Flowserve TSQVIOM Durco Mach 1 Severe Service Valve IOM - Manual (Page 4)

4
SECTION II
OPERATION INSTRUCTIONS AND PARTS LIST FOR TSQV VALVES
Part reference cited in this section can be identified
using Figures 1-3 (Section III) and the material list.
Periodic maintenance requirements for TSQV
valves may vary due to operating conditions
of the process. Factors such as operating
temperature and pressure, flowstream, solid
content, and valve cycles can greatly
influence valve performance and
maintenance requirements. Seal wear and
degradation is compensated by correctly
adjusting appropriate parts. For TSQV valves,
three possible leak paths occur; for each leak
path there exists a means of adjustment.
Leak paths are BONNET, STEM and LINE
(through). Each leak path and corresponding
adjustment shall be treated separately.
I. BONNET
Leakage due to thermal cycling (gradients) and
frequent high pressure cycling is stopped by
snugging the top cap fasteners (item 10) in a
"criss-cross" manner (1-3-2-4) per Fig. 3. This
adjustment is most effective when the valve is not
pressurized. It is important that the top cap
fasteners not be torqued above the level specified
in Tables 1a or 1b.
2. STEM
Leakage due to wear of the service packing is
stopped by tightening the packing adjuster
fasteners (item 8) in 1/2 turn increments. The
fasteners should be tightened evenly. The
packing adjuster fasteners should not be
tightened above the torque level specified in
Table 3 (pg 6). If possible, the valve should be
operated between adjustments to assure that
the plug stem will not be "frozen" due to
overloading the stem packing. If stem leakage
persists, or the packing adjuster fasteners
bottom out, the stem packing should be
replaced.
3. LINE (through)
Through leakage due to wear or damage to the
valve sleeve, or primary seal can be stopped by
tightening the plug adjuster fasteners (item 12)
in 1/4 turn increments. The fasteners should be
tightened evenly. If possible, the valve should be
operated between adjustments to assure that
the plug has not been forced into the sleeve
excessively, producing an unnecessary high
valve operating torque. Should the valve be
leaking excessively after numerous adjustments,
the sleeve will require replacement.
TSQV Assembly and Parts List