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                                                                   Exhibit 10.15

                          EIGHTH AMENDATORY AGREEMENT


                 EIGHTH AMENDATORY AGREEMENT ("Amendment No. 8"), dated as of
September 13, 1995, among EVI-HIGHLAND PUMP COMPANY, a Delaware corporation
("Highland"), GRANT PRIDECO, INC., a Delaware corporation formerly known as
Grant TFW Inc. ("Grant"), MALLARD BAY DRILLING, INC., a Louisiana corporation
("Mallard") (Highland, Grant and Mallard being hereinafter sometimes
collectively referred to as the "Borrowers"), ENERGY VENTURES, INC., a Delaware
corporation (the "Guarantor"), and TRANSAMERICA BUSINESS CREDIT CORPORATION, a
Delaware corporation (the "Lender"), to the Amended and Restated Loan and
Security Agreement referred to below.

                 WHEREAS, the Borrowers, the Guarantor and the Lender are
parties to an Amended and Restated Loan and Security Agreement dated October
13, 1992 (the "Original Loan Agreement"); and

                 WHEREAS the Borrowers, the Guarantor and the Lender have
amended the Original Loan Agreement pursuant to (i) a Letter Agreement dated
March 12, 1993 (the "Letter Agreement Amendment"), (ii) a First Amendatory
Agreement dated as of May 5, 1993 ("Amendment No. 1"), (iii) a Second
Amendatory Agreement dated as of August 12, 1993 ("Amendment No. 2"), (iv) a
Third Amendatory Agreement dated as of October 12, 1993 ("Amendment No. 3"),
(v) a Fourth Amendatory Agreement dated as of February  21, 1994 ("Amendment
No. 4"), (vi) a Fifth Amendatory Agreement dated as of March 22, 1994
("Amendment No. 5"), (vii) a Sixth Amendatory Agreement dated as of June 30,
1994 ("Amendment No. 6"), and a Seventh Amendatory Agreement dated as of May
18, 1995 ("Amendment No. 7"; the Original Loan Agreement as amended by the
Letter Agreement Amendment and Amendments No. 1, No. 2, No. 3, No. 4, No. 5 ,
No. 6 and No. 7 being hereinafter referred to as the "Loan Agreement"); and

                 WHEREAS, rather than preparing a new loan agreement, the
Borrowers, the Guarantor and the Lender now desire to further amend and modify
the Loan Agreement;

                 NOW, THEREFORE, in consideration of the mutual covenants
herein contained and for good and other valuable consideration, the receipt and
adequacy of which are hereby acknowledged, the parties hereto agree as follows:

                 1.       Capitalized terms used but not defined in this
Amendment No. 8 shall have the meanings given to those terms in the Loan
Agreement.

                 2.       Subject to the satisfaction of the conditions set
forth in Paragraph 9 of this Amendment No. 8, the following definitions shall
be added to Article 1 of the Loan Agreement in appropriate alphabetical order:

                          "Eighth Amendment Date" shall mean September 13,
1995.
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                          "Exchange Notes" shall mean the 10 1/4% Exchange
                 Notes due 2004, issued or to be issued by the Guarantor
                 pursuant to the Indenture, in the aggregate original principal
                 amount, together with the aggregate principal amount of the
                 Senior Notes, of $120,000,000.

                          "Indenture" shall mean the Indenture dated as of
                 March 15, 1994, among the Guarantor, as issuer, certain
                 Subsidiaries of the Guarantor, as guarantors, and Chemical
                 Bank, as trustee, pursuant to which the Senior Notes and the
                 Exchange Notes have been or will be issued.

                          "Prideco" shall mean Prideco, Inc., a Texas
                 corporation which is a wholly-owned subsidiary of the
                 Guarantor and the parent of Grant.

                          "Prideco Guaranty" shall mean the Prideco Guaranty,
                 dated June 30, 1995, executed by Prideco in favor of the
                 Lender.

                          "Senior Notes" shall mean the 10 1/4% Senior Notes
                 due 2004, issued or to be issued by the Guarantor pursuant to
                 the Indenture, in the aggregate original principal amount,
                 together with the aggregate principal amount of the Exchange
                 Notes, of $120,000,000.

                 3.       Subject to the satisfaction of the conditions set
forth in Paragraph 9 of this Amendment No. 8, the definition of the term
"Maximum Amount of the Facility" set forth in Article 1 of the Loan Agreement
is amended in its entirety to read as follows:

                          "Maximum Amount of the Facility" shall mean

                          (a) as of any date on and after the Original Closing
                 Date to but excluding the Second Amendment Date, Thirty-Four
                 Million Dollars ($34,000,000),

                          (b) as of any date on and after the Second Amendment
                 Date to but excluding the Eighth Amendment Date, Fifty Million
                 Dollars ($50,000,000), and

                          (c) as of any date on and after the Eighth Amendment
Date, Sixty Million Dollars ($60,000,000).

