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).
Updated operating temperature specifications for the Wraith Calorstat following a complaint.
| Identifier | ExFiles\Box 156\2\ scan0217 | |
| Date | 21th March 1939 | |
| 1328 To By.{R.W. Bailey - Chief Engineer} from Rm{William Robotham - Chief Engineer}/FJH.{Fred J. Hardy - Chief Dev. Engineer} c. By/NS.{Norman Scott} c. Da.{Bernard Day - Chassis Design} Rm{William Robotham - Chief Engineer}/FJH.{Fred J. Hardy - Chief Dev. Engineer}2/MH.{M. Huckerby}21.3.39. WRAITH CALORSTAT. The drawing of the Wraith Calorstat E.87157 has a note on it concerning the operating temperatures which is not very clear and about which Messrs. S.Smith & Sons have complained. We suggest that the existing note should be deleted and the following one inserted. "With no load on the bellows the stem of the calorstat should commence to move at a temperature of 69°C ± 2°C and should give the full travel of 0.425 at 75°C ± 2°C. With the bellows loaded to 28 lbs. the stem should commence to move at a temperature of 79°C ± 2°C and should give the full travel of 0.425 at 90°C ± 2°C." Rm{William Robotham - Chief Engineer}/FJH.{Fred J. Hardy - Chief Dev. Engineer} | ||