advancing Credit Committed Sum shall be effective unless the
                    amount by which the Fourth Advancing Credit Committed Sum is
                    reduced shall be ONE HUNDRED THOUSAND AND NO/100
                    ($100,000.00) or an integral multiple thereof.  Once reduced
                    or terminated, the Fourth Advancing Credit Committed Sum may
                    not be increased or reinstated without the prior written
                    consent of Lender.

                    Section 3.28.  Fourth Advancing Credit Commitment Fee.
                    Borrower agrees to pay to Lender a fee (the "Fourth
                    Advancing Credit Commitment Fee") on the average daily
                    unused portion of the Fourth Advancing Credit Commitment,
                    from February 14, 1997 to and including the Fourth Advancing
                    Credit Termination Date, at the rate of one-half of one
                    percent (1/2%) per annum based on a 365 day year and 

                                      -8-

 
                    the actual number of days elapsed payable in arrears, on
                    April 1, 1997, July 1, 1997, October 1, 1997 and on the
                    Fourth Advancing Credit Termination Date.

          1.13 Article IV.  Article IV is hereby amended to substitute the
               following for Article IV in its entirety:

                                   Term Loan
                                   ---------

                    Section 4.01.  Commitment for Term Loan.  Subject to the
                    terms and conditions of this Agreement, and provided that no
                    Default or Event of Default has occurred and is continuing
                    on the Closing Date, Lender agrees to make the Term Loan to
                    Borrower under the Term Note, in the amount of TEN MILLION
                    SIX HUNDRED FIFTY-SEVEN THOUSAND AND NO/100 DOLLARS
                    ($10,657,000.00), which amount represents a renewal and
                    extension, in whole or in part, of the principal
                    indebtedness evidenced by:

                         (a) that certain Promissory Note dated October 1, 1995
                    in the principal amount of $11,622,000.00 executed by
                    Borrower and payable to the order of Lender; and

                         (b) that certain Promissory Note dated December 13,
                    1995 in the principal amount of $2,000,000.00 executed by
                    Borrower and payable to the order of Lender.

                    Section 4.02. Term Note.  The obligation of Borrower to
                    repay the Term Loan shall be evidenced by the Term Note
                    executed by Borrower, payable to the order of Lender, in the
                    principal amount of the Term Loan and dated February 14,
                    1997.  The principal of the Term Loan, plus accrued and
                    unpaid interest thereon, shall be due and payable in:

                         (a) nine (9) consecutive installments each equal to SIX
                    HUNDRED FORTY-NINE THOUSAND  AND NO/100 DOLLARS
                    ($649,000.00) of principal, together with all accrued and
                    unpaid interest, the first of such installments being due
                    and payable on or before April 1, 1997 and like installments
                    being due and payable on the first day of each succeeding
                    third calendar month thereafter through and including April
                    1, 1999; and

                                      -9-

 
                         (b) a final installment due and payable on July 1, 1999
                    in an amount equal to the remaining unpaid principal amount
                    outstanding on the Term Loan, together with all accrued and
                    unpaid interest.

                    The Term Loan shall bear interest prior to maturity at a
                    varying rate per annum equal from day to day to the lesser
                    of (a) the Maximum Rate or (b) the sum of the Bank One Texas
                    Base Rate in effect from day to day plus one-half of one
                    percent (1/2%), each such change in the rate of interest
                    charged hereunder to become effective, without notice to
                    Borrower, on the effective date of each change in the Bank
                    One Texas Base Rate; provided, however, if at any time the
                    rate of interest specified in clause (b) preceding shall
                    exceed the Maximum Rate, thereby causing the interest on the
                    Term Loan to be limited to the Maximum Rate, then any
                    subsequent reduction in the Bank One Texas Base Rate shall
                    not reduce the rate of interest on the Term Loan below the
                    Maximum Rate until the aggregate amount of interest accrued
                    on the Term Loan equals the aggregate amount of interest
                    which would have accrued on the Term Loan if the interest
                    rate specified in clause (b) preceding had at all times been
                    in effect.  All past due principal and interest shall bear
                    interest at the Maximum Rate.

          1.14 Article X.  Article X is hereby amended to substitute the
               following for Section 10.04 in its entirety:

                    Section 10.04.  Lease Obligations.  Permit aggregate
                    payments of Borrower and Subsidiaries under leases of real
                    or personal property to exceed ONE MILLION SIX HUNDRED
                    THOUSAND AND NO/100 DOLLARS ($1,600,000.00) in the aggregate
                    during any fiscal year.

