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).
Cooler testing, detailing failures, and recommendations for future production and reconditioning.
| Identifier | ExFiles\Box 131\5\ scan0015 | |
| Date | 10th November 1937 | |
| -2- failure before), but did not leak on a soldered joint until 400 lbs/sq.in was reached. Of the four failures which we produced at soldered joints, three were at the same point, i.e. where the division plate joins the bottom plate and so prevents perfect metallic contact. The fourth was due to the collapse of a tube. At the end of these tests, all the cooler side plates and top plates were severely bulged, but in spite of this, when cooler was sectionned, there was no sign of the plates tearing away from the tube bulges. Sectionning of the coolers showed an excellent solder bond everywhere, (see attached photographs) and it was only possible to tear off the casing plates by using a large leverage. In many cases the tube tore away with the plates. We therefore conclude that coolers incorporating these modifications should be entirely trouble free in service (providing the standard of workmanship in these sample coolers is maintained). We are, therefore, arranging that all future coolers both new and reconditioned, shall be made in an exactly similar manner to these 5 coolers. We have discussed the reconditioning question with R.Y. and are of the opinion that since rebulging of the tubes is necessary, the reconditioned coolers should be built by using the old casing parts and new tubes with the correct bulge length. The cost of the new tubes to be borne by us since the original design of bulge was our own. Summary. No further trouble should be experienced with coolers built up with modified tubes and casings as per the five tested. All future coolers made for either production or replacement purposes will be identical with these five units and will use the serial index 'A' instead of 'B'. Arrangements should be made with Messrs. Marston for R.R.Ltd. to pay the cost of the new tubes used in the reconditioned coolers. Messrs. Marston have promised us a delivery of 30 new coolers per week to be used for either production or replacement purposes. Rm{William Robotham - Chief Engineer}/Std. | ||