Parr Instrument Bottom Drain Valves - Manual

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Operating & Maintenance Instruction Manual 490M
Bottom Drain Valves
Models A465VB, A465VB2, A485VB, A485VB2 & A560VB
Description
The Parr Instrument Company bottom drain valve is a rising stem, process sampling valve. In the closed position,
the stem of the valve is flush with the inside bottom of the vessel so that there is a minimum of dead space
between the bottom of the vessel and the shut off point of the valve. In the fully open position, the stem is retracted
completely to open a clear passage from the vessel. When the valve is re-closed, any material in this passage will
be pushed back into the reactor by the rising stem. As the plunger moves to the closing end of the stroke, a seal is
established as the plunger contacts the compression ring and compresses the seal.
Installation and Operation
These valves are designed to be installed in the bottom of Parr cylinders that are machined specifically for
installation with a minimum of dead space. Pipe thread sealant tape should be applied to the valve body threads
and then installed turning clockwise into the cylinder. The valve should be tightened sufficiently to seal the pipe
threads and bring the stem of the valve approximately even with the inside bottom of the cylinder.
The valve is opened by turning the handle counterclockwise. The more turns open; the valve will provide a larger
passage for product flow.
The valve is closed by turning the handle clockwise until the plunger meets the compression ring and compresses
the seal.
Typical torque values on the valve handle required to seal the valves are as follows:
A465VB 10 – 15 ft/lbs
A465VB2 10 – 15 ft/lbs
A485VB
5 – 10 ft/lbs
A485VB2 5 – 10 ft/lbs
A560VB 15 – 20 ft/lbs
Significantly more torque should not be required to seal the valves. If the valve is leaking, it is a good indication
that the seal is worn or has been damaged. The valve should be disassembled, inspected, cleaned as required
and seals replaced.
Disassembly of the Bottom Drain Valves
1. Retract the plunger to the fully open position by turning the handle counterclockwise.
2. Loosen the jam nut from the valve body by turning it counterclockwise in relation to the valve body.
3. Loosen the retainer by turning it counterclockwise in relation to the valve body until its threads are clear of the
valve body.
4. Pull the plunger, handle, and retainer out of the valve body together.
5. Remove the lower compression rings and seal. Inspect these parts for wear and replace if necessary.
6. Remove the support pin from the valve body.
7. Remove the upper compression ring and seal. Inspect these parts for wear and replace if necessary.