     2.   Condition Precedent.  The obligation of Lender to make any Advances
pursuant to Sections 2.01 or 3.22 of the Agreement is subject to the condition
precedent that the Lender shall have received all of the following, each duly
executed and in form and substance satisfactory to Lender:

          (a)  Promissory Note dated February 14, 1997 in the principal amount
               of $25,000,000.00 executed by Borrower to the order of Lender,
               after execution and delivery being the Revolving Credit Note;

                                      -10-

 
          (b)  Promissory Note dated February 14, 1997 in the principal amount
               of $10,657,000.00 executed by Borrower to the order of Lender,
               after execution and delivery being the Term Note;

          (c)  Promissory Note dated February 14, 1997 in the principal amount
               of $3,000,000.00 executed by Borrower to the order of Lender,
               after execution and delivery being the Fourth Advancing Credit
               Note;

          (d)  Ratifications or amendments of existing Security Documents and/or
               new Security Documents as may be requested by Lender to continue
               or establish a Lien in favor or for the benefit of Lender in or
               against (i) all of Borrower's accounts, accounts receivable,
               equipment, machinery, fixtures, raw materials, work-in-process,
               inventory, chattel paper, documents, instruments and general
               intangibles, whether now owned or hereafter acquired, and all
               products and proceeds thereof, and (ii) the realty described in
               Schedule 3 of the Credit Agreement, the appurtenances thereto and
               improvements thereon;

          (e)  Certified copies of resolutions of the Board of Directors of
               Borrower authorizing or ratifying the execution, delivery and
               performance, respectively, of those of this Fourth Amendment, the
               Revolving Credit Note, the Fourth Advancing Second Credit Note,
               the Term Note and all other documents provided for in this Third
               Amendment to which each is a party;

          (f)  The articles of incorporation of Borrower certified by the
               Secretary of State of the State of incorporation, and dated
               reasonably near the date of this Third Amendment;

          (g)  Certificates of the appropriate government officials of the
               jurisdiction of incorporation of Borrower as to its existence and
               good standing, dated reasonably near the date of this Third
               Amendment; and

          (h)  A favorable opinion of legal counsel to Borrower.

     3.   Representations and Warranties.  The representations and warranties
made in Article VIII of the Credit Agreement by Borrower to Lender are true and
correct as of the date of execution of this Third Amendment.

     4.   Defined Terms.  Words and terms used herein which are defined in the
Credit Agreement are used herein as defined in the Credit Agreement, except as
specifically modified by the terms of this Third Amendment.  Any of the terms
used in this Third Amendment which are not defined in the Credit Agreement shall
be used therein as herein defined.

                                      -11-

 
     5.   Preservation of the Credit Agreement.  Except as specifically modified
by the terms of this Third Amendment, all of the terms, provisions, covenants,
warranties and agreements contained in the Credit Agreement shall remain in full
force and effect.

     6.   Applicable Law.  This Third Amendment shall be deemed to be a contract
made under, and shall be construed in accordance with, the laws of the State of
Texas.

     7.   Entire Agreement.  The Credit Agreement as amended by this Third
Amendment and the other Loan Papers contain the entire agreement between the
parties relating to the transactions contemplated hereby.  All prior or
contemporaneous understandings, representations, statements and agreements,
whether written or oral, are merged herein and superseded by the Credit
Agreement as amended by this Third Amendment.  THIS WRITTEN AGREEMENT AND THE
OTHER LOAN PAPERS REPRESENT THE FINAL AGREEMENT BETWEEN THE PARTIES AND MAY NOT
BE CONTRADICTED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS OR SUBSEQUENT ORAL
AGREEMENTS OF THE PARTIES.  THERE ARE NO UNWRITTEN ORAL AGREEMENTS BETWEEN THE
PARTIES.

     IN WITNESS WHEREOF, the parties have executed this Third Amendment as of
the date first above written.

                                    BORROWER:

                                    DRIL-QUIP, INC.


                                    By:
                                       -------------------------
                                         J. Mike Walker
                                         Vice President

                                    LENDER:

                                    BANK ONE, TEXAS, NATIONAL
                                         ASSOCIATION


                                    By:
                                         -----------------------
                                         Charles Kingswell-Smith
                                         Vice President

