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).
Endurance test of a Ph.III No.1 unit, detailing a big end bearing failure and performance data.
| Identifier | ExFiles\Box 114\2\ scan0212 | |
| Date | 11th November 1935 | |
| To E.{Mr Elliott - Chief Engineer} c. to Wor.{Arthur Wormald - General Works Manager} c. to Hy.{Tom Haldenby - Plant Engineer} HS{Lord Ernest Hives - Chair}/Swdl.{Len H. Swindell}34/KW.11.11.35. Endurance Test on Ph.III - No.1 Unit. After carrying out development work on this unit for 80 hours, including 1 hour's continuous run at 4500 r.p.m. it was decided to continue the running by an endurance test at 4,000 r.p.m. This unit was to the original specification RHC{R. H. Coverley - Production Engineer}/WSC.{W. S. Cassel}6/EP.{G. Eric Platford - Chief Quality Engineer}4.7.34. incorporating Marine type of rods with white metal bearings throughout, and semi-split pistons. After 25 hours at 4,000 r.p.m. No.3 big end failed, the metal having run out completely from the forked and the blade rod bearings. The remaining big ends showed signs of cracking up, but the main bearings other than being embedded with fine particles of white metal were in very good condition. The front, middle and rear bearings were grooved but the inter. main bearings were not grooved. With regard to the crankshaft, the crank journals had the single hole feed and it was noticeable that the crank was highly polished on the opposite side to the hole. During the run several valve springs, which were of the single type E.85315/6/7, were broken, also several of the original type of duralumin push rods. The latter we replaced by steel rods as the strengthened type of duralumin rods were not available, and there was no further trouble. The condition under which the run was carried out was as follows :- 136 BHP. developed at 4,000 r.p.m. with the exhaust system fitted. Price's Motorine 'C' oil - inlet 95-100°C. outlet 115-120°C. pressure 35 lbs/sq.in. Average oil consumption 2½ pts/hr. | ||