It should be the meaning of BREATH VALVE, breather valve
It should be American Copeland company, BV series valves;
End code description link example (matching) BV PL endpoint endpoint oblique butt welding wire socket, socket welding (SWF) FL flange connection flange connecting pipe in the AutoCAD Plant 3D in connection with the pipe elements form in many ways, details are as follows: the end code description link example (matching) PL endpoint, outside the wire socket socketweld (SWF) BV oblique butt THDM external screw thread connection endpoint (THDF) THDF (THDM) SW screw thread connection wire socket welding socket welding flange connection flange connection FL WF flat flat flange link (FL) LAP (PL) GRV lap lap ring groove is connected with the connecting groove (PL) SO loose plate (PL) PPL plastic welding wire plane PSW plastic body adhesive (PPL) LFL LLP LUG straight straight flange lap lug flange (FL) BEL L bell shaped joint, bell and socket welding (SPIG), SPIG socket welding, bell shaped joint and socket welding (BELL) TAP plug cock (PL)