                                      -12-

 
                                   EXHIBIT O

                                PROMISSORY NOTE


$25,000,000.00            Houston, Texas        February ___, 1997


          FOR VALUE RECEIVED, the undersigned, DRIL-QUIP, INC., a Texas
corporation ("Maker"), hereby promises to pay to the order of BANK ONE, TEXAS,
NATIONAL ASSOCIATION, a national banking association ("Payee"), at its offices
at 910 Travis, Houston, Harris County, Texas, on June 1, 1999, in lawful money
of the United States of America, the principal sum of TWENTY-FIVE MILLION AND
NO/100 DOLLARS ($25,000,000.00), or so much thereof as may be advanced and
outstanding hereunder, together with interest on the outstanding principal
balance hereof, at a varying rate per annum which shall from day to day be equal
to the lesser of (a) the maximum rate permitted by applicable law as the same
exists from day to day during the term hereof ("Maximum Rate"), including, as to
Article 5069-1.04, Vernon's Texas Civil Statutes (and as the same may be
incorporated by reference in other Texas statutes), but otherwise without
limitation, that rate based upon the "indicated rate ceiling" or (b) the sum of
the Bank One Base Rate (hereinafter defined) of Payee in effect from day to day
plus one-fourth of one percent (1/4%), each such change in the rate of interest
charged hereunder to become effective, without notice to Maker, on the effective
date of each change in the Bank One Base Rate; provided however, if at any time
the rate of interest specified in clause (b) preceding shall exceed the Maximum
Rate, thereby causing the interest rate hereon to be limited to the Maximum
Rate, then any subsequent reduction in the Bank One Base Rate will not reduce
the rate of interest hereon below the Maximum Rate until the total amount of
interest accrued hereon equals the amount of interest which would have accrued
hereon if the rate specified in clause (b) preceding had at all times been in
effect.

     Accrued and unpaid interest shall be due and payable quarterly in arrears
during the term hereof, on the 1st day of each successive April, July, October
and January commencing on April 1, 1997, until payment in full of the
outstanding principal hereunder.  All principal hereof, together with all
accrued and unpaid interest thereon, shall be due and payable on maturity.  All
past due principal and interest shall bear interest at the Maximum Rate.

     Whenever any payment hereunder shall be stated to be due on a day that is
not a day Payee is open for business, such payment may be made on the next
succeeding day Payee is open for business and interest shall continue to accrue
during such extension.

     As used herein, the term "Bank One Base Rate" means, at any time the lesser
of (i) the rate of interest per annum then most recently established by Payee as
its Bank One Base Rate in effect 

                                                               --------------
                                                               Initialled for
                                                               Identification

                             Page 1 of a 4 Page Note

 
from day to day, with each change in the rate of interest charged as the Bank
One Base Rate to become effective, without notice to Maker, on the effective
date of each change in the Bank One Base Rate, such Bank One Base Rate to be
computed on the basis of a year composed of 365 days for the actual number of
days elapsed (including the first day but excluding the last day) or (ii) the
Maximum Rate (as herein defined).

     This note is the Revolving Credit Note provided for and as defined in that
certain Credit Agreement dated March 30, 1994 as amended by First Amendment to
Credit Agreement dated December 20, 1994, Second Amendment to Credit Agreement
dated December 13, 1995 and that certain Third Amendment to Credit Agreement
dated of even date herewith by and among Maker and Payee (such instruments as
the same may be amended or modified from time to time, are hereinafter referred
to as the "Agreement").

     Maker may prepay the principal of this note upon the terms and conditions
specified in the Agreement.  Maker may borrow, repay and reborrow hereunder upon
the terms and conditions specified in the Agreement.

     Notwithstanding anything to the contrary contained herein, no provisions of
this note shall require the payment or permit the collection of interest in
excess of the Maximum Rate.  If any excess of interest in such respect is herein
provided for, or shall be adjudicated to be so provided, in this note or
otherwise in connection with this loan transaction the provisions of this
paragraph shall govern and prevail, and neither Maker nor the sureties,
guarantors, successors or assigns of Maker shall be obligated to pay the excess
amount of such interest, or any other excess sum paid for the use, forbearance
or detention of sums loaned pursuant hereto.  If for any reason interest in
excess of the Maximum Rate shall be deemed charged, required or permitted by any
court of competent jurisdiction, any such excess shall be applied as a payment
and reduction of the principal of indebtedness evidenced by this note; and, if
the principal amount hereof has been paid in full, any remaining excess shall
forthwith be paid to Maker.

     If default be made in the payment of principal or interest under this note
and such default shall continue for three (3) Business Days after notice thereof
to Maker pursuant to the Agreement, as defined in the Agreement, or upon the
occurrence of any other Event of Default as such term is defined in the
Agreement, the holder hereof may, at its option, declare the entire unpaid
principal of and accrued interest on this note immediately due and payable
without additional notice, demand or presentment, all of which are hereby
waived, and upon such declaration, the same shall become and shall be
immediately due and payable, and the holder hereof shall have the right to
foreclose or otherwise enforce all liens or security interests securing any sum
or sums owed by the holder hereof to Maker.  Failure of the holder hereof to
exercise this option shall not constitute a waiver of the right to exercise the
same upon the occurrence of a subsequent Event of Default.


