From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Test-bed work log comparing the performance and failure points of six different piston designs.
| Identifier | ExFiles\Box 86\2\ scan0145 | |
| Date | 27th October 1933 | |
| TEST-BED WORK. HOURS RUN PISTON | UNIT | FAILURE ROW 1 PISTON: PIECE No E.B. 495, F/P 404 DIE CAST., Mx.{John H Maddocks - Chief Proving Officer} BEDDING, SHRUNK-ON GUD. PINS UNIT: SPEC: C.XII, RHC.{R. H. Coverley - Production Engineer}/WSCG/AP 8-8-33, CYL. BLOCK, SHORT TYPE BARRELS. HOURS RUN: PISTONS CRACKING. CRACKS JUST STARTING FROM HOLES IN SLOT. TEST: { 4 1/2 HOURS @ 4000 R.P.M., 1 1/2 " " 4250 " } F.T. FAILURE: CRACKS ROW 2 PISTON: PIECE No E.B. 495, P.I. 404 DIE CAST., GRINDING Ex. 11480, SHRUNK-ON GUD. PINS UNIT: SPEC: C.XI, RHC{R. H. Coverley - Production Engineer}/WSC{W. S. Cassel}9/AP 19-7-33, CYL. BLOCK, SHORT BARRELS. HOURS RUN: NO FAILURE, PISTONS O.K. TEST: { 1 1/2 HOURS @ 4000 R.P.M., 3 3/4 " " 4250 " } F.T. TEST STOPPED SIMILAR PISTONS HAVING FAILED ON THE ROAD SEE TEST D ROW 3 PISTON: PIECE No E.B. 495, GRINDING { TOP .20/.25, LOWER E.B.500 }, SHRUNK-ON GUD. PINS. UNIT: SPEC: C.XI, RHC{R. H. Coverley - Production Engineer}/WSC{W. S. Cassel}1/AP 11-9-33, CYL. BLOCK., LONG TYPE BARRELS. HOURS RUN: COLD KNOCKS JUST AUDIBLE. CRACKS FOUND ACROSS TOP OF GUDGEON PIN BOSS PISTONS 3 & 6 SKIRTS ARE O.K. TEST: { 12 HOURS @ 4000 R.P.M., 4 " " 4250 " } F.T. FAILURE: CRACKS ROW 4 PISTON: PIECE No LEC. 3493, SEMI-SPLIT TYPE, GRINDING E.B. 303, SHRUNK-ON GUD. PINS. UNIT: SPEC: B.1., RHC{R. H. Coverley - Production Engineer}/WSC{W. S. Cassel}10/AP 27-10-33, CYL. BLOCK., LONG TYPE BARRELS. HOURS RUN: NO. 4 PISTON SEIZURE. Nos. 1, 2, 3, 5, 6. MARKS OF INSUFFICIENT CLEARANCE. TEST: { 5 HOURS @ 3000 R.P.M., 6 3/4 " " 4000 ", 2 3/4 " " 4250 " } F.T. FAILURE: HIGH-MARKS ROW 5 PISTON: PIECE No LEC. 3667, SEMI-SPLIT TYPE, GRINDING TO L.E.C.3667, MOD. LEC. 3667 UNIT: SPEC: B.4., RHC{R. H. Coverley - Production Engineer}/W.S.C.5/AP 26-10-33, CYL. BLOCK., LONG TYPE BARRELS, MOD. LEC. 3667 HOURS RUN: PISTONS CRACKING. CRACKS JUST STARTING AT TOP SIDE OF GUD-PIN BOSS. TEST: { 6 1/4 HOURS @ 4000 R.P.M., 5 1/4 " " 4250 ", 50 MINS " " 4500 " } F.T. FAILURE: CRACK, (SECTION) ROW 6 PISTON: PIECE No EX. 12610, "AEROLITE", PUSH-FIT GUD PINS. UNIT: SPEC: B.7., RHC{R. H. Coverley - Production Engineer}/WSC{W. S. Cassel}5/AP 23-10-33, CYL. BLOCK., SHORT TYPE BARRELS. HOURS RUN: NO. 6 PISTON SEIZED, BEDDING MODIFIED, SEE HS{Lord Ernest Hives - Chair}/MHS. 25-10-33. No. 4 PISTON SEIZED. No. 2 PISTON SLIGHT CRACK FROM END OF HORIZONTAL SLOT. IMMEDIATELY BELOW SCRAPER RING ON PRESSURE SIDE TO TOP END OF LONGITUDINAL GROOVE BELOW. TEST: { 10 HOURS 50 MINS AT 4000 R.P.M., 8 HOURS 30 " " " 4250 ", 1 " 40 " " " 4500 " } F.T. FAILURE: CRACK | ||