EXHIBIT 3.6

                          CERTIFICATE OF DESIGNATION
                          OF SERIES K PREFERRED STOCK
                                      OF
                           BAKER HUGHES INCORPORATED

     Baker Hughes Incorporated, a corporation organized and existing under the 
General Corporation Law of the State of Delaware,

     DOES HEREBY CERTIFY:

     That, pursuant to authority conferred upon the Board of Directors by the 
Restated Certificate of Incorporation of said Corporation, and pursuant to the 
provisions of Section 151 of Title 8 of the Delaware Code of 1953, as amended, 
said Board of Directors, at a meeting thereof duly and regularly held on 
December 6, 1989, adopted recitals and resolutions providing for the powers, 
designations, preferences and relative, participating, optional or other rights,
and the qualifications, limitations or restrictions thereof, of certain series 
of preferred stock, which recitals and resolutions are as follows:

          WHEREAS, the Restated Certificate of Incorporation of this Corporation
     provides for a class of shares of preferred stock, par value $1.00 per
     share, issuable from time to time in one or more series; and

          WHEREAS, the Board of Directors of this Corporation is authorized to
     determine or alter the rights, preferences, privileges, and restrictions
     granted to or imposed upon any wholly unissued series of preferred stock,
     to fix the number of shares constituting any such series, and to determine
     the designation thereof, or any of them; and


 
     WHEREAS, in connection with the combination (the "Combination") of Baker 
International Corporation ("Baker") and Hughes Tool Company, pursuant to the 
Agreement and Plan of Reorganization, dated October 22, 1986, this Corporation 
assumed the obligations of Baker with respect to the convertible subordinated 
debentures of Baker issued under Baker's 1982 Convertible Debenture Plan as 
amended:

     WHEREAS, prior to the consummation of the Combination, the outstanding 
debentures were convertible into Series A through H Preferred Stock of Baker;

     WHEREAS, pursuant to the Combination, the outstanding debentures are now 
convertible into preferred stock of the same designated series of this 
Corporation;

     WHEREAS, the Board of Directors of this Corporation has previously 
authorized a series of One Hundred Thirty-six Thousand, Three Hundred 
Twenty-four (136,324) shares of Preferred Stock designated as Series I Preferred
Stock, no shares of which have been issued; and

     WHEREAS, the Board of Directors of this Corporation has previously 
authorized a series of One Hundred Seventy-five Thousand, Six Hundred Seven 
(175,607) shares of Preferred Stock designated as Series J Preferred Stock, of 
which Twenty-one Thousand, Four Hundred Seventy-two (21,472) shares have been 
issued; and

     WHEREAS, the Board of Directors of this Corporation desires, pursuant to 
its authority as aforesaid, to determine and fix the rights, preferences, 
privileges and restrictions relating to the eleventh series of preferred stock 
into which such debentures are convertible (such eleventh series hereinafter 
referred to as the "Series K Preferred Stock") and the number of shares 
constituting and the designation of such series;

     NOW THEREFORE, BE IT RESOLVED, that the Board of Directors hereby fixes and
determines there shall be a series of Preferred Stock designated Series K 
Preferred Stock; that the number of shares of such series shall be 

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One Hundred Seventy-seven Thousand, Eight Hundred Sixty-six (177,866); and that 
the preferences and relative, optional and other special rights of the
Series K Preferred Stock and the qualifications, limitations or restrictions of
such preferences and/or rights shall be as follows:

     1. DIVIDENDS. The holders of record of Preferred Stock shall be entitled to
receive, out of funds legally available therefor, cash dividends at the rate of 
$1.32 per share per fiscal year. All dividends payable hereunder shall be 
payable quarterly or otherwise as the Board of Directors may from time to time 
determine when and as declared by the Board of Directors. The right to such 
dividends on Preferred Stock shall not be cumulative and no right shall accrue 
to the holders of such shares by reason of the fact that dividends on such 
shares are not declared in any prior year. The holders of Preferred Stock shall 
be entitled to no other cash dividends in excess of the dividends at said rate.

