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).
Tests and results for new Bentley starter motor poles made from special Lohys steel.
| Identifier | ExFiles\Box 62\1\ scan0241 | |
| Date | 24th April 1934 | |
| x6134 By.{R.W. Bailey - Chief Engineer} From Hs{Lord Ernest Hives - Chair}/Wst. c. to E.{Mr Elliott - Chief Engineer} Hs{Lord Ernest Hives - Chair}/Wst.9/MA.24.4.34. BENTLEY STARTER MOTOR POLES. We have now tested a set of Bentley starter motor poles to drawing DB{Donald Bastow - Suspensions}297 made in special Lohys material instead of the usual pole steel. This material was considered to have a higher permeability than the usual existing standard pole steel and should therefore give a better torque and BHP. at the higher flux densities in the motor. Our tests confirmed this. Actually at the maximum currents corresponding to the stalling torque condition of the motor, the efficiency improved from .170" to .265"which is a very big improvement indeed. The improvement in BHP. at this point was from .410" to .637". At the lower flux densities only a slight improvement was noticed, as was to be expected. These poles have given such remarkably improved results that we consider they should be adopted on production as soon as possible in place of the standard pole, and we should like to know if this material can be obtained satisfactorily on production without any difficulty in which case we will arrange to issue a standardisation sheet accordingly. Hs{Lord Ernest Hives - Chair}/Wst, | ||