Flowserve Valtek Mark Six Quick Start Manual

Valtek Mark Six Cryogenic
Service Control Valves
GENERAL INFORMATION
The following instructions are designed to assist in
unpacking, installing and performing maintenance
required for the Valtek
control valves.
This publication does not contain information on install-
ing, maintaining, troubleshooting, calibrating, and oper-
ating Valtek positioners. Refer to the appropriate Valtek
Control Products Installation, Operation, Maintenance
Instruction when this information is required.
To avoid possible injury to personnel or dam-
age to valve parts, WARNING and CAUTION
notes must be strictly adhered to. Modifying
this product, substituting nonfactory parts, or
inferior parts, or using maintenance procedures
other than outlined could drastically affect per-
formance, void product warranties and be haz-
ardous to personnel and equipment.
The Valtek Mark Six is a globe style, single seat, top
entry valve with a fabricated cold box extension for use
in cryogenic applications down to minus 423
weight is kept to a minimum to reduce boil-off on valve
cool-down. The extension design permits easy access
and removal of the valve trim through the cold box. The
Mark Six utilizes a spring-energized Teflon seal or a
small vent hole through the plug seal to permit only a
small amount of liquefied gas into the bonnet areas
where it vaporizes and provides a vapor barrier be-
tween the liquefied gas and the packing. The pressure
resulting from the vaporization of the liquid keeps any
more liquid from passing into the bonnet area. The
small amount of vaporized liquid is not sufficient to
produce high pressures at shut-down.
Rev. 1/88 Valtek No. 49016
® Mark Six cryogenic service
°
F. Body
Unpacking
1. Before installation, check the packing list against the
materials received. Lists describing the valve and
accessories are included with each valve.
2. When lifting valve from shipping container, position
lifting straps to avoid damage to tubing and mounted
accessories. Most valves may be lifted by the
actuator lifting ring. If one is not provided use lifting
straps around yoke legs to lift valve.
3. In the event of shipping damage, contact your ship-
per immediately.
4. Should any problem arise, contact your Valtek Con-
trol Products representative.
Installation
Mark Six valves with vented plugs should always be
mounted with the extension and actuator within 15
vertical. Mark Six valves using spring-energized Teflon
plug head seals may be mounted horizontally.
1. Before installation, clean the line of all dirt, scale,
welding chips and other foreign material.
2. Check flow direction to be sure the valve is installed
correctly. Flow should be over the plug for fail-closed
valves, and under the plug for fail-open valves. Flow
direction is indicated by an arrow on the bonnet
flange.
3. Provide proper overhead clearance above the ac-
tuator to allow for actuator removal and trim inspec-
tion, should it be necessary. Disassembly clearance
depends on the length of the cold box extension and
the valve size. To estimate required clearance, add
the length of the extension to the appropriate dis-
tance recommended for the particular valve size.
°
of
6-1