     2. REDEMPTION. Any series of the Preferred Stock may be redeemed, in whole 
or in part, out of funds legally available therefor, at the option of the 
Corporation by vote of its Board of Directors, at any time or from time to time,
at the redemption price equal to $21.95 per share, plus an amount equal to all 
dividends declared but unpaid at the date fixed for redemption (such price, plus
such dividend, is hereafter referred to as the "redemption price").

     In case of the redemption of only a part of any series of the outstanding 
Preferred Stock, this Corporation shall designate by lot the shares to be 
redeemed or shall effect such redemption pro rata.

     Not more than 60 days, but at least 20 days prior to the date fixed for 
redemption, a written notice shall be mailed to each holder of record of
Series K Preferred Stock to be redeemed, by certified mail with postage prepaid,
addressed to each holder at his address as shown on the records of the
Corporation (a) notifying each holder of the election of the Corporation to
redeem such shares, (b) stating the date fixed for redemption thereof, (c)
setting forth the redemption price and (d) stating the place at which each
holder may obtain payment of the redemption price upon surrender of his share
certificates.

     On or after the date fixed in such notice of redemption, each holder of 
Series K Preferred Stock to be redeemed shall present and surrender his 
certificate or certificates representing such stock to this Corporation at a 
place designated in such notice and thereupon the redemption price of such 
shares shall be paid to or on 

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the order of the person whose name appears on such certificate or certificates 
as the owner thereof and each surrendered certificate shall be cancelled. In 
case less than all of the shares represented by any such certificate are 
redeemed, a new certificate shall be issued representing the unredeemed shares. 
From and after the date fixed in any such notice as the date of redemption, 
unless default is made in the payment of the redemption price, all rights of the
holders thereof as stockholders of the Corporation, except the right to receive 
the redemption price, shall cease, and such shares shall not thereafter be 
transferred on the books of the Corporation, and such stock shall not be deemed 
to be outstanding for any purpose whatsoever.

     The Corporation may at its option at any time after such notice of 
redemption has been given, deposit a sum sufficient to redeem, on the date fixed
for redemption shares of Series K Preferred Stock called for redemption, and not
yet redeemed with a bank or trust company in the United States, as a trust fund 
for the benefit of the respective holders of the shares designated for 
redemption, and such deposit, from and after the date fixed for redemption, 
shall constitute full payment of the redemption price of the shares to the 
holders thereof and shall be conclusive evidence that no default shall be made 
in the payment of the redemption price as to such shares.

     3. LIQUIDATION PREFERENCE. In the event of any voluntary or involuntary 
dissolution, liquidation or winding up of the Corporation, the holders of shares
of Series K Preferred Stock outstanding shall be entitled to receive, or to have
deposited in trust for them as provided in Section 2 hereof, out of assets of 
the Corporation, before any distribution of any asset shall be made to the 
holders of Common Stock or other shares junior to the Series K Preferred Stock 
as to distribution of assets, an amount which shall be equal to $21.95 per share
plus an amount equal to declared but unpaid dividends thereon. After the holders
of Series K Preferred Stock shall have received the foregoing amounts per share 
plus an amount equal to declared but unpaid dividends as aforesaid, they shall 
not participate in any remaining assets and surplus funds of the Corporation.

     If the amounts which each of the holders of the shares of the 
Series K Preferred Stock and any other series of preferred stock of the 
Corporation ranking equally as to distribution of assets with the shares of 
Series K Preferred Stock, are entitled to receive in such event are not paid, or
deposited in trust, in full, the shares of Series K Preferred Stock and of such 
other series shall share ratably in any distribution of assets in accordance 
with the amounts which would be payable on

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such distribution if all amounts to which the holders of the Series K Preferred 
Stock and of each such series are entitled were paid, or deposited in trust, in 
full.

     Neither the merger of the Corporation with or into any other corporation 
nor the sale of all or substantially all of its assets shall be deemed a 
dissolution, liquidation or winding up of the Corporation within the meaning of 
this Section.

