7.0 Operation, Inspection & Maintenance
7.1 Operation
a)
Flush the pipeline carefully when valve is mounted to remove all possible impurities.
Before flushing keep the valve fully open.
b)
Valve should be opened & closed slowly to avoid any hammering effect on the valve as
well as pipeline also.
c)
Valve should be used in accordance with the pressure & temperature chart.
7.2 Periodic Inspection and maintenance
a)
Annual inspection should be made to check up valve body, Disc, & Stem if worn or
pitted, substitute new one
b)
It is recommended to be replace seat , body gasket stem packing washers unless the parts
in good condition .
7.3 Lubrication
When the lube fitting are provided, valve should be lubricated periodically. Stem threads
must be brushed with the lubricants to avoid damage and excessive torque from developing
.Valve should never be operated without lubricated stem tread or yoke sleeves.
8.0 Disassembly
1)
For disassembly hold the valve properly.
2)
Loosen & remove handwheel lock nut.
3)
Remove handwheel.
4)
Loosen & remove the lock nut.
5)
Loosen and remove stem nut.
6)
Loosen and remove nuts from (gland packing)eye bolts.
7)
Remove the gland flange from the stem.( Gland flange assembly for handwheel)
8)
Remove the gland bush.
9)
loosen and remove nuts. (Body to bonnet)
10)
Lift bonnet along with stem & wedge.
11)
Remove the stem from bonnet along with the wedge.
12)
Remove the gasket from body.
Note :-
1)
Always use new gasket for assembly.
2)
Keep all parts clean and dry place.
3)
Replace damage parts for assembly.
4)
Make sure wedge lapped surface should not be damage while handling. (Caused
Leakage and keep on non metallic surface.)
9.0 Reassembly
1)
Hold valve body properly.
2)
Insert gasket in valve body.
3)
Hold bonnet properly.
4)
Insert the new gland packing in bonnet. ( If required)
5)
Insert stem along with the wedge in bonnet properly. ( Make sure gland packing should
not damage form stem threads )
6)
Insert the gland bush is the gland packing .
7)
Remove the hold from bonnet & put this bonnet along with the stem & wedge on valve
body. Make sure wedge should be properly insert in body with maintaining the position of
seat refer figure 2 .
8)
Bolt the bonnet properly with the help of stud and nut.(Stud &nut tighten slightly full
tighten done after total assembly.)
9)
Insert the gland flange. ( Gland flange assembly for handwheel)
10)
Insert and tighten the gland or eye bolts nuts properly.
11)
Insert stem nut properly as shown in figure 2.
12)
Insert the lock nut on stem nut and lock the stem nut.
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