Jordan Valve Mark HPX and HPAX Series Globe & Angle Style Панель управления User Manual

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Valve Plug Maintenance

Remove the valve plug and stem assembly (key

20, 22) using the trim removal procedures.

Follow the instructions for your specific equip

ment:

2.1.

For the Mark HPX2D and HPAX2 valves,

remove both halves of the piston rings

(key 11) from the grooves in the

valve

plug.

2.2.

For the Mark HPX5T and HPAX5 valves,

pry the retaining ring (key 27) off the

valve plug with a screwdriver. Gently

slide the backup ring (key 28) and seal

ring (key 29) of the valve plug.

For replacement of the valve plug stem drive

out the groove pin from the valve plug

and unscrew the stem.

Note: When replacing a valve plug always re

place the corresponding valve plug stem. The

stem and pin should be ordered as an

assembly.

Screw the stem (key 20) into the valve plug (key

22), tightening the stem to the recommended

torque given in Table 2. Determine the correct

drill size (Table 2) and drill through the

stem using the groove pinhole as a guide.

To lock the assembly, drive in the groove pin

(key 10).

If required, lap the seating surfaces prior to

installing the piston rings or seat ring. Use the

trim replacement instructions for the piston

ring and seat ring installation and reassembly of

the valve.

Seat Lapping

With metal-to-metal seating in any valve, a small amount

of leaking can be expected. If the leakage becomes

excessive it is possible to limit the valve leakage by seat

lapping.

Eliminate any deep nicks through machining

rather than grinding.

Apply a good quality lapping compound mixture

of 280 to 600-grit to the bottom of the valve plug.

The Mark HP Series designs have spiral

gaskets, which are compressed to provide

their seal. Spiral-wound gaskets are designed for

single service. If they are ever disturbed they will

need to be replaced on reassembly. The

previously used gasket may be used to lap the

seat but the gasket must be replaced with a new

gasket.

Using the instructions under trim replacement,

install “old” seat ring gasket, seat ring, cage and

the “old” bonnet gasket.

Install the valve plug and stem assembly without

piston rings or seal ring into the cage.

Slip the bonnet over the valve stem. Fasten the

bonnet by securing four of the hex nuts.

It will be necessary to attach a handle to the

valve stem. This could be a piece of strap metal

attached by stem locknuts.

Turn the handle alternately in both directions

thereby lapping the seat, taking care not

to gull the seat and plug.

When complete, disassemble stopping to mark

the positions of the cage with a soft-tipped

marker.

10.

Clean the seating surfaces, replace the gaskets

and reassemble. Test for leakage and repeat the

lapping procedure if required.

11.

The position of the seat ring and cage must re-

main constant to preserve the effects of lapping.

Ensure that when parts are removed for

maintenance and cleaning, they are returned to

their original position.

Trim Replacement

Complete all necessary maintenance on the trim includ-

ing cleaning all gasket surfaces. Inspect sealing sur-

faces. Nicks and scratches will prevent the gasket from

sealing properly.

1. Replace:

1.1.

Seat Ring Gasket (key 24)

1.2.

Seat Ring (key 23)

1.3.

Cage (key 12)

1.4.

Piston Rings (key 11)

1.5.

Seal Rings (key 29)

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