Instruction Manual
D103358X012
24000F Valves
February 2021
5
2. Loosen the packing spring load by removing the packing follower (key 10).
Remove the plug and stem assembly by pulling it out through the bottom of the bonnet (key 8) while rotating the
stem (key 5). This will help prevent damage to the packing components.
Note
Handle the parts carefully to avoid damaging the seating and guiding surfaces. Wipe the parts with a clean soft cloth and examine
for signs of wear or damage.
3. To remove the seat ring (key 2), use a 5/8 inch socket wrench. Clean the seat ring thoroughly and examine for signs
of wear or damage.
4. Low Flow Trims:
a. For Baumann 151 trim (figure 5) unscrew the seat subassembly. When reassembling, hand tighten the
subassembly (key 51) and then rotate 1/8 of a turn with the 5/8 inch socket to lock in place.
Note
If changing to Baumann 151 trim, for correct flow characteristics, be sure the valve is reversed in the pipeline so that flow direction
is flow-to-close.
gland (key 23) and insert (key 25). Replace the insert (key 25), making sure that the tapered portion faces up. If
replacement of the housing (key 26) is required, use a 5/8 inch socket wrench.
Lapping the Valve Seat
If valve seat leakage becomes excessive, it may be necessary to lap the valve seat.
Lapping is the process of mating the valve plug to the seat ring, with an abrasive to produce a close fit. When valve seat
leakage becomes excessive, lapping becomes necessary. The plug and seat ring seating surfaces should be free of
large scratches or dents and the contact surface of the seats should be as narrow as possible.
1. Disassemble the valve body and remove the plug and stem assembly (keys 4 and 5) as directed in the previous Valve
Body Disassembly section in this instruction manual.
2. Use a good quality lapping compound with a mixture that contains 280 to 600 grit. Apply at several spots around
the plug seating surface. Replace the plug and stem carefully in the bonnet.
3. Install the bonnet (key 8) into the valve body, without gasket and hand tighten. The bonnet will serve as a guide
during the lapping operation.
4. Lap the valve by applying a slight pressure on the stem and rotate the stem in short oscillating strokes
approximately 8 to 10 times or until you see an even and complete lap line. The plug should be intermittently lifted
and turned 90 degrees while lapping to keep the plug and seat ring concentric.
5. Clean the valve seat and plug
(key 4) thoroughly when lapping is complete, removing all traces of lapping
compound.
6. For the NPS 1 integral seat body, inspect internal seating surface for wear or damage and replace if necessary.
Replacing Packing
Refer to figure 2 and the standard and optional packing constructions (figures 7, 8, and 9)
to determine the packing
that has been preinstalled in your valve.
