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                                                                    EXHIBIT 31.2

                                CERTIFICATION OF
                            CHIEF FINANCIAL OFFICER

I, J. Ronald Hansen, certify that:

     1. I have reviewed this annual report on Form 10-K for the fiscal year
        ended March 31, 2004 of Graham Corporation;

     2. Based on my knowledge, this report does not contain any untrue statement
        of a material fact or omit to state a material fact necessary to make
        the statements made, in light of the circumstances under which such
        statements were made, not misleading with respect to the period covered
        by this report;

     3. Based on my knowledge, the financial statements, and other financial
        information included in this report, fairly present in all material
        respects the financial condition, results of operations and cash flows
        of the registrant as of, and for, the periods presented in this report;

     4. The registrant's other certifying officer(s) and I are responsible for
        establishing and maintaining disclosure controls and procedures (as
        defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the
        registrant and have:

          (a) Designed such disclosure controls and procedures, or caused such
              disclosure controls and procedures to be designed under our
              supervision, to ensure that material information relating to the
              registrant, including its consolidated subsidiaries, is made known
              to us by others within those entities, particularly during the
              period in which this report is being prepared;

          (b) Evaluated the effectiveness of the registrant's disclosure
              controls and procedures, and presented in this report our
              conclusions about the effectiveness of the disclosure controls and
              procedures as of the end of the period covered by this report
              based on such evaluation; and

          (c) Disclosed in this report any change in the registrant's internal
              control over financial reporting that occurred during the
              registrant's most recent fiscal quarter (the registrant's fourth
              fiscal quarter in the case of an annual report) that has
              materially affected, or is reasonably likely to material affect,
              the registrant's internal control over financial reporting; and

     5. The registrant's other certifying officer(s) and I have disclosed, based
        on our most recent evaluation of internal control over financial
        reporting, to the registrant's auditors and the audit committee of the
        registrant's board of directors (or persons performing the equivalent
        function):

          (a) All significant deficiencies in the design and material weaknesses
              in the design or operation of internal controls over financial
              reporting which are reasonably likely to adversely affect the
              registrant's ability to record, process, summarize and report
              financial information; and

          (b) Any fraud, whether or not material, that involves management or
              other employees who have a significant role in the registrant's
              internal control over financial reporting.

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Date: June 18, 2004                                                        /s/ J. RONALD HANSEN
                                                         --------------------------------------------------------
                                                                             J. Ronald Hansen
                                                              Vice President -- Finance & Administration and
                                                                         Chief Financial Officer
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