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                                                                     EXHIBIT 4.6




                        SECOND SUPPLEMENTAL INDENTURE
           


         SECOND SUPPLEMENTAL INDENTURE (this "Supplement"), dated and effective
as of December 6, 1996, is entered into by and among Energy Ventures, Inc., a
Delaware corporation (the "Company"), EVI Arrow, Inc., a Delaware corporation
and a wholly owned subsidiary of the Company ("EVI Arrow"), EVI Watson Packers,
Inc., a Delaware corporation and a wholly owned subsidiary of the Company ("EVI
Watson", together with EVI Arrow, the "New Guarantors"), and The Chase
Manhattan Bank (formerly known as Chemical Bank), a New York corporation, as
Trustee (the "Trustee").

                 RECITALS OF THE COMPANY AND THE NEW GUARANTORS

         WHEREAS, the Company, the Subsidiary Guarantors and the Trustee have
executed and delivered an Indenture dated as of March 15, 1994, among the
Company, the Subsidiary Guarantors and the Trustee (the "Original Indenture")
providing for the issuance by the Company of $120,000,000 aggregate principal
amount of the Company's 10 1/4% Senior Notes due 2004 (the "Securities") and
pursuant to which the Subsidiary Guarantors have agreed, jointly and severally,
to unconditionally guarantee the due and punctual payment of the principal of,
premium, if any, and interest on the Securities and all other amounts due and
payable under the Original Indenture and the Securities by the Company
("Indenture Obligations");

         WHEREAS, the Company, Prideco, Inc., a Texas corporation and a wholly
owned subsidiary of the Company ("Prideco"), and the Trustee executed a First
Supplemental Indenture, dated as of June 30, 1995, pursuant to which Prideco
became a Subsidiary Guarantor and agreed to unconditionally guarantee the
Indenture Obligations (the Original Indenture, as supplemented by the First
Supplemental Indenture, is hereinafter referred to as the "Indenture");

         WHEREAS, each of the New Guarantors has become a Material Restricted
Subsidiary and pursuant to Sections 12.3(b) and (d) is obligated to enter into
the Supplement thereby guaranteeing the punctual payment of all Indenture
Obligations as provided in Article XII of the Indenture;

         WHEREAS, pursuant to Section 8.1(f) of the Indenture, the Company, the
New Guarantors and the Trustee may enter into this Supplement without the
consent of any Holder;

         WHEREAS, the execution and delivery of this Supplement have been duly
authorized by a Board Resolution of the respective Board of Directors of the
Company and each of the New Guarantors; and

         WHEREAS, all conditions and requirements necessary to make the
Supplement valid and binding upon the Company and the New Guarantors, and
enforceable against the Company and the New Guarantors in accordance with its
terms, have been performed and fulfilled;

         NOW, THEREFORE, in consideration of the above premises, each of the
parties hereto agrees, for the benefit of the others and for the equal and
proportionate benefit of the Holders of the Securities, as follows:

                                  ARTICLE ONE
                               THE NEW GUARANTEE

         Section 101.  For value received, each of the New Guarantors, in
accordance with Article Twelve of the Indenture, hereby unconditionally
guarantees (the "New Guarantees"), jointly and severally among themselves and
the Subsidiary Guarantors, to the Trustee and the
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Holders, the due and punctual payment of the principal of, premium, if any, and
interest on the Securities and all other amounts due and payable under the
Indenture and the Securities by the Company, whether at maturity, by
acceleration, redemption, repurchase or otherwise as more specifically set
forth in Section 12.1 of the Indenture, including, without limitation, interest
on the overdue principal of, premium, if any, and interest on the Securities,
to the extent lawful, all in accordance with the terms of Article XII of the
Indenture and subject to the limitations set forth in Section 12.5 of the
Indenture.  Each of the agreements made and obligations assumed hereunder by
the New Guarantors shall constitute, and shall be deemed to constitute, a
Guarantee under the Indenture and for all purposes of the Indenture, and each
of the New Guarantors shall be considered a Subsidiary Guarantor for all
purposes of the Indenture as if it was originally named therein as a Subsidiary
Guarantor.

         Section 102.  The New Guarantees shall be automatically and
unconditionally released and discharged upon the occurrence of the events set
forth in Sections 3.1 and 12.4 of the Indenture.

                                  ARTICLE TWO
                                 MISCELLANEOUS

         Section 201.  Except as otherwise expressly provided or unless the
context otherwise requires, all terms used herein which are defined in the
Indenture shall have the meanings assigned to them in the Indenture.  Except as
supplemented hereby, the Indenture (including the Guarantees incorporated
therein) and the Securities are in all respects ratified and confirmed and all
the terms and provisions thereof shall remain in full force and effect.

         Section 202.  This Supplement shall be effective as of the date above
written.

         Section 203.  The recitals contained herein shall be taken as the
statements of the Company and the New Guarantors, and the Trustee assumes no
responsibility for the correctness.  The Trustee makes no representations as to
the validity or sufficiency of this Supplement.

         Section 204.  This Supplement shall be governed by and construed in
accordance with the laws of the jurisdiction which govern the Indenture and its
construction.

         Section 205.  This Supplement may be executed in any number of
counterparts each of which shall be an original, but such counterparts shall
together constitute but one and the same instrument.





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         IN WITNESS WHEREOF, the parties hereto have caused this Supplement to
be duly executed and their respective seals to be affixed hereunto and duly
attested all as of the day and year first above written.

                                        ENERGY VENTURES, INC.  
[Corporate Seal]

                                        By: /s/ JAMES G. KILEY    
                                            ------------------------------------
                                                James G. Kiley
                                                Vice President and
                                                Chief Financial Officer
Attest:


/s/ FRANCES R. POWELL           
------------------------------
    Frances R. Powell
    Assistant Secretary

                                        EVI ARROW, INC.
[Corporate Seal]

                                        By: /s/ JAMES G. KILEY               
                                            ------------------------------------
                                                James G. Kiley
                                                Vice President
Attest:


/s/ FRANCES R. POWELL           
------------------------------
    Frances R. Powell
    Assistant Secretary


                                        EVI WATSON PACKERS, INC.
[Corporate Seal]

                                        By: /s/ JAMES G. KILEY                
                                            ------------------------------------
                                                James G. Kiley
                                                Vice President
Attest:


/s/ FRANCES R. POWELL           
------------------------------
    Frances R. Powell
    Assistant Secretary


                                        THE CHASE MANHATTAN BANK
[Corporate Seal]

                                        By:    /s/ W B. DODGE          
                                               ---------------------------------
                                        Name:      W.B. DODGE              
                                               ---------------------------------
                                        Title:     VICE PRESIDENT 
                                               ---------------------------------
Attest:


                                         
------------------------------
    Assistant Secretary





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