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                                                                     Exhibit 3.1

                    RESTATED CERTIFICATE OF INCORPORATION 
                                      OF 
                          BAKER HUGHES INCORPORATED 
                                        
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                   PURSUANT TO SECTIONS 245 AND 242 OF THE 
               GENERAL CORPORATION LAW OF THE STATE OF DELAWARE
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  BAKER HUGHES INCORPORATED (the "Corporation"), a corporation organized and 
existing under and by virtue of the General Corporation Law of the State of
Delaware, hereby adopts the following Restated Certificate of Incorporation
pursuant to Sections 245 and 242 of said General Corporation Law and certifies
as follows:

    1. The name of this corporation is: 

      BAKER HUGHES INCORPORATED. 
                                          
    2. The Certificate of Incorporation of the Corporation was originally filed
  with the Secretary of State of the State of Delaware on November 3, 1986. 
                                          
    3. The Restated Certificate of Incorporation was duly adopted by unanimous
  written consent of the Board of Directors of the Corporation dated December
  17, 1986, and by unanimous vote of all the stockholders on December 18, 1986
  in accordance with the provisions of Sections 242 and 245 of the General
  Corporation Law of the State of Delaware.

    4. The Restated Certificate of Incorporation supersedes the original 
  Certificate of Incorporation.

    5. The Certificate of Incorporation is hereby amended and restated in its
  entirety to read as follows: 

      FIRST: The name of this Corporation is:

        BAKER HUGHES INCORPORATED 

      SECOND: The address of its registered office in the State of Delaware is
    The Corporation Trust Center, 1209 Orange Street in the City of Wilmington,
    County of New Castle. The name of its registered agent at such address is
    The Corporation Trust Company.

      THIRD: The nature of the business or purposes to be conducted or
    promoted is to engage in any lawful act or activity for which corporations 
    may be organized under the General Corporation Law of Delaware. 

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      FOURTH: The total number of shares of stock which the Corporation shall
    have the authority to issue is 415,000,000 shares of capital stock
    consisting of 15,000,000 shares of preferred stock, par value $1.00 per 
    share (the "Preferred Stock") and 400,000,000 shares of common stock, par 
    value $l.00 per share (the "Common Stock"). 
                                          
      The designations, powers, preferences and relative, participating,
    optional or other special rights and qualifications, limitations or 
    restrictions of the Preferred Stock shall be established by resolution of
    the Board of Directors pursuant to Section 151 of the General Corporation
    Law of the State of Delaware. 
                                          
      FIFTH: In furtherance and not in limitation of the powers conferred by
    statute, the Board of Directors is expressly authorized to make, alter or
    repeal the by-laws of the Corporation. 
                                          
      SIXTH: Election of directors need not be by written ballot unless the
    by-laws of the Corporation shall so provide. 
                                     
      SEVENTH: The by-laws of the Corporation shall not be made, repealed,
    altered, amended or rescinded by the stockholders of the Corporation except
    by the vote of the holders of not less than 75% of the total voting power
    of all shares of stock of the Corporation entitled to vote in the election
    of directors, considered for purposes of this Article SEVENTH as one class. 
                                          
      EIGHTH: No action shall be taken by the stockholders except at an annual
    or special meeting of stockholders and stockholders may not act by written
    consent.

      NINTH: Special meetings of the stockholders of the Corporation for any
    purpose or purposes may be called at any time by the Board of Directors, or
    by a committee of the Board of Directors which has been duly designated by
    the Board of Directors and whose powers and authority, as provided in a
    resolution of the Board of Directors or in the by-laws of the Corporation,
    include the power to call such meetings. Special meetings of stockholders
    of the Corporation may not be called by any other person or persons. 
                                          
      TENTH: No director of this Corporation shall be personally liable to the
    Corporation or its stockholders for monetary damages for breach of
    fiduciary duty as a director, except for liability (i) for any breach of 
    the director's duty of loyalty to the Corporation or its stockholders, (ii) 
    for acts or omissions not in good faith or which involve intentional
    misconduct or a knowing violation of the law, (iii) under Section 174 of
    the General Corporation Law of Delaware, or (iv) for any transaction from
    which the director derived an improper personal benefit. 

