Document Vj36rYj1RM5BYm1rbnwkLxjrj

UM 1 0M Af CARBIDE UJ ffrr> P<05 CORPORATION UJ Rtf PC> V" ptpy J PS CHEMICALS AMD PLASTICS DIVISION TEXAS MU. PL AMT ----- 5 15 ACCIDENT INVESTIGATION REPORT Piiait ind..uifii_is ihfln. -Aitnifv vatif H/l hy Initiallity at J`rrrll rnUntl wDept. Hd (s) I. w, A. Mazzolin^ Mgr*. Dept a. F. S. Provenzano 4. S & FP w R t & Bpts s. J. B. Leverton e R. J. Taylor Accident Report* 11107 int ntrtintinn* B-5 Rupture Disc Failure Accountable Ocaorment;__Solvent Vinyl Resina Building*: 115Date nf Accident: 10/6/78 Potential Accident Classification: Q3 0 CD 3 Actual Accident Class if icat ion: - n a b n Probability Recurrence: Q] Rawota G3 Low jffl Made rite [j] Hifft Loss Analysis A. $ + - S + c. L JJHL 4.1QQ Itoterisi Loss ($ Loss/Unit x # Units X in lbs; pis; etc.) Product Mixup (Rerun, Devaluation.atc.) Equipment Damage ($ to Replaee/tapair) + 0. L Business Interruption" ($ IMI Loss) +E L Med./Comp. Constant + T. L 1ML t 4,300 Productivity Loss (Est. fcnbaurs x S/Manhoui) and/or Claims Casts Tots I Loss DETAILED.., REPORT Accident Su--rv The 8-inch S-90 rupture disc on B-5 autoclave. Bldg. 115, ruptured following a routine transfer with a partial release of the autoclave contents. ImfBaUMtiflfl The Operator transferred the contents of B-6 into B5 per S.O.P. He applied heat to the autoclave. The temperature rose to 59* and the pressure to 79 psig. At this point an 8", S-90 rupture disc rated at 105 psig blew causing some vinyl chloride and varnish in the autoclave to be released out the vent. After the Operator confirmed a premature failure, he closed the hand valve under the rupture disc from ground level. The venting lasted approximately 30 seconds with the loss of 16,000 pounds of varnish and 250 pounds of vapor. The incident was r ported to EP and XH Departments. Unit procedure was followed but no toxic gas or fire alarms were turned in. The rupture disc had been in service for about 8 months. UCC 093545 (Include Coim ihutimf Flimsy 1. Cause of the release was due to premature failure of an S-90 rupture disc. Cause of the premature failure is-still under investigation. NOTE: This release highlighted some deficiencies in our Unit Flammable Vapor Cloud procedure. Some of the Action Plans below will eliminate those deficiencies. PREVENTATIVE AND CORRECTIVE ACTIONS .1 INCLUDE RESPONSIBILITY AMD MRPI.ETItlN tlATE) 1. Revise unit procedure concerning premature failure. (Consider actuation of sp.rinkier system; sounding alarm; mini- Air Pak; etc.) PDS 2. Inquire into risks of higher pressure tests w/Otto Cox. PDS 3. Send the disc to BS&B. JDV 4. Review incident with BS&B experts. JDV 5. BS&B analysis obtained. PDS 6. Install sprinkler system actuators inside Bldg. 115 Control Room JRR 7. Review & strengthen rupture disc installation procedures. PDS 12/1 11/20 complet< 10/27. complet' 10/27 12/1 1/1/79 1/1/79 'repared by: I tenths r: Chairperson P.D. Smith A.P. Yalcinkaya J. D. Summers Date of Investigation: _ Oct. 19, 1978 Member: _... W. A. Maz7Cil ini Member: UCC 093546