MIL-P-24503B

Abstract

This specification covers various types, classes and grades of non-woven graphitic packing for steam valve service on Naval ships on which valve stuffing box temperatures are limited to a maximum of 1000 degrees Fahrenheit (&#176;F). <b><u>Intended Use:</u></b> Packing is intended for general shipboard service in valves. Grade I packing is intended for use in valves with noncorrosion-resistant (for example, carbon steel, 400 series stainless steel) stem and packing gland parts. Type I packing is in corrugated ribbon or texture form for use where packing gland dimensions are not uniform or known. Type II packing is similar to type I packing; however, because it is preformed, it is designed for applications in new equipment or equipment where packing gland dimensions are uniform or known and in excellent mechanical condition. Laminated rings require exact stuffing box dimensions to provide an interference fit for proper operation. The die molded ribbon packing requires only a drop in, but not loose, clearance with final gland compression setting the rings for proper operation. Class 1 is intended for use where detrimental material content of the packing need not be controlled beyond normal manufacturing limits. Class 2 is intended for use where detrimental material content must be kept to a minimum. <br>