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      If the General Corporation Law of the State of Delaware is hereafter
    amended to authorize corporate action further limiting or eliminating the
    personal liability of directors, then the liability of the director to the
    Corporation shall be limited or eliminated to the full extent permitted by
    the General Corporation Law of the State of Delaware, as so amended from
    time to time. Any repeal or modification of this Article shall be
    prospective only, and shall not adversely affect any limitation on the
    personal liability of a director of the Corporation existing at the time of
    such repeal or modification. 
                                          
      ELEVENTH: The initial directors of the Corporation shall serve for a
    term ending on the date of the first annual meeting of stockholders next
    following September 30, 1987. Thereafter, the Board of Directors shall be
    divided into three classes, Class I, Class II and Class III. The number of
    directors in each class shall be the whole number contained in the quotient
    arrived at by dividing the authorized number of directors by three, and if
    a fraction is also contained in such quotient then if such fraction is 
    one-third (1/3) the extra director shall be a member of Class III and if
    the fraction is two-thirds (2/3) one of the extra directors shall be a
    member of Class III and the other shall be a member of Class II. After
    division of the Board of Directors into classes, each director shall serve
    for a term ending on the date of the third annual meeting following the
    annual meeting at which such director was elected; provided, however, that
    the initial directors appointed to Class I shall serve for a term ending on
    the date of the first annual meeting next following September 30, 1988, the
    initial directors appointed to Class II shall serve for a term ending on
    the date of the second annual meeting next following September 30, 1988,
    and the initial directors appointed to Class III shall serve for a term 
    ending on the date of the third annual meeting next following September 30, 
    1988. 
                                          
      The number of directors shall be fixed from time to time by the by-laws
    of the Corporation or an amendment thereof duly adopted by the Board of
    Directors or by the stockholders acting in accordance with Article SEVENTH
    herein. In the event of any increase or decrease in the authorized number
    of directors, (a) each director then serving as such shall nevertheless
    continue as a director of the class of which he is a member until the
    expiration of his current term, or his prior death, retirement, resignation
    or removal, and (b) the newly created or eliminated directorships
    resulting from such increase or decrease shall be apportioned by the Board
    of Directors to such class or classes as shall, so far as possible, bring
    the number of directors in the respective classes into conformity with the
    formula in this Article, as applied to the new authorized number of
    directors.

      Notwithstanding any of the foregoing provisions of this Article, each
    director shall serve until his successor is elected and qualified or until 
    his death, retirement, resignation or removal. No director may be removed 
    during his term except for cause. 


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      TWELFTH: The affirmative vote of the holders of not less than 75% of 
    the outstanding shares of "Voting Stock" (as hereinafter defined) of the 
    Corporation, including the affirmative vote of the holders of not less than 
    66 2/3% of the outstanding shares of Voting Stock not owned, directly or 
    indirectly, by any "Related Person" (as hereinafter defined), shall be 
    required for the approval or authorization of any "Business Combination" 
    (as hereinafter defined) of the Corporation with any Related Person; 
    provided, however, that the 66 2/3% voting requirement referred to above 
    shall not be applicable if the Business Combination is approved by the
    affirmative vote of the holders of not less than 90% of the outstanding 
    shares of Voting Stock; and further provided that the 75% voting
    requirement shall not be applicable if: 
                                          
    (1) The Board of Directors of the Corporation by a vote of not less than 75%
  of the directors then holding office (a) have expressly approved in advance
  the acquisition of outstanding shares of Voting Stock of the Corporation that
  caused the Related Person to become a Related Person or (b) have approved the
  Business Combination prior to the Related Person involved in the Business
  Combination having become a Related Person; 
                                          
    (2) The Business Combination is solely between the Corporation and another
  corporation, 100% of the Voting Stock of which is owned directly or
  indirectly by the Corporation; or 
                                          
