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                                                                     EXHIBIT 5.1



                                October 28, 2000



Flowserve Corporation
222 West Las Colinas Boulevard
Suite 1500
Irving, Texas  75039

Flowserve Finance B.V.
Parallelweg 6
Elten-Leur 4870 AA
The Netherlands



Ladies and Gentlemen:

                  We have acted as counsel to Flowserve Corporation, a New York
corporation (the "Company"), and its wholly owned subsidiary Flowserve Finance
B.V., a private company with limited liability organized under the laws of The
Netherlands ("FFBV"), in connection with the filing by the Company and FFBV
under the Securities Act of 1933, as amended, of a registration statement on
Form S-4 (the "Registration Statement") with the United States Securities and
Exchange Commission. Pursuant to the Registration Statement, up to
[X] 100,000,000 aggregate principal amount of FFBV's 12 1/4 % Senior
Subordinated Notes due 2010 (the "Outstanding Euro Notes") and $290,000,000
aggregate principal amount of the Company's outstanding 12 1/4 % Senior
Subordinated Notes due 2010 (the "Outstanding Dollar Notes" and, together with
the Outstanding Euro Notes, the "Outstanding Notes") are exchangeable for up to
a like principal amount of the Company's euro-denominated 12 1/4 % Senior
Subordinated Notes due 2010 (the "Euro Exchange Notes") and dollar-denominated
12 1/4 % Senior Subordinated Notes due 2010 (the "Dollar Exchange Notes",
together with the Euro Exchange Notes, the "Exchange Notes"). The Outstanding
Euro Notes were, and the Euro Exchange Notes will be, issued pursuant to an
Indenture dated as of August 8, 2000 relating to the Euro Notes (the "Euro Notes
Indenture") among FFBV, the Euro Note Guarantors, and The Bank of New York as
trustee, registrar, principal paying agent and transfer agent (the "Trustee").
The Outstanding Dollar Notes were, and the Dollar Exchange Notes will be, issued
pursuant to an Indenture dated as of August 8, 2000 relating to the Dollar Notes
(the "Dollar Notes Indenture" and, together with the Euro Notes Indenture, the
"Indentures") among the Company, the Dollar Note Guarantors and the Trustee. The
Exchange Notes and the Outstanding Notes are collectively referred to herein as
the "Notes."

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                  In this capacity, we have examined the Registration Statement,
the Indentures filed as Exhibits 4.7 and 4.8 to the Registration Statement, the
Outstanding Notes, forms of the Euro Exchange Note and the Dollar Exchange Note
contained in such Indentures and originals or copies certified or otherwise
identified to our satisfaction of such documents as we have deemed necessary or
appropriate to enable us to render the opinions expressed below.

                  The opinions stated herein are limited to the laws of the
State of New York, the General Corporation Law of the State of Delaware and the
federal laws of the United States, and we do not express any opinion herein
concerning any other laws.

                  Based upon the foregoing, it is our opinion:

                  (i) The Dollar Exchange Notes have been duly authorized and
               executed by the Company and, assuming that the Dollar Exchange
               Notes have been duly authorized and executed by each Dollar Note
               Guarantor under the laws of its jurisdiction of incorporation or
               formation, the Dollar Exchange Notes have been duly executed and
               delivered under the laws of the State of New York by each Dollar
               Note Guarantor and, assuming further that the Dollar Exchange
               Notes have been duly authenticated by the Trustee in accordance
               with the Dollar Notes Indenture, when the Dollar Exchange Notes
               have been exchanged for the Outstanding Dollar Notes as
               contemplated in the Registration Statement, the Dollar Exchange
               Notes will be duly authenticated and will constitute legal, valid
               and binding obligations of the Company and each Dollar Note
               Guarantor enforceable against the Company and each Dollar Note
               Guarantor in accordance with their terms.

                  (ii) The Euro Exchange Notes have been duly authorized and
               executed by the Company as guarantor and, assuming that the Euro
               Exchange Notes have been duly authorized and executed by FFBV
               under the laws of The Netherlands and by each Euro Note Guarantor
               (other than the Company) under the laws of its jurisdiction of
               incorporation, the Euro Exchange Notes have been duly executed
               and delivered under the laws of the State of New York by FFBV and
               each Euro Note Guarantor and, assuming further that the Euro
               Exchange Notes have been duly authenticated by the Trustee in
               accordance with the Euro Notes Indenture, when the Euro Exchange
               Notes have been exchanged for the Outstanding Euro Notes as
               contemplated in the Registration Statement, the Euro Exchange
               Notes will be duly authenticated and will constitute valid and
               binding obligations of FFBV, the Company and each other Euro Note
               Guarantor enforceable against FFBV, the Company and each other
               Euro Note Guarantor in accordance with their terms.

               Our opinions expressed above are subject to the following
qualifications:

               (a)  Our opinion as to the enforceability of the Notes is subject
                    to the effect of (i) any applicable bankruptcy, insolvency,
                    reorganization, moratorium or similar laws affecting
                    creditors' rights generally, (ii) general principles of
                    equity, including without limitation, concepts of
                    materiality, reasonableness, good faith and fair dealing
                    (regardless of whether considered in a proceeding in equity
                    or at law) and (iii) (solely with respect to obligations of
                    FFBV and Flowserve International Limited)

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                    possible judicial action giving effect to foreign
                    governmental actions or foreign laws affecting creditors'
                    rights; and

               (b)  We do not express any opinion as to the validity of any
                    consent or agreement to submit to the jurisdiction of any
                    United States federal court (other than personal
                    jurisdiction).

               We hereby consent to the use of this opinion as Exhibit 5.1
to the Registration Statement and to the use of our name under the caption
"Legal Matters" contained in the prospectus which is included in the
Registration Statement.


                                      Very truly yours,

                                      /s/ SHEARMAN & STERLING

CCP/CHL/JK/SAG