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).
Modifications to improve the efficiency of the S.S. Vacuum Pump.
| Identifier | ExFiles\Box 64\1\ scan0039 | |
| Date | 22th May 1929 | |
| X7510 To BY.{R.W. Bailey - Chief Engineer} from Hs{Lord Ernest Hives - Chair}/ACL. c. to E.{Mr Elliott - Chief Engineer} Wor.{Arthur Wormald - General Works Manager} Hs{Lord Ernest Hives - Chair}/ACL2/LG 22.5.29. S.S. VACUUM PUMP. We have proved that the efficiency of the SS.{S. Smith} Vacuum pump is appreciably increased by enlarging the lower - or suction ports - in both the piston and cylinder. The ports have been increased in depth from .062 to .125 as shewn on appended prints. We find it is very important to ensure that these ports - i.e. the piston port and cyl. ports - are in correct registration at the ends of the stroke. To ensure that this is so after assembly, the cover plugs over the exhaust and suction ports should not be soldered in position until after the cyl. has had a trial assembly with the piston on the particular crankcase. Washers of varying thickness could be employed under the cyl. base to obtain the correct adjustment. We recommend that the modifications shewn on V.640/1 be employed on all future SS.{S. Smith} Vacuum pumps. Hs{Lord Ernest Hives - Chair}/A.{Mr Adams} C. Lovesey. | ||