EXHIBIT 23.1 CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM Graham Corporation We consent to the incorporation by reference in Registration Statement Nos. 2-82432, 2-82275, 33-82432, 333-00401, and 333-113426 and Post-Effective Amendments No. 1 to Registration Statement Nos. 33-82432 and 333-113426 of Graham Corporation and subsidiaries on Forms S-3 and S-8 of our reports dated June 9, 2004, appearing in this Annual Report on Form 10-K of Graham Corporation and subsidiaries for the year ended March 31, 2004. /s/Deloitte & Touche LLP Deloitte & Touche LLP Rochester, New York June 18, 2004