                                                             ______________
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                                                             Identification

                            Page 2 of a 4 Page Note

 
     If the holder hereof expends any effort in any attempt to enforce payment
of all or any part or installment of any sum due the holder hereunder, or if
this note is placed in the hands of an attorney for collection, or if it is
collected through any legal proceedings, Maker agrees to pay all collection
costs and fees incurred by the holder, including reasonable attorneys' fees.

     This note is performable in Houston, Harris County, Texas, and Maker and
each surety, guarantor, endorser and other party ever liable for payment of any
sums of money payable on this note, jointly and severally waive the right to be
sued hereon elsewhere.  This note shall be governed by and construed in
accordance with the laws of the state of Texas and the applicable laws of the
United States of America.

     Maker and each surety, guarantor, endorser and other party ever liable for
payment of any sums of money payable on this note jointly and severally waive
presentment and demand for payment, protest, notice of protest and non-payment
of dishonor, notice of acceleration, notice of intent to accelerate, notice of
intent to demand, diligence in collecting, and grace, and consent to all
extensions without notice for any period or periods of time and partial
payments, before or after maturity, without prejudice to the holder.  Maker
acknowledges and understands that under the laws of the State of Texas, unless
waived, Maker has the right to notice of Payee's intent to accelerate the
indebtedness evidenced by this note, the right to notice of the actual
acceleration of the indebtedness evidenced by this note, and the right to
presentment of this note by Payee's demand for payment. Maker acknowledges that
it understands that it can waive these rights and by Maker's execution of this
note it agrees to waive its right to notice of intent to accelerate, its right
to notice of acceleration, and its right to presentment or other demand for
payment.  The holder shall similarly have the right to deal in any way, at any
time, without one or more of the foregoing parties without notice to any other
party, and to grant any such party and extensions of time for payment of any of
said indebtedness, or to release part or all of the collateral securing this
note, or to grant any other indulgences or forbearances whatsoever, without
notice to any other party and without in any way affecting the personal
liability of any party hereunder.

     This note is executed in renewal and extension, but not in novation or
discharge, of that certain Promissory Note dated October 1, 1995, in the
original principal amount of $20,000,000.00, executed by Maker for the benefit
of Payee.

     Maker hereby authorizes the holder hereof to endorse on the Schedule
attached to this note or any continuation thereof, all advances made to Maker
hereunder and all payments made on account of the principal thereof, which
endorsements shall be prima facie evidence as to the outstanding principal
amount of this note; provided, however, any failure by the holder hereof to make
endorsement shall not limit or otherwise affect the obligations of Maker under
the Agreement or this note.



                                                               --------------
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                                                               Identification

                            Page 3 of a 4 Page Note

 
                                    DRIL-QUIP, INC.



                                    By:
                                         ------------------------------------
                                         J. Mike Walker, Vice President



                                                               ---------------
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                                                               Identification


                            Page 4 of a 4 Page Note

 
                                   EXHIBIT P

                                PROMISSORY NOTE


$10,657,000.00            Houston, Texas        February ___, 1997


          FOR VALUE RECEIVED, the undersigned, DRIL-QUIP, INC., a Texas
corporation ("Maker"), hereby promises to pay to the order of BANK ONE, TEXAS,
NATIONAL ASSOCIATION, a national banking association ("Payee"), at its offices
at 910 Travis, Houston, Harris County, Texas, in lawful money of the United
States of America, the principal sum of TEN MILLION SIX HUNDRED FIFTY-SEVEN
THOUSAND AND NO/100 DOLLARS ($10,657,000.00), plus accrued and unpaid interest
thereon as hereinafter calculated, as follows:

          (a) nine (9) quarterly installments each in the principal amount of
     SIX HUNDRED FORTY-NINE THOUSAND AND NO/100 DOLLARS ($649,000.00), together
     with all accrued and unpaid interest, with the first of such installments
     due and payable on April 1, 1997, and like successive installments of
     principal plus accrued and unpaid interest due and payable on the 1st day
     of each succeeding July, October, January and April thereafter, through and
     including April 1, 1999; and

          (b) a tenth (10th) and final installment in the amount of all
          outstanding principal, plus accrued and unpaid interest, due and
          payable on the maturity of this note, July 1, 1999.

