Other

Jwi Ltd.

David T Smith

Richard E Pitt

Douglas R McPherson

Victor E Hansen

Harold R Biehl

A paper making machine forming board is described wherein the rate of drainage of the stock through the forming fabric is curtailed and controlled by applying a low positive air pressure (above ambient atmospheric) to the machine side of the forming fabric. Additionally, a controlled level of agitation is induced in the stock on the forming board, providing better initial paper formation.

Pressurized forming board

A method and apparatus are disclosed whereby the rate of drainage of the stock on a Fourdrinier paper making machine can be controlled for the full length of an open surface forming section. A continuous sealed drainage box is used from adjacent the head box slice to the end of the forming section, within which the air pressure can be controlled. In the area adjacent the head box slice drainage is hindered by the use of a positive (above ambient atmospheric) pressure, while further along the forming section the pressure is decreased to a negative value (below ambient atmospheric). Improved paper formation and first pass retention are obtained.

Pressure control forming section

A method and material for the manufacture of improved bearing elements such as annular inner and outer bearing ring blanks for ball, roller and needle bearing assemblies comprising the steps of mixing a powder consisting substantially of iron with ferro-alloy powders of substantially smaller size, each ferro-alloy containing at least 80% iron and the balance being an alloying element, together with graphite powder and a lubricant, compacting the resulting mixture to form a preform, pre-sintering the preform, and then coating the sintered preform with a stop-off and lubricant. The preform is subjected to a plastic deformation of at least 50% in a cold (room temperature) forging operation to produce an article which is at least 98% dense and has approximately the shape of the finished article. This cold forged shape is resintered and annealed, after which the annealed and resintered shape is roll formed into substantially final dimensions. The article can be followed by a suitable heat treatment for hardening the shape.

Cold forced sintered powder metal annular bearing ring blanks

This invention relates to a method of making a valve lifter or the like wherein elemental iron powder is blended with smaller sized powders of manganese, molybdenum, and nickel, or sources of these metals, the resulting mixture is pressed into a coherent preform which is then sintered to cause solid state diffusion and alloying to occur within the preform. The sintered preform is then pressed into a shape which approaches the theoretical density of the metal and has a nearly uniform density carburized and heat treated, the pressing being carried out at ambient temperatures to produce a valve lifter or similar article having superior wearing properties at a lower cost, when compared with present materials and methods of manufacture.

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Monson, MA, United States of America

David T Smith