Document jyomE46rv0e0kj8qBa49b80aZ

Tenneco .deals, Inc. (COMPANY) (LCE-10-79/ FLE-16-79) TO: c. E. Crain DATE: April 12, 1979 FOR: Distribution FROM: l, c. Elliott/F. L, Eyerraan RE: Safety Relief Valves On VCM Filters, L-302A,B,C,D,E&F (CAR 97067) Reduced Venting From Safety/Relief Valves The VCM charging on computer control was modified on March 30, 1979. The VCM charge valve, 31-FV-17, now opens before the charge pump starts instead of vice versa. No incidents of hainnering or lifting of filter safety/relief valves have been reported since this change was made. The pump discharge pressure after the pump starts now peaks out at about 140 psig as opposed to 180 psig before the program change was made. Safety/Relief Valve Pressure Settings In accordance with the ASME vessel coding, the MAWP for the filters is 263 psig at 120F. Presently, the filter's safety/relief valves are set at 265 psig @ 196F with 150# inlet flanges. These parameters are in the jurisdiction of 300 lb flange rating. In order to operate safely in the 150 psig flange range, the pressure setting should be lowered to 240 psig. The new safety/relief valve installation to replace existing thermal relief valves on L-302A,B,C&D shall have this new setting. L, C. Elliott LCEjFLE/cjm cc: L. L. Bird C, A. Hendricks T. T. Moore L. Cox J. R. Beeson D, O'Connor C. S. Stutts J, R. Anslow S. E. Richter Engineering File 60.38 TEN 1315 turn ***