Micro-examination report detailing cracks found on a front suspension lever after a bumper test.
| Identifier | ExFiles\Box 9\5\ 05-page042 | |
| Date | 5th April 1937 | |
| Micro-Examination Report. M.1301. To Rm. {William Robotham - Chief Engineer} R. {Sir Henry Royce} Hs. {Lord Ernest Hives - Chair} BY. {R.W. Bailey - Chief Engineer} B/Hdy. {William Hardy} E {Mr Elliott - Chief Engineer} /Ev. {Ivan Evernden - coachwork} H.P.S. 646 HL.12/AG.5.4.37. Laboratory. FRONT SUSPENSION LEVER GW.795. We understand that this lever, in which cracks were found after a bumper test, was made by Messrs. Bretts Stampings,Ltd., and heat-treated at our works, and that it has not been re-heat-treated at any time after running. One of the cracks at the edge of the lever was curved and had the appearance of a fold produced in forging - see your photograph of the complete lever after magnetic testing. Another crack, also shown in your photograph, ran across the edge of the lever in the direction of the original finishing marks and this crack we have examined under the microscope. As you will see from the attached photomicrograph No. Al,592 the crack is filled with oxide. In photomicrograph No. Al,593, taken after etching, there is a region of decarburisation adjacent to the crack, confirming their presence in the original stamping. Hl. HE Photomicrographs Nos. Al,592/3 att. Lever returned to Rm {William Robotham - Chief Engineer} /Les. | ||
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).