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 K.L.G. Sparking Plugs regarding the production and specifications of plugs for the Phantom III and Merlin engines.
| Identifier | ExFiles\Box 162\4\ img148 | |
| Date | 28th May 1936 | |
| K·L·G Sparking Plugs Limited CONTRACTORS TO THE AIR MINISTRY, ADMIRALTY, WAR OFFICE & FOREIGN GOVERNMENTS. Sole Manufacturers of "KLG" Sparking Plugs, also Jigs and Precision Tools PUTNEY VALE, LONDON, S.W.15 Telephone Putney 2671 (Four Lines) Telegrams: Kaelgee, Phone, London. PLEASE REFER TO TECHNICAL DEPT. AND QUOTE REFERENCE CMC/MEN IN YOUR REPLY 28th May, 1936. Messrs. Rolls-Royce, Ltd., Derby. Gentlemen, For the attention of Mr. West - Hs{Lord Ernest Hives - Chair}/Wst.8/JH. We are very pleased to receive your letter of May 27th and, as requested, are immediately making up six dozen K.L.G. plugs type 921 with the modified firing point as applied to the type 850-D.{John DeLooze - Company Secretary} These we understand are for test in the Phantom III engine. With reference to type 868 plugs for the Merlin engine, we would inform you that the Air Ministry specification for 14 m.m. plugs embodies a torsional test of 40 ft. lbs. to be applied to the main hexagon when the plug is screwed into the cylinder. As we advised you we apply this test continuously to every delivery of new material and we can assure you that all of our plugs will stand 50 ft. lbs. minimum. We have also investigated the amount of pressure which we apply in tightening the gland nut into the body and have ascertained this to be 37 ft. lbs. We consider this pressure fully sufficient for the purpose and, unless you have found a definite reason for it, we should not advise any additional pressure being applied before the plugs are used. Yours faithfully, p.p. K.L.G. SPARKING PLUGS LIMITED. Director. | ||