Flow tolerances as tight as this are only possible if entrance and exit conditions of the orifice are closely controlled. This provides far more accuracy than an orifice specified by hole tolerance. An ordinary hole held to a very tight tolerance will not result in a tight flow tolerance.
Constructed entirely of stainless steel, the 5.5 mm Insert Orifice is available in a range of Lohm (Lohm is a measure of flow resistance) rates and certain models are offered with an integral safety screen.
Installation is simple using Lee's field-proven controlled expansion principle which provides retention and creates a leak tight seal that prevents bypass leakage. To install, simply insert the orifice into a drilled hole and drive the expansion pin into the orifice body to seal and lock the orifice in place.