     The outstanding principal balance hereof shall bear interest prior to
maturity at a varying rate per annum which shall from day to day be equal to the
lesser of (a) the maximum rate permitted by applicable law as the same exists
from day to day during the term hereof ("Maximum Rate"), including, as to
Article 5069-1.04, Vernon's Texas Civil Statutes (and as the same may be
incorporated by reference in other Texas statutes), but otherwise without
limitation, that rate based upon the "indicated rate ceiling" or (b) the sum of
the Bank One Base Rate (hereinafter defined) of Payee in effect from day to day
plus one-half of one percent (1/2%), each such change in the rate of interest
charged hereunder to become effective, without notice to Maker, on the effective
date of each change in the Bank One Base Rate; provided however, if at any time
the rate of interest specified in clause (b) preceding shall exceed the Maximum
Rate, thereby causing the interest rate hereon to be limited to the Maximum
Rate, then any subsequent reduction in the Bank One Base Rate will not reduce
the rate of interest hereon below the Maximum Rate until the total amount of
interest accrued hereon equals the amount of interest which would have accrued
hereon if the rate specified in clause (b) preceding had at all times been in
effect.  All past due principal and interest shall bear interest at the Maximum
Rate.

                                                               --------------
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                                                               Identification

                            Page 1 of a 4 Page Note

 
     As used herein, the term "Bank One Base Rate" means, at any, time the
lesser of (i) the rate of interest per annum then most recently established by
Payee as its Bank One Base Rate in effect from day to day, with each change in
the rate of interest charged as the Bank One Base Rate to become effective,
without notice to Maker, on the effective date of each change in the Bank One
Base Rate, such Bank One Base Rate to be computed on the basis of a year
composed of 365 days for the actual number of days elapsed (including the first
day but excluding the last day) or (ii) the Maximum Rate (as herein defined).

     This note is the Term Note provided for and as defined in that certain
Credit Agreement dated March 30, 1994 as amended by that certain First Amendment
to Credit Agreement dated December 20, 1994, that certain Second Amendment to
Credit Agreement dated December 13, 1995 and that certain Third Amendment to
Credit Agreement dated of even date herewith by and among Maker and Payee (such
instrument as the same may be amended or modified from time to time, is
hereinafter referred to as the "Agreement").

     Maker may prepay the principal of this note upon the terms and conditions
specified in the Agreement.

     Notwithstanding anything to the contrary contained herein, no provisions of
this note shall require the payment or permit the collection of interest in
excess of the Maximum Rate.  If any excess of interest in such respect is herein
provided for, or shall be adjudicated to be so provided, in this note or
otherwise in connection with this loan transaction the provisions of this
paragraph shall govern and prevail, and neither Maker nor the sureties,
guarantors, successors or assigns of Maker shall be obligated to pay the excess
amount of such interest, or any other excess sum paid for the use, forbearance
or detention of sums loaned pursuant hereto.  If for any reason interest in
excess of the Maximum Rate shall be deemed charged, required or permitted by any
court of competent jurisdiction, any such excess shall be applied as a payment
and reduction of the principal of indebtedness evidenced by this note; and, if
the principal amount hereof has been paid in full, any remaining excess shall
forthwith be paid to Maker.

     If default be made in the payment of principal or interest under this note
and such default shall continue for three (3) Business Days after notice thereof
to Maker pursuant to the Agreement, as defined in the Agreement, or upon the
occurrence of any other Event of Default, as such term is defined in the
Agreement, the holder hereof may, at its option, declare the entire unpaid
principal of and accrued interest on this note immediately due and payable
without additional notice, demand or presentment, all of which are hereby
waived, and upon such declaration, the same shall become and shall be
immediately due and payable, and the holder hereof shall have the right to
foreclose or otherwise enforce all liens or security interests securing any sum
or sums owed by the holder hereof to Maker.  Failure of the holder hereof to
exercise this option shall not constitute a waiver of the right to exercise the
same upon the occurrence of a subsequent Event of Default.


                                                               ----------------
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                                                               Identification

                            Page 2 of a 4 Page Note

 
     If the holder hereof expends any effort in any attempt to enforce payment
of all or any part or installment of any sum due the holder hereunder, or if
this note is placed in the hands of an attorney for collection, or if it is
collected through any legal proceedings, Maker agrees to pay all collection
costs and fees incurred by the holder, including reasonable attorneys' fees.

     This note is performable in Houston, Harris County, Texas, and Maker and
each surety, guarantor, endorser and other party ever liable for payment of any
sums of money payable on this note, jointly and severally waive the right to be
sued hereon elsewhere.  This note shall be governed by and construed in
accordance with the laws of the state of Texas and the applicable laws of the
United States of America.