    (3) All of the following conditions have been met: (a) the Business 
  Combination is a merger or consolidation, the consummation of which is
  proposed to take place within one year of the date of the transaction pursuant
  to which such person became a Related Person and the cash or fair market value
  of the property, securities or other consideration to be received per share by
  holders of Common Stock of the Corporation in the Business Combination is not
  less than the highest per share price (with appropriate adjustments for
  recapitalizations and for stock splits, reverse stock splits and stock
  dividends) paid by the Related Person in acquiring any of its holdings of the
  Corporation's Common Stock; (b) the consideration to be received by such
  holders is either cash or, if the Related Person shall have acquired the
  majority of its holdings of the Corporation's Common Stock for a form of
  consideration other than cash, in the same form of consideration as the
  Related Person acquired such majority; (c) after such Related Person has
  become a Related Person and prior to the consummation of such Business
  Combination: (i) except as approved by a majority of the "Continuing 
  Directors" (as hereinafter defined), there shall have been no failure to
  declare and pay at the regular date therefor any full quarterly dividends
  (whether or not cumulative) on any outstanding Shares of Preferred Stock of
  the Corporation, (ii) there shall have been no reduction in the annual rate
  of dividends paid per share on the Corporation's Common Stock (adjusted as
  appropriate for recapitalizations and for stock splits, reverse stock splits
  and stock dividends) except as approved by a majority of the Continuing


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  Directors, (iii) such Related Person shall not have become the "Beneficial
  Owner" (as hereinafter defined) of any additional shares of Voting Stock of
  the Corporation except as part of the transaction which resulted in such
  Related Person becoming a Related Person, and (iv) such Related Person shall
  not have received the benefit, directly or indirectly (except proportionately
  as a stockholder), of any loans, advances, guarantees, pledges or other
  financial assistance or any tax credits or other tax advantages provided by
  the Corporation, whether in anticipation of or in connection with such
  Business Combination or otherwise; and (d) a proxy statement, responsive to
  the requirements of the Securities Exchange Act of 1934, as amended ("Exchange
  Act") and the rules and regulations thereunder (or any subsequent provisions
  replacing the Exchange Act, rules or regulations), shall be mailed to all
  stockholders of record at least 30 days prior to the consummation of the
  Business Combination for the purpose of soliciting stockholder approval of the
  Business Combination and shall contain at the front thereof, in a prominent
  place, any recommendations as to the advisability (or inadvisability) of the
  Business Combination which the Continuing Directors, or any of them, may
  choose to state and, if deemed advisable by a majority of the Continuing
  Directors, an opinion of a reputable investment banking firm as to the
  fairness (or unfairness) of the terms of such Business Combination from the
  point of view of the remaining stockholders of the Corporation (such
  investment banking firm to be selected by a majority of the Continuing
  Directors and to be paid a reasonable fee for its services by the Corporation
  upon receipt of such opinion).
                                          
  For the purposes of this Article: 
                                          
    (i) The term "Business Combination" shall mean (a) any merger or 
  consolidation of the Corporation or a subsidiary with or into a Related
  Person, (b) any sale, lease, exchange, transfer or other disposition,
  including without limitation a mortgage or any other security device, of all
  or any "Substantial Part" (as hereinafter defined) of the assets either of the
  Corporation (including, without limitation, any voting securities of a
  subsidiary) or of a subsidiary to a Related Person (other than a distribution
  by the Corporation or a subsidiary to the Related Person of assets in
  connection with a pro rata distribution by the Corporation to all
  stockholders), (c) any merger or consolidation of a Related Person with or
  into the Corporation or a subsidiary of the Corporation, (d) any sale, lease,
  exchange, transfer or other disposition of all or any Substantial Part of the
  assets of a Related Person to the Corporation or a subsidiary of the
  Corporation, (e) the issuance of any securities (other than by way of pro rata
  distribution to all stockholders) of the Corporation or a subsidiary of the
  Corporation to a Related Person, (f) the acquisition by the Corporation or a
  subsidiary of the Corporation of any securities of a Related Person, (g) any
  recapitalization that would have the effect of increasing the voting power of
  a Related Person, (h) any series or combination of transactions having the
  

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  same effect, directly or indirectly, as any of the foregoing and (i) any
  agreement, contract or arrangement providing for any of the transactions
  described in this definition of Business Combination. 
                                          
    (ii) The term "Continuing Director" shall mean any member of the Board of
  Directors of the Corporation who is not affiliated with a Related Person and
  who was a member of the Board of Directors immediately prior to the time that
  the Related Person became a Related Person, and any successor to a Continuing
  Director who is not affiliated with the Related Person and is recommended to
  succeed a Continuing Director by a majority of Continuing Directors then
  serving as members of the Board of Directors of the Corporation. 
                                          
