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).
Letter from Inland Manufacturing Division concerning permissible loadings and hardness specifications for Inlox Bushings.
| Identifier | ExFiles\Box 174\2\ img109 | |
| Date | 22th April 1937 | |
| INLAND MANUFACTURING DIVISION GENERAL MOTORS CORPORATION DAYTON, OHIO April 22, 1937 Rolls Royce, Limited, Derby, England. Attention: Mr. W. A.{Mr Adams} Robotham Gentlemen: With reference to our Mr. H.{Arthur M. Hanbury - Head Complaints} C. Berkeley's letter of March 29th and our shipment of sample parts addressed to your attention, the writer wishes to complete this service with the information you requested concerning our Inlox Bushings, namely, the recommended permissible loadings on the various types. We are attaching hereto blue prints #752492; 752637; 752714; 752717 and 752720 showing some of our typical Inlox bushings along with a deflection chart, which indicates in each case the behavior of each one of the several bushings under a definite loading. As to the safe working loads for these bushings, it would depend somewhat on the particular application, but in general we would say the following should be satisfactory. 752492 - - 1060# 752637 - - 1310# 752714 - - 765# 752717 - - 955# 752720 - - 1100# Parts 752720 and 752717 are 62 durometer hardness, the others are 52 in hardness. In the manner of a general discussion, it might be well for us to state that while greater hardness in the rubber compound always allows a higher load to be carried it will limit the angular flexibility. Also, that bushings designed with a shoulder near the end of the inner-tube will increase the endwise stiffness considerably, as you will notice on the deflection curves attached. | ||