     Maker and each surety, guarantor, endorser and other party ever liable for
payment of any sums of money payable on this note jointly and severally waive
presentment and demand for payment, protest, notice of protest and non-payment
of dishonor, notice of acceleration, notice of intent to accelerate, notice of
intent to demand, diligence in collecting, and grace, and consent to all
extensions without notice for any period or periods of time and partial
payments, before or after maturity, without prejudice to the holder.  Maker
acknowledges and understands that under the laws of the State of Texas, unless
waived, Maker has the right to notice of Payee's intent to accelerate the
indebtedness evidenced by this note, the right to notice of the actual
acceleration of the indebtedness evidenced by this note, and the right to
presentment of this note by Payee's demand for payment. Maker acknowledges that
it understands that it can waive these rights and by Maker's execution of this
note it agrees to waive its right to notice of intent to accelerate, its right
to notice of acceleration, and its right to presentment or other demand for
payment.  The holder shall similarly have the right to deal in any way, at any
time, without one or more of the foregoing parties without notice to any other
party, and to grant any such party and extensions of time for payment of any of
said indebtedness, or to release part or all of the collateral securing this
note, or to grant any other indulgences or forbearances whatsoever, without
notice to any other party and without in any way affecting the personal
liability of any party hereunder.

     This note is executed in renewal and rearrangement but not in novation or
discharge, of (i) that certain Promissory Note dated October 1, 1995 in the
original principal amount of $11,622,000.00, executed by Maker for the benefit
of Payee, and (ii) that certain Promissory Note dated December 13, 1995 in the
original principal amount of $2,000,000.00, executed by Maker for the benefit of
Payee.

     Maker hereby authorizes the holder hereof to endorse on the Schedule
attached to this note or any continuation thereof, all advances made to Maker
hereunder and all payments made on account of the principal thereof which
endorsements shall be prima facie evidence as to the outstanding principal
amount of this note; provided, however, any failure by the holder hereof to make
endorsement shall not limit or otherwise affect the obligations of Maker under
the Agreement or this note.


                                                               ---------------
                                                               Initialled for
                                                               Identification

                            Page 3 of a 4 Page Note

 
                                    DRIL-QUIP, INC.



                                    By:
                                         -------------------------------
                                         J. Mike Walker, Vice President




                                                               ---------------
                                                               Initialled for
                                                               Identification


                            Page 4 of a 4 Page Note

 
                                   EXHIBIT Q
                                   ---------

                                PROMISSORY NOTE


$3,000,000.00             Houston, Texas        February ___, 1997


          FOR VALUE RECEIVED, the undersigned, DRIL-QUIP, INC., a Texas
corporation ("Maker"), hereby promises to pay to the order of BANK ONE, TEXAS,
NATIONAL ASSOCIATION, a national banking association ("Payee"), at its offices
at 910 Travis, Houston, Harris County, Texas, in lawful money of the United
States of America, the principal sum of THREE MILLION AND NO/100 DOLLARS
($3,000,000.00), or so much thereof as may be advanced and outstanding
hereunder, plus accrued and unpaid interest thereon as hereinafter calculated,
as follows:

          (a) in three (3) installments of accrued and unpaid interest due and
     payable on April 1, 1997, July 1, 1997 and October 1, 1997;

          (b) fifteen (15) quarterly installments each in the amount of ONE
     HUNDRED THOUSAND AND NO/100 DOLLARS ($100,000.00) of principal, together
     with all accrued and unpaid interest, with the first of such installments
     due and payable on January 1, 1998, and like successive installments of
     principal plus accrued and unpaid interest due and payable on the 1st day
     of each succeeding April, July, October and January thereafter, through and
     including July 1, 2001; and

          (c) a final installment in the amount of all outstanding principal,
     plus accrued and unpaid interest due and payable on the maturity of this
     note, October 1, 2001.

     Whenever any payment hereunder shall be stated to be due on a day that is
not a day Payee is open for business, such payment may be made on the next
succeeding day Payee is open for business and interest shall accrue during such
extension.

