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                                                                     Exhibit 3.6

                            CERTIFICATE OF AMENDMENT
                                       OF
                          CERTIFICATE OF INCORPORATION
                                       OF
                            DURCO INTERNATIONAL INC.
                                     UNDER
                  SECTION 805 OF THE BUSINESS CORPORATION LAW


         Pursuant to the provisions of Section 805 of the Business Corporation
Law, the undersigned, William M. Jordan, President, and Ronald F. Shuff,
Secretary, of DURCO INTERNATIONAL INC., a New York corporation (the
"Corporation"), do hereby certify as follows:

         FIRST: The name of the corporation is Durco International Inc. The name
under which the corporation was formed was Duriron Castings Company.

         SECOND: The Certificate of Incorporation of the Corporation was filed
by the Department of State on May 1, 1912.

         THIRD: The amendments to the Certificate of Incorporation affected by
this Certificate are as follows:

                           Article FIRST of the Certificate of Incorporation is
                  hereby amended by deleting Article FIRST and by replacing such
                  article with the following:

                           "FIRST: The name of the corporation is Flowserve
                  Corporation."

                           Article THIRD of the Certificate of Incorporation is
                  hereby amended by deleting the first sentence of Article THIRD
                  and by replacing such deleted sentence with the following
                  sentence:

                           "THIRD: The aggregate number of shares which the
                  corporation shall have authority to issue is 121,000,000, of
                  which 1,000,000 shares, of the par value, of $1.00 each, shall
                  be Preferred Stock and 120,000,000 shares, of the par value of
                  $1.25 each, shall be Common Stock."


                  FOURTH: No change in the number of outstanding shares of
         Common Stock or Preferred Stock of the Corporation resulted from the
         above amendment to Article THIRD. However, as the result of such
         amendment, the total number of authorized shares of the Corporation is
         increased from 61,000,000 to 121,000,000 with the number of shares of
         Preferred Stock, of the par value of $1.00 each, being




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         unchanged from 1,000,000 shares and the number of shares of Common
         Stock, of the par value of $1.25 each, being increased from 60,000,000
         to 120,000,000 shares.

                  FIFTH, the foregoing amendment to the Certificate of
         Incorporation was authorized by the unanimous vote of the Directors
         present at a meeting of the Board of Directors duly convened and held
         on May 5, 1997, and such amendment was thereafter approved by an
         affirmative vote of a majority of all the outstanding shares of the
         Common Stock at a Special Meeting of Shareholders of the Corporation
         held on July 22, 1997.

                  IN WITNESS WHEREOF, we hereunto sign our respective names and
         affirm that the statements made herein are true under penalties of
         perjury, this 22nd day of July, 1997.



                                   /s/ William M. Jordan
                                   -----------------------------
                                   William M. Jordan,
                                   President


                                   /s/ Ronald F. Shuff
                                   -----------------------------
                                   Ronald F. Shuff
                                   Secretary