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Sample Case

Balance Chamber

The valve stroke on a precision assembly is held to +/- .001”. An internal component has flatness held to .002” across surfaces with diameters 1.050” and .720”. An automatic unscrewing core forms extremely fine 40 threads per inch on a 1.216”I.D. in the outer component.

Poppet

The poppet is produced with a collapsible core mold with flexing elements that collapse inward during the initial stage of ejection to release the 1.500” and 1.374” O-ring grooves. A circular run-out of .004” to a datum reference is held on 6 critical diameters. Diameters of 1.562” and 1.781” are held to +/- .002”.

Regulator

A pump regulator is produced from a 3-plate mold with 5 independently controlled unwinding core pulls to form thread details and runs fully automatic production. Each core pull has interchangeable inserts for different thread specifications and port size openings. The part is molded in 33% glass filled nylon. A vacuum is used to pull air from cavities to avoid blemishes on critical sealing surfaces.

Retainer

The 10-24 UNC-2A thread on this retainer is formed with side cores below the parting line surface and core detail, and activated during ejection with a dual purpose cam mechanism.

	Gauge This precision assembly requires a pointer-indicator to be held to +/- 3 degrees, the concentricity in a molded polycarbonate lens to be held to +/- .002", and a hermetic seal of the assembly through sonic welding.
	Sleeve A sleeve is molded in 50% glass filled nylon with concentricity of four diameters held within 0.005” to a common datum reference.

Pump Housing

Dimensions of an internal diameter and occlusion radius are held within +/- .002” on a pump housing with a thick wall section.

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