     The outstanding principal balance hereof shall bear interest prior to
maturity at a varying rate per annum which shall from day to day be equal to the
lesser of (a) the maximum rate permitted by applicable law as the same exists
from day to day during the term hereof ("Maximum Rate"), including, as to
Article 5069-1.04, Vernon's Texas Civil Statutes (and as the same may be
incorporated by reference in other Texas statutes), but otherwise without
limitation, that rate based upon the "indicated rate ceiling" or (b) the sum of
the Bank One Base Rate (hereinafter defined) of Payee in effect from day to day
plus one-half of one percent (1/2%), each such change in the rate of interest
charged hereunder to become effective, without notice to Maker, on the effective
date of 


                                                               ----------------
                                                               Initialled for
                                                               Identification


                            Page 1 of a 4 Page Note

 
each change in the Bank One Base Rate; provided however, if at any time the rate
of interest specified in clause (b) preceding shall exceed the Maximum Rate,
thereby causing the interest rate hereon to be limited to the Maximum Rate, then
any subsequent reduction in the Bank One Base Rate will not reduce the rate of
interest hereon below the Maximum Rate until the total amount of interest
accrued hereon equals the amount of interest which would have accrued hereon if
the rate specified in clause (b) preceding had at all times been in effect. All
past due principal and interest shall bear interest at the Maximum Rate.

     As used herein, the term "Bank One Base Rate" means, at any, time the
lesser of (i) the rate of interest per annum then most recently established by
Payee as its Bank One Base Rate in effect from day to day, with each change in
the rate of interest charged as the Bank One Base Rate to become effective,
without notice to Maker, on the effective date of each change in the Bank One
Base Rate, such Bank One Base Rate to be computed on the basis of a year
composed of 365 days for the actual number of days elapsed (including the first
day but excluding the last day) or (ii) the Maximum Rate (as herein defined).

     This note is the Fourth Advancing Credit Note provided for and as defined
in that certain Credit Agreement dated March 30, 1994 as amended by that certain
First Amendment to Credit Agreement dated December 20, 1994, that certain Second
Amendment to Credit Agreement dated February 13, 1997 and that certain Third
Amendment to Credit Agreement date of even date herewith by and between Maker
and Payee (such instruments as the same may be further amended or modified from
time to time, are hereinafter referred to as the "Agreement").

     Maker may prepay the principal of this note upon the terms and conditions
specified in the Agreement.

     Notwithstanding anything to the contrary contained herein, no provisions of
this note shall require the payment or permit the collection of interest in
excess of the Maximum Rate.  If any excess of interest in such respect is herein
provided for, or shall be adjudicated to be so provided, in this note or
otherwise in connection with this loan transaction the provisions of this
paragraph shall govern and prevail, and neither Maker nor the sureties,
guarantors, successors or assigns of Maker shall be obligated to pay the excess
amount of such interest, or any other excess sum paid for the use, forbearance
or detention of sums loaned pursuant hereto.  If for any reason interest in
excess of the Maximum Rate shall be deemed charged, required or permitted by any
court of competent jurisdiction, any such excess shall be applied as a payment
and reduction of the principal of indebtedness evidenced by this note; and, if
the principal amount hereof has been paid in full, any remaining excess shall
forthwith be paid to Maker.

     If default be made in the payment of principal or interest under this note
and such default shall continue for three (3) Business Days after notice thereof
to Maker pursuant to the Agreement, as defined in the Agreement, or upon the
occurrence of any other Event of Default, as such term is 


                                                               ----------------
                                                               Initialled for
                                                               Identification


                            Page 2 of a 4 Page Note

 
defined in the Agreement, the holder hereof may, at its option, declare the
entire unpaid principal of and accrued interest on this note immediately due and
payable without additional notice, demand or presentment, all of which are
hereby waived, and upon such declaration, the same shall become and shall be
immediately due and payable, and the holder hereof shall have the right to
foreclose or otherwise enforce all liens or security interests securing any sum
or sums owed by the holder hereof to Maker. Failure of the holder hereof to
exercise this option shall not constitute a waiver of the right to exercise the
same upon the occurrence of a subsequent Event of Default.

     If the holder hereof expends any effort in any attempt to enforce payment
of all or any part or installment of any sum due the holder hereunder, or if
this note is placed in the hands of an attorney for collection, or if it is
collected through any legal proceedings, Maker agrees to pay all collection
costs and fees incurred by the holder, including reasonable attorneys' fees.

     This note is performable in Houston, Harris County, Texas, and Maker and
each surety, guarantor, endorser and other party ever liable for payment of any
sums of money payable on this note, jointly and severally waive the right to be
sued hereon elsewhere.  This note shall be governed by and construed in
accordance with the laws of the state of Texas and the applicable laws of the
United States of America.

