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).
Standardisation of parts to reduce the number of holes in the rear silencer pipe to cure a whistling sound.
| Identifier | ExFiles\Box 171\5\ img063 | |
| Date | 7th October 1938 | |
| RR 755A (10H) (4988) 19/10/37 C.E.Co. COMPLETED 24.11.38. 25/30 H.P. STANDARDISATION OF PARTS Date Issued 7.10.38. Sheet No. W.6. Drg. No. RR.1804. L.O.P.S. Description: REDUCE NUMBER OF HOLES IN RR.1804 PIPE IN REAR SILENCER FROM 109 to 30 EQUALLY SPACED. Purpose: Cure whistle from rear silencer. Brief Report and Remarks: A number of Wraith silencers have a tendency to whistle, and to cure this we have to reduce the number of expansion holes from 109 to 30. This does not in any way effect the BHP. figures as the holes only communicate with a resonance chamber. When recommended for Introduction: Report References: By: SY. Rm{William Robotham - Chief Engineer}: RR. Da{Bernard Day - Chassis Design}: DA.{Bernard Day - Chassis Design} Mx{John H Maddocks - Chief Proving Officer}: MY. Old Parts - Material: £0.1.4. Labour: £0.1.7. Burden: £0.2.6. Total: £0.6.3. New Parts - Material: £0.1.4. Labour: £0.0.11. Burden: £0.1.7. Total: £0.4.10. Decrease in Cost £0.1.5. G/Rb.{R. Bowen} 5.11.38. Production Position and Comments: Cost of Tools £4.0.0. Reduced number of holes in RR.1804 rear silencer pipe to cure whistle can be effected without scrap at the 1st. chassis in 'B' series. This modification will provide a saving of 1/4 1/2d. per chassis and involve a tool cost of £4.0.0d. The tool cost of £4.0.0d. will be recovered after producing 60 chassis i.e. at the 60th. chassis in 'B' series. RHO. Authorisation to Proceed. Introduce on the 1 Chassis in B Series. Signature Sg.{Arthur F. Sidgreaves - MD} G Date 22.11.38. Signature Hs.{Lord Ernest Hives - Chair} Hs.{Lord Ernest Hives - Chair} Date 22.11.38. | ||