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Valve Disassembly Instructions

 

Before undertaking valve disassembly, it is recommended to gather the following tools to aid you during the process:
• Small & large adjustable wrenches
• Screwdriver set
• Machinist fine metal file
• Fine wire brush
• Bench vise
• Basic valve IO&M manual
• Hammer & dull cold chisel
• Heavy-duty ratchet & socket set
