Chapter 14. -PIPING, FITTINGS, AND VALVES 



38,128 



Figure 14-30.— Examples of MSS standard identification markings for valves, 



fittings, flanges, and unions. 



SAFETY PRECAUTIONS 



Most piping system repairs involve breaking 

 joints in the piping system. Before breaking 

 joints in- any shipboard piping system, be sure 

 the following precautions are observed: 



1. Be sure there is no pressure on the line. 

 This is important in practically all systems, but 

 it is of vital importance in steam lines, hot 

 water lines, and any salt water lines that may 

 have a direct connection with the sea. It is not 

 enough to merely close the valves; the valves 



389 