     Maker and each surety, guarantor, endorser and other party ever liable for
payment of any sums of money payable on this note jointly and severally waive
presentment and demand for payment, protest, notice of protest and non-payment
of dishonor, notice of acceleration, notice of intent to accelerate, notice of
intent to demand, diligence in collecting, and grace, and consent to all
extensions without notice for any period or periods of time and partial
payments, before or after maturity, without prejudice to the holder.  Maker
acknowledges and understands that under the laws of the State of Texas, unless
waived, Maker has the right to notice of Payee's intent to accelerate the
indebtedness evidenced by this note, the right to notice of the actual
acceleration of the indebtedness evidenced by this note, and the right to
presentment of this note by Payee's demand for payment. Maker acknowledges that
it understands that it can waive these rights and by Maker's execution of this
note it agrees to waive its right to notice of intent to accelerated, its right
to notice of acceleration, and its right to presentment or other demand for
payment.  The holder shall similarly have the right to deal in any way, at any
time, without one or more of the foregoing parties without notice to any other
party, and to grant any such party and extensions of time for payment of any of
said indebtedness, or to release part or all of the collateral securing this
note, or to grant any other indulgences or forbearances whatsoever, without
notice to any other party and without in any way affecting the personal
liability of any party hereunder.

     Maker hereby authorizes the holder hereof to endorse on the Schedule
attached to this note or any continuation thereof, all advances made to Maker
hereunder and all payments made on account of the principal thereof, which
endorsements shall be prima facie evidence as to the outstanding principal
amount of this note; provided, however, any failure by the holder hereof to 


                                                               ---------------
                                                               Initialled for
                                                               Identification

                            Page 3 of a 4 Page Note

 
make endorsement shall not limit or otherwise affect the obligations of Maker
under the Agreement or this note.

                                    DRIL-QUIP, INC.



                                    By:
                                         -------------------------------
                                         J. Mike Walker, Vice President


                                                              -----------------
                                                              Initialled for
                                                              Identification

                            Page 4 of a 4 Page Note

 
                                   EXHIBIT R
                                   ---------

                       FORM OF NOTICE OF FOURTH ADVANCING
                                CREDIT BORROWING


                            _________________, 19___


BANK ONE, TEXAS, NATIONAL ASSOCIATION
910 Travis Street
Houston, Texas 77002

Attention: ____________________

Gentlemen:

     The undersigned is an Authorized Financial Officer of Dril-Quip, Inc., a
Texas corporation ("Borrower") , and as such is authorized to make and deliver
this Notice of Fourth Advancing Credit Borrowing pursuant to Section 3.25 of
that certain Credit Agreement dated March 30, 1994 as amended by that certain
First Amendment to Credit Agreement dated December 20, 1994, that certain Second
Amendment to Credit Agreement dated December 13, 1995 and that certain Third
Amendment to Credit Agreement dated February 14, 1997 (as may be further amended
from time to time, the "Credit Agreement"), by and between BANK ONE, TEXAS,
NATIONAL ASSOCIATION ("Lender") and Borrower.  All terms defined in the Credit
Agreement shall have the same meaning herein.  Borrower hereby requests a
Borrowing under the Fourth Advancing Credit Loan from Lender in accordance with
Section 3.25 of the Credit Agreement.

     In connection with the foregoing and pursuant to the terms and provisions
of the Credit Agreement, the undersigned hereby certifies that:

          (i) Except as disclosed in Schedule I attached hereto, the
     representations and warranties contained in Article VIII of the Credit
     Agreement are true and correct in all material respects at and as of the
     date hereof as though made as of the date hereof.

          (ii) No Default or Event of Default has occurred and is continuing.

          (iii)  The amount of the Fourth Advancing Credit Loan to be made
     pursuant to this request, either singularly or together with other
     Borrowings previously made under Section 3.22 of the Credit Agreement does
     not exceed the Fourth Advancing Credit Committed Sum.

 
Bank One, Texas, National Association
___________________, 19________
Page 2



          (iv) [Proceeds from this Borrowing will be used to pay for up to
     eighty-five percent (85%) of the costs of improvements to the realty
     described on Schedule 3 to the Credit Agreement].

          [Proceeds from this Borrowing will be used to pay for up to sixty
     percent (60%) of the cost of certain used, unrefurbished equipment].

          [Proceeds from this Borrowing will be used to pay for up to eighty
     percent (80%) of the cost of certain new equipment].

          [Proceeds from this Borrowing will be used to pay for up to eighty
     percent (80%) of the costs of certain used, refurbished equipment].

          (v) [Attached hereto are copies of invoices for such materials and
     work performed].

          [Attached hereto are copies of invoices for such equipment purchased].

          (vi) All information supplied herein is true and accurate as of the
     date hereof.

The Borrowing Date shall be ___________________________, 19_____.

                                    DRIL-QUIP, INC.

                                                            By:________________
                                                            Name:______________
                                                            Title:_____________