In the processing and production of pump and valve accessories, the processing of the components of the valve stem should be reasonably determined. First determine the total length of the valve stem, the valve body, valve cover, bracket should be placed as required, from the bottom of the convex body of the valve body sealing surface to the top dimension of the bracket H1 + the thickness of the bearing gland wrench H2+ stem nut more than six The height H3+ thread allowance is the total length of the stem.
It should be noted that in the process of manufacturing the valve stem valve stem, if the valve body and the bonnet end face blank have a pouring riser, it is not convenient to stack, and can be measured separately, or can be placed after roughing and then measured. The length of the stem of the valve stem sealed to the stem end is the upper edge of the valve body passage hole and the H5 in the upper sealing position of the bonnet is measured.
The machining allowance of the two-part flange of the pump valve fitting can be reduced in the measurement, because the upper seal of the valve cover will extend during processing, which can be used as a distance to cancel the size. The length of the polished rod portion below the stem thread is measured from the bottom of the protruding portion of the valve body sealing surface blank to the end of the packing hole. In this position, the threaded portion does not collide with the packing after the packing gland is pressed, and the valve stem can be ensured. The opening height of the threaded ram is sufficient.