     4. CONVERSION RIGHTS. The holders of shares of Series K Preferred Stock 
shall have conversion rights as follows:

     (a) The shares of Series K Preferred Stock shall be convertible, at the 
option of the respective holders thereof, at the office of the Corporation into 
fully paid and nonassessable shares (calculated to the nearest 1/100th of a 
share, fractions less than 1/100th of a share being disregarded) of Common Stock
of the Corporation, at the conversion price in effect at the time of conversion
determined as hereinafter provided, each share of the Series K Preferred Stock
being taken at $21.95 for the purposes of such conversion. The price at which
shares of Common Stock shall be deliverable upon conversion of shares of Series
K Preferred Stock of any series (herein called the "conversion price") shall be
initially $21.95 per share of Series K Preferred Stock, i.e., upon conversion,
each share of Series K Preferred Stock will be exchanged for one share of Common
Stock. Such initial conversion price shall be subject to adjustment from time to
time in certain instances, as hereinafter provided. The Corporation shall make
payment or adjustment on account of any dividends declared but not paid on
shares of Series K Preferred Stock surrendered for conversion. In case of the
call for redemption of any shares of Series K Preferred Stock, such right of
conversion shall terminate as to the shares designated for redemption, at the
close of business on the day preceding the day fixed for redemption, unless
default is made in the payment of the redemption price.

     (b) Before any holder of Series K Preferred Stock shall be entitled to 
convert the same into shares of Common Stock, he shall surrender the certificate
or certificates therefor, duly endorsed, at the office of the Corporation and 
shall give written notice to the Corporation that he elects to convert the same 
and shall state in writing therein the name or names in which he wishes the 
certificate or certificates for shares of Common Stock to be issued. If the 
holder fails to specify the name in which certificates are to be issued, they 
shall be issued in his name. The Corporation, as soon as practicable thereafter,
shall issue and deliver at such office to such holder of Series K Preferred 
Stock

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or to his nominee or nominees, certificates for the number of full shares of 
Common Stock to which he shall be entitled as aforesaid, together with cash in 
lieu of any fraction of a share as hereinafter provided. Such conversion shall 
be deemed to have been made as of the date of such surrender of the shares of 
Series K Preferred Stock to be converted (or, in the event of a proposed 
redemption and if the Corporation so allows, on the date of receipt of 
satisfactory notice of conversion if certificates of Series K Preferred Stock so
converted are thereafter delivered to the Corporation within 30 days), and the 
person or persons entitled to receive the shares of Common Stock issuable upon 
such conversion shall be treated for all purposes as the record holder or 
holders of such shares of Common Stock on said date.

     (c) The conversion price of Series K Preferred Stock shall be subject to 
adjustment, at any time or from time to time hereafter, if the Corporation shall
issue or sell any shares of Common Stock, under the circumstances set forth in 
subsections 4(d)(1) or 4(f) hereof, for a consideration per share less than the 
conversion price of Series K Preferred Stock in effect immediately prior to such
issue or sale ("Current Conversion Price"). In any such event, forthwith upon 
such issue or sale, the Current Conversion Price for Preferred Stock in effect 
immediately prior to such issue or sale shall be reduced to a price (calculated 
to the nearest cent) determined by dividing (i) an amount equal to the sum of 
(A) the number of shares of Common Stock outstanding immediately prior to such 
issue or sale multiplied by the then existing Current Conversion Price for 
Preferred Stock, and (B) the consideration, if any, received by the Corporation 
upon such issue or sale, by (ii) the total number of shares of Common Stock 
outstanding immediately after such issue or sale. No adjustment of the Current 
Conversion Price for Preferred Stock, however, shall be made in an amount less 
than $1.00 per share, but any lesser adjustment shall be carried forward and 
shall be made at the time of and together with the next subsequent adjustment 
which, together with any adjustments so carried forward, shall amount to $1.00 
per share or more.

     (d) For the purposes of such adjustments, the following provisions shall be
applicable:

          (1) In case at any time the Corporation shall declare a dividend or 
make any other distribution upon any stock of the Corporation payable in Common 
Stock, any Common Stock issuable in payment of such dividend or distribution 
shall be deemed to have been issued or sold without consideration.

