Flowserve 50165 Nordstrom Figure - Manual (Page 28)

Nordstrom Figure 50165 and 50169 Dynamic Balance Iron Plug Valve FCD NVENIM2006-00 – 09/05
2
Problem: Operation difficulties
Cause 1: Insufficient sealant in the valve
Solution: The lack of sufficient sealant to adequately fill and pressurize the sealant system is the most
common problem associated with a valve being hard to operate. Inject the correct amount of sealant
into the valve and again check the operating torque of the valve.
Cause 2: Too tight of a plug adjustment
Solution: Loosen the plug adjustment.
1. Loosen the Plug Adjusting Screw 1 ⁄
8
turn.
2. Inject sealant into the valve.
3. The valve should now be operable.
Cause 3: Minor Stem corrosion (wrench operated valves)
Solution: Lubricate the Stem-to-Gland joint.
1. Remove the Retaining Ring and Stop Collar.
2. Remove the Weatherseal and inspect it for signs of damage. If the Weatherseal is damaged, replace
it. Check for corrosion on the stem or internal surface of the gland.
3. If corrosion exists, dam the area around the Stem-to-Gland joint with a heavy grease or Nordstrom
stick grade sealant.
4. Introduce penetrating oil into the Stem-to-Gland joint. Allow the penetrating oil to saturate for a
minimum of 24 hours. Periodically operate the valve.
5. If the valve becomes operable, clean the Stem-to-Gland joint of excess penetrating oil.
6. If penetrating oil does not free the valve, clean the Stem and inside surface of the Gland as
described in Operation Difficulties, Cause 4.
7. Coat the area under the Weatherseal with lithium base grease.
8. Replace the Weatherseal, Stop Collar, and Retaining Ring.
Cause 4: Severe Stem corrosion (wrench operated valves)
Solution: Remove corrosion from the Stem and interior surface of the Gland or Gland Retainer (gear
operated valves).
1. Remove the Retaining Ring and Stop Collar.
2. Remove the Weatherseal and inspect it for signs of damage. If the Weatherseal is damaged, replace
it. Check for corrosion on the Stem or internal surface of the Gland.
3. If corrosion exists, attempt to lubricate the Stem-to-Gland joint as described in Operation Difficul-
ties, Cause 3. If this does not work, continue with Step 4.
Remove line pressure from the valve before performing the following procedures.
4. Remove the Gland and Gland Bolts.
5. Remove internal corrosion from the Gland by scraping and/or #120 emery cloth.
6. Remove Stem corrosion by scraping and/or #120 emery cloth.