                 4.       Subject to the satisfaction of the conditions set
forth in Paragraph 9 of this Amendment No. 8, the reference to "Twelve Million
Dollars ($12,000,000)" set forth in clause (ii) of the first proviso of
Subsection (a) of Section 2.01 of the Loan Agreement is hereby amended to read
"Nineteen Million Dollars ($19,000,000)".

                 5.       Subject to the satisfaction of the conditions set
forth in Paragraph 9 of this Amendment No. 8, Section 2.06 of the Loan
Agreement is hereby deleted in its entirety.





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                 6.       Subject to the satisfaction of the conditions set
forth in Paragraph 9 of this Amendment No. 8, Article 4 of the Loan Agreement
is hereby amended to read in its entirety as follows:

                          4.      Early Termination.  The Borrowers shall have
                 the right to terminate this Agreement, effective as of any
                 date prior to the regularly scheduled termination date that is
                 then in effect pursuant to the first sentence of Article 20 of
                 this Agreement, on sixty (60) days' prior written notice to
                 the Lender, provided, that on the date of such early
                 termination (A) all Obligations, including all interest and
                 fees payable on the date of such termination, shall be paid in
                 full and (B) any notice of termination pursuant to this
                 Article 4 is accompanied by an early termination premium in an
                 amount equal to one percent (1%) of the Maximum Amount of the
                 Facility; provided, however, that no such early termination
                 premium shall be due if the full amount of the funds for such
                 prepayment are provided by an Affiliate of the Lender.

                 7.       Subject to the satisfaction of the conditions set
forth in Paragraph 9 of this Amendment No. 8, the first sentence of Article 20
of the Loan Agreement is hereby amended in its entirety to read as follows:

                 The term of this Agreement shall be for a period of four (4)
                 years commencing on the Second Amendment Date, unless sooner
                 terminated according to its terms, and it shall thereafter
                 continue from year to year unless terminated by either the
                 Borrowers or the Lender by giving the other party sixty (60)
                 days' prior written notice before the commencement of the next
                 contract year.

                 8.       The Borrowers and the Guarantor hereby represent and
warrant to the Lender that (a) the execution, delivery and performance of this
Amendment No. 8 and the other documents and instruments to be executed and
delivered in connection herewith by the Borrowers, the Guarantor and Prideco
are within their respective corporate powers and have been (or, prior to the
execution and delivery thereof, will have been) duly authorized by all
necessary corporate action; (b) no consent of the holders of any of the Notes,
the Senior Notes or the Exchange Notes is required in connection with the
execution, delivery and performance of this Amendment No. 8, the other
documents and instruments to be executed and delivered in connection herewith
by the Borrowers, the Guarantor and Prideco, and the Loan Agreement as amended
hereby; (c) no consent, approval, authorization of, or declaration or filing
with, any governmental or public authority, and no consent of any other Person,
is required in connection with the execution, delivery and performance of this
Amendment No. 8, the other documents and instruments to be executed and
delivered in connection herewith by the Borrowers, the Guarantor and Prideco,
and the Loan Agreement as amended hereby, except for such consents, approvals,
authorizations, declarations and filings the failure to obtain any of which
would not materially and adversely affect the business, condition (financial or
otherwise), results of operations or properties of the Guarantor and its
Subsidiaries, taken as a whole, and those others already obtained; (d) this
Amendment No. 8 has been duly executed by the Borrowers and the Guarantor; (e)
this





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Amendment No. 8 and the Loan Agreement as amended hereby constitute the legal,
valid and binding obligation of the Borrowers and the Guarantor, enforceable
against them in accordance with their respective terms; (f) the execution,
delivery and performance by the Borrowers, the Guarantor and Prideco of this
Amendment No. 8, the other documents and instruments to be executed and
delivered in connection herewith by the Borrowers, the Guarantor and Prideco,
and the Loan Agreement as amended hereby do not and will not conflict with, or
constitute a violation or breach of, or constitute a default under, or result
in the creation or imposition of any lien upon the property of the Borrowers,
the Guarantor or Prideco by reason of the terms of (1) the Note Purchase
Agreement or the Indenture; (2) any other contract, mortgage, lien, lease,
agreement, indenture or instrument to which the Borrowers, the Guarantor or
Prideco is a party or which is binding upon it, except for such breach or
default as would not materially and adversely affect the business, condition
(financial or otherwise), results of operations or properties of the Guarantor
and its Subsidiaries, taken as a whole; (3) any requirement of law applicable
to the Borrowers, the Guarantor or Prideco; or (4) the Certificate or Articles
of Incorporation or By-Laws of the Borrowers, the Guarantor or Prideco; (g)
each of the representations and warranties made by the Borrowers in the Loan
Agreement and the other Loan Documents are true and correct in all material
respects as of the date hereof (except to the extent that any of those
representations and warranties are expressly limited to an earlier date); and
(h) no event has occurred and is continuing which constitutes a Default or an
Event of Default.