    (iii) The term "Related Person" shall mean and include any individual,
  corporation, partnership or other person or entity which, together with its
  "Affiliates" and "Associates" (as defined on October 1, 1986 in Rule 12b-2
  under the Exchange Act), is the "Beneficial Owner" (as defined on October 1,
  1986 in Rule 13d-3 under the Exchange Act) in the aggregate of 10% or more of
  the outstanding Voting Stock of the Corporation, and any Affiliate or
  Associate of any such individual, corporation, partnership or other person or
  entity. 
                                          
    (iv) The term "Substantial Part" shall mean more than 10% of the book value
  of the total assets of the Corporation in question as of the end of its most
  recent fiscal year ending prior to the time the determination is being made. 
                                          
    (v) Without limitation, any shares of Common Stock of the Corporation that
  any person has the right to acquire pursuant to any agreement, or upon
  exercise of conversion rights, warrants or options, or otherwise, shall be
  deemed beneficially owned by such person. 
                                          
    (vi) For the purposes of subparagraph (3) of this Article, the term "other
  consideration to be received" shall include, without limitation, Common Stock
  of the Corporation retained by its existing public shareholders in the event
  of a Business Combination in which the Corporation is the surviving
  corporation. 
                                          
    (vii) The term "Voting Stock" shall mean all outstanding shares of capital
  stock of the Corporation or another corporation entitled to vote generally in
  the election of directors and each reference to a proportion of shares of
  Voting Stock shall refer to such proportion of the votes entitled to be cast
  by such shares. 
                                          
    THIRTEENTH: The provisions set forth in this Article THIRTEENTH and in
  Articles SEVENTH (dealing with the alteration of Bylaws by stockholders),
  EIGHTH (dealing with the prohibition against stockholder action without
  meetings), TENTH (dealing with 


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  liability of directors), ELEVENTH (dealing with the classification and number
  of directors) and TWELFTH (dealing with the 75% vote of stockholders required
  for certain Business Combinations) herein may not be repealed or amended in
  any respect, and no Article imposing cumulative voting in the election of
  directors may be added, unless such action is approved by the affirmative vote
  of not less than 75% of the total voting power of all shares of stock of the
  Corporation entitled to vote in the election of directors, considered for
  purposes of this Article THIRTEENTH as one class. Amendment to the provisions
  set forth in this Article THIRTEENTH and in Article TWELFTH shall also require
  the affirmative vote of 66 2/3% of such total voting power excluding the vote
  of shares owned by a "Related Person" (as defined in Article THIRTEENTH). The
  voting requirements contained in Article SEVENTH, Article TWELFTH and this
  Article THIRTEENTH herein shall be in addition to the voting requirements
  imposed by law, other provisions of this Certificate of Incorporation or any
  Certificate of Designation of Preferences in favor of certain classes or
  series of classes of shares of the Corporation.
                                          
    FOURTEENTH: The Corporation reserves the right to amend, alter, change or
  repeal any provisions contained in this Restated Certificate of 
  Incorporation, in the manner now or hereafter prescribed by statute, and all 
  rights conferred upon stockholders herein are granted subject to this 
  reservation. Notwithstanding the foregoing, the provision set forth in 
  Articles SEVENTH, EIGHTH, TENTH, ELEVENTH, TWELFTH and THIRTEENTH may not be
  repealed or amended in any respect unless such repeal or amendment is 
  approved as specified in Article THIRTEENTH herein. 
                                          
  IN WITNESS WHEREOF, BAKER HUGHES INCORPORATED has caused this Restated
Certificate of Incorporation to be executed, signed and acknowledged by Patrick
T. Doyle, its Vice President, who states under penalty of perjury that the
facts stated herein are true, and to be attested by Sandra E. Alford, its
Assistant Secretary this 3rd day of April, 1987. 


                                            /s/ Patrick T. Doyle
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                                              Patrick T. Doyle
                                               Vice President

Attest:

    /s/ Sandra E. Alford
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      Sandra E. Alford 
     Assistant Secretary


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