Flowserve Valtek Mark 200 - Manual (Page 12)

Mark 200 Control Valve FCD VLENIM0200– 12/12
12
8.1 DIN Valve Quick-check
Prior to start-up, check the control valve by following these steps:
WARNING: Due to the risk of injury, it is prohibited to work
between the yoke/columns while the valve is in operation.
1. Stroke the valve and observe the plug position indicator on the stem
clamp compared to the stroke indicator plate. The plug should change
position in a smooth, linear fashion.
NOTE: Due to excessive friction, graphite packing can cause the plug
stem to move in a jerky fashion.
2. Check for full stroke by making appropriate instrument signal change.
3. Check packing box bolting for the correct adjustment. Refer to the
packing installation manual for specific details on maintaining the style
of packing supplied.
CAUTION: Do not overtighten packing. This can cause
excessive packing wear and high stem friction that may
impede plug movement.
4. After a temperature excursion has occurred, bonnet flange bolting
should be retorqued to ensure bonnet gaskets do not leak. See Table 4.
Table 4: Recommended DIN Body Bolt Torque Values
Bolt Size
PN 160 / Body Material
1.0619, 1.5419 1.7357 1.7379
(mm) ft lb N m ft lb N m ft lb N m
M24 265 360 265 360 300 405
M27 385 525 385 525 410 555
M30 410 555 415 565 480 650
M33 630 860 650 885 740 1000
M39 1220 1650 1220 1650 1250 1700
M42 1400 1900 1400 1900 1550 2100
M52 3250 4400 3250 4400 3250 4400
Bolt Size
PN 250 / Body Material
1.0619, 1.5419, 1.7357 1.7379
(mm) ft lb N m ft lb N m
M24 265 360 280 (300)* 380 (410)*
M30 427 580 500 680
M39 1150 1570 1220 1660
M45 2060 2800 2060 2800
M48 2500 3400 2500 3400
M56 4050 5500 4050 5500
M72 8550 11600 8550 11600
* Nominal Size DN 80 only
9 DIN Valve Maintenance
At least once every six months, check for proper operation by following
the preventative maintenance steps outlined below. These steps can be
performed while the valve is in-line and, in some cases, without interrupting
service. If an internal problem is suspected, refer to the “Valve Disassembly
and Reassembly” section. If multiple checks in line without claim (record) it
is allowed to extend the maintenance interval by risk of plant operator.
1. Look for signs of gasket leakage through the end flanges and bonnet.
Retorque flange and bonnet bolting (if required). See Table 4.
2. Check for fluid leakage to the atmosphere through the body drain plug, if
applicable.
3. Examine the valve for damage caused by corrosive fumes or process
drippings.
4. Clean valve and repaint areas of severe oxidation.
5. Check packing box bolting for proper tightness. Refer to the packing
installation manual for specific details on maintaining the style of
packing supplied.
CAUTION: Do not overtighten packing. This can cause exces-
sive packing wear and high stem friction that may impede
stem movement.
6. If the valve is supplied with a lubricator fitting, check lubricant supply
and add lubricant if necessary. See product documentation or contact
the Flowserve representative.
7. If possible, stroke the valve and check for smooth, full-stroke operation.
Unsteady stem movement could indicate an internal valve problem.
NOTE: Due to excessive friction, graphite packing can cause the plug
stem to move in a jerky fashion.
WARNING: Keep hands, hair and clothing away from all moving
parts when operating the valve. Failure to do so can cause
serious injury.
8. Make sure positioner linkage and stem clamp or coupling pieces are
securely fastened. If the stem clamp or coupling pieces are loose, check
plug thread engagement (refer to the “Reassembling the Body” section
for the correct procedure on aligning the plug with the seat.) Tighten
stem clamp nut or counter nut.
9. Ensure all accessories, brackets and bolting are securely fastened.
10. Clean any dirt and other foreign material from the plug stem.