                 9.       This Amendment No. 8, and the amendments provided for
herein, shall be effective as of the date first above written upon the
satisfaction of the following conditions precedent:

                 (a)      The Lender shall have received a copy of this
         Amendment No. 8 duly executed by the Borrowers and the Guarantor;

                 (b)      Prideco shall have executed and delivered to the
         Lender the Confirmation of Loan Documents set forth below;

                 (c)      The representations and warranties contained herein,
         in the Loan Agreement and in all other Loan Documents shall be true
         and correct in all material respects both as of the date hereof and
         immediately after giving effect to this Amendment (except to the
         extent that any of those representations and warranties are expressly
         limited to an earlier date);

                 (d)      No Default or Event of Default shall have occurred
         and be existing either before or immediately after giving effect to
         this Amendment No. 8;

                 (e)      The Lender shall have received a copy of the
         resolutions (in form and substance reasonably satisfactory to the
         Lender) of the Board of Directors of each of the Borrowers, the
         Guarantor and Prideco authorizing (i) the execution, delivery and
         performance of this Amendment No. 8, the documents referred to herein,
         and the other Loan Documents contemplated hereby and thereby, and the
         Loan Agreement as amended hereby, and (ii) the consummation





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         of the transactions contemplated hereby and thereby (including,
         without limitation, the extension of the term of the Loan Agreement,
         the increase in the Maximum Amount of the Facility and the increase in
         Grant's Inventory sublimit), all certified by the Secretary or an
         Assistant Secretary of each Borrower, the Guarantor and Prideco on the
         date hereof.  Each such certificate shall state that the resolutions
         set forth therein have not been amended, modified, revoked or
         rescinded as of the date of such certificate; and

                 (f)      The Lender shall have received an opinion of Messrs.
         Fulbright & Jaworski, counsel to the Borrowers, the Guarantor and
         Prideco, in form and substance satisfactory to the Lender, with
         respect to the execution, delivery and enforceability of this
         Amendment No. 8 and the Loan Agreement as amended hereby, and covering
         such other matters related thereto as the Lender shall reasonably
         require.

                 10.      Except as expressly modified and amended hereby, the
Loan Agreement is ratified and confirmed in all respects.

                 11.      THIS AMENDMENT NO. 8 SHALL BE GOVERNED BY, AND
CONSTRUED AND INTERPRETED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW
YORK.

                 12.      This Amendment No. 8 may be executed in any number of
counterparts and by different parties hereto on separate counterparts, each of
which counterparts, when so executed and delivered, shall be deemed to be an
original and all of which counterparts, taken together, shall constitute but
one and the same Amendment No. 8.

                 13.      This Amendment No. 8 constitutes a modification and
amendment of the existing Loan Agreement and is not a new loan agreement.





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                 IN WITNESS WHEREOF, each of the parties hereto has caused this
Amendment No. 8 to be executed by their officers thereunto duly authorized as
of the date first above written.


                                   EVI-HIGHLAND PUMP COMPANY                  
                                                                              
                                   By:  /s/ John C. Coble                     
                                      -------------------------------         
                                      Name:  John C. Coble                    
                                      Title:  Executive Vice President        
                                                                              
                                                                              
                                   GRANT PRIDECO, INC.                        
                                                                              
                                   By:  /s/ John C. Coble                     
                                      -------------------------------         
                                      Name:  John C. Coble                    
                                      Title:  Executive Vice President        
                                                                              
                                                                              
                                   MALLARD BAY DRILLING, INC.                 
                                                                              
                                   By:  /s/ John C. Coble                     
                                      -------------------------------         
                                      Name:  John C. Coble                    
                                      Title:  Executive Vice President        
                                                                              
                                                                              
                                   ENERGY VENTURES, INC.                      
                                                                              
                                   By:  /s/ John C. Coble                     
                                      -------------------------------         
                                      Name:  John C. Coble                    
                                      Title:  Executive Vice President        
                                                                              
                                                                              
                                   TRANSAMERICA BUSINESS CREDIT               
                                            CORPORATION                       
                                                                              
                                   By:  /s/ Sara V. Traberman                 
                                      -------------------------------         
                                      Name:  Sara V. Traberman                
                                      Title:  Vice President                  
                                                                              





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