Metal spraying aids lubrication

For more than a quarter of a century the technique of metal spraying has been a commercial success in this country, but it is only in the past few years that its possibilities as an aid to lubrication have been fully recognised. Exhaustive tests have shown that metal‐sprayed journals, for example, have an increased life of at least 40 per cent, due to the capacity of the sprayed metal for retaining an oil film. While the metal spraying method of building up worn parts cannot be applied universally to all worn lubricated surfaces— for instance, it is unsuitable for certain components which are subject to appreciable shock, such as cams, gear teeth, etc.,—it offers an efficient means of salvaging much material that would normally be discarded, and simultaneously increases the efficiency of the built up part, when this has to be lubricated.