          (2) In case at any time the Corporation shall take a record of the 
holders of Common Stock for 

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the purpose of entitling them to receive a dividend or other distribution 
payable in Common Stock, then such record date shall be deemed to be the date of
the issue or sale of the shares of Common Stock deemed to have been issued or 
sold upon the declaration of such dividend or the making of such other 
distribution or the date of the granting of such right of subscription or 
purchase, as the case may be.

          (3) The number of shares of Common Stock outstanding at any given time
shall include all shares of Common Stock issuable in respect of script 
certificates issued in lieu of fractions of common shares of Common Stock.

     (e) In case the Corporation shall, by dividend or otherwise, distribute to 
all holders of its Common Stock evidences of its indebtedness or assets 
(including securities, but excluding any rights or warrants to purchase Common 
Stock and any dividend of distribution paid in cash out of the retained earnings
of the Corporation, the Current Conversion Price shall be adjusted so that it 
shall equal the price determined by multiplying the Current Conversion Price in 
effect immediately prior to the close of business on the date fixed for the 
determination of stockholders entitled to receive such distribution by a 
fraction of which the numerator shall be the current market price per share (as 
determined by the Board of Directors of the Corporation) of the Common Stock on 
the date fixed for such determination less the then fair market value (as 
determined by the Board of Directors) of the portion of the assets or evidences 
of indebtedness so distributed applicable to one share of Common Stock and the 
denominator shall be such current market price per share of the Common Stock, 
such adjustment to become effective immediately prior to the opening of business
on the day following the date fixed for the determination of stockholders 
entitled to receive such distribution.

     (f) In case at any time the Corporation shall subdivide its outstanding 
shares of Common Stock into a greater number of shares, the Current Conversion 
Price in effect immediately prior to such subdivision shall be proportionately 
reduced and conversely, in case the outstanding shares of Common Stock of the 
Corporation, shall be combined into a smaller number of shares, the Current 
Conversion Price in effect immediately prior to such combination shall be 
proportionately increased.

     (g) Whenever the Current Conversion Price is adjusted, as herein provided, 
the Corporation shall promptly mail to each holder of Series K Preferred Stock 
notice of such adjustment, which notice shall set forth a brief statement of the
facts requiring such adjustment.

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     (h) In case of any capital reorganization or any reclassification of the 
capital stock of the Corporation or in case of the consolidation or merger of 
the Corporation with or into another corporation or the conveyance of all or 
substantially all of the assets of the Corporation to another corporation, each 
share of Series K Preferred Stock shall thereafter be convertible into the 
number of shares of stock or other securities or property to which a holder of 
the number of shares of Common Stock of the Corporation deliverable upon 
conversion of such shares of Series K Preferred Stock would have been entitled 
upon such reorganization, reclassification, consolidation, merger or conveyance;
and, in any such case, appropriate adjustment (as determined in good faith by 
the Board of Directors) shall be made in the application of the provisions 
herein set forth with respect to the rights and interests thereafter of the 
holders of the shares of Series K Preferred Stock, to the end that the 
provisions set forth herein shall thereafter be applicable, as nearly as 
reasonably may be, in relation to any shares of stock or other property 
thereafter deliverable upon the conversion of the shares of Series K Preferred 
Stock.

      (i) In case:

          (1) the Corporation shall take a record of the holders of shares of 
its Common Stock for the purpose of entitling them to receive a dividend, or any
other distribution, other than ordinary cash dividends; or

          (2) the Corporation shall take a record of the holders of shares of 
its Common Stock for the purpose of entitling them to subscribe for or purchase 
any shares of stock of any class or to receive any other rights; or

          (3) of any capital reorganization of the Corporation, 
reclassification of the capital stock of the Corporation (other than a 
subdivision or combination of its outstanding shares of Common Stock), 
consolidation or merger of the Corporation with or into another corporation, or 
conveyance of all or substantially all of the assets of the Corporation into 
another corporation; or

          (4) of the voluntary or involuntary dissolution, liquidation or
winding up of the Corporation, then the Corporation shall cause to be mailed to 
the holders of record of Series K Preferred Stock or any security convertible 
into Series K Preferred Stock at their last addresses as they shall appear on 
the records of the Corporation, at least 20 days (or 10 days in any case 
specified in clauses (1) and (2) above) prior

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to the applicable record date hereinafter specified, a notice stating (1) the 
date on which a record is to be taken for the purpose of such dividend or 
distribution of rights, or, if a record is not to be taken, the date as of which
the holders of Common Stock of record would be entitled to such dividend or 
distribution of rights, and (2) the date on which such capital reorganization, 
reclassification, consolidation, merger, sale, dissolution, liquidation or 
winding up is expected to become effective, and the date as of which it is 
expected that the holders of Common Stock of record shall be entitled to 
exchange their shares of Common Stock for securities or other assets deliverable
upon such reorganization, reclassification, consolidation, merger, sale, 
dissolution, liquidation or winding up.

     (j) The Corporation will at all times reserve and keep available out of its
authorized Common Stock and/or shares of its Common Stock then owned or held by 
or for the account of the Corporation, solely for the purpose of delivery upon 
conversion of Series K Preferred Stock such number of shares of Common Stock as 
shall then be deliverable upon the conversion of all outstanding or potentially 
issuable Series K Preferred Stock. All shares of Common Stock which shall be so 
deliverable shall be duly and validly issued and fully paid and nonassessable.

     (k) If any shares of Common Stock required to be reserved for purposes of 
conversion of Series K Preferred Stock require registration with or approval of 
any governmental authority under any federal or state law, or listing upon any 
national securities exchange, before such shares may be issued upon conversion, 
the Corporation will in good faith and as expeditiously as possible endeavor to 
cause such shares to be duly registered, approved or listed, as the case may be.

     (l) The Corporation shall pay any and all issue and other taxes that may be
payable in respect of any issue or delivery of shares of Common Stock on 
conversion of shares of Series K Preferred Stock pursuant hereto. The 
Corporation shall not, however, be required to pay any tax which may be payable 
in respect of any transfer involved in the issue and delivery of shares of 
Common Stock in a name other than that in which the shares of Series K Preferred
Stock so converted were registered, and no such issue or delivery shall be made 
unless and until the person requesting such issue has paid to the Corporation 
the amount of any such tax, or has established, to the satisfaction of the 
Corporation, that such tax has been paid.

     (m) No fractional shares of Common Stock shall be issued upon the 
conversion of shares of Series K

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Preferred Stock. If any fractional interest in a share of Common Stock would, 
except for the provisions of this subsection 4(m), be deliverable upon the 
conversion of any shares of Series K Preferred Stock, the Corporation shall, in 
lieu of delivering the fractional share therefor, adjust such fractional 
interest by payment to the holder of such surrendered shares of Series K 
Preferred Stock of an amount in cash equal (computed to the nearest cent) to the
current market value of such fractional interest, as determined in good faith by
the Board of Directors of the Corporation. This subsection shall similarly apply
to successive issues, sales, split-ups, combinations, reclassifications or 
reorganizations.

     5. VOTING RIGHTS. Except as provided by law or as provided above, the 
holders of Series K Preferred Stock shall not be entitled to notice of 
stockholders' meetings or to vote upon the election of directors or upon any 
other matter.

     RESOLVED FURTHER, that the Chairman of the Board, the President or any Vice
President, and the Secretary, the Chief Financial Officer, the Treasurer, or any
Assistant Secretary or Assistant Treasurer of this Corporation are each 
authorized to execute, verify and file a certificate of determination of 
preferences in accordance with Delaware law;

     IN WITNESS WHEREOF, said Baker Hughes Incorporated has caused this 
certificate to be signed by Thomas Cason, its Senior Vice President, and 
attested by Linda J. Smith, its Assistant Secretary, this 6th day of December, 
1989.

                                        
                                       BAKER HUGHES INCORPORATED


                                       By:          /s/ Thomas Cason
                                           -------------------------------------
                                           Thomas Cason
                                           Senior Vice President

ATTEST:

By:      /s/ Linda J. Smith
    -------------------------------
    Linda J. Smith
    Assistant Secretary

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