Letter to The British Thermostat Co. Ltd. discussing soldering methods for a valve head.
| Identifier | ExFiles\Box 156\1\ scan0281 | |
| Date | 9th October 1937 | |
| 1328 Rm {William Robotham - Chief Engineer} /Std.7/MH. {M. Huckerby} Messrs. The British Thermostat Co. Ltd., Windmill Road, Sunbury-on-Thames. Middx. 9th. October 1937. For the attention of Mr. Martin Hurst. Dear Sirs, We have received your letter of the 7th. inst. for which we thank you, and note your explanation of the reason why the valve head came loose, which seems a logical one. However, we would submit that if the valve stem end were tinned before screwing the head on, the locking solder would run into the thread and the heat necessary to sweat the ball valve casing to the head would not be sufficient to destroy the locking, at the worst it would only loosen it while the valve was hot. As regards the sweating of the valve cap to the valve head, if the cap is tinned internally and the valve head nut tinned externally, the only heat necessary would be just enough to allow the casing to slide onto the nut. It would then be soldered when it cooled. The locking of the valve head would easily be checked by warming the thermostat until valve is off seat and then endeavouring to rotate the valve. A final precaution, of course, would be to keep the thermostat erect until the solder head solidified. The alternatives are either - (a) To abandon the ball valve - we do not wish to do this if possible. (b) To attach the ball valve casing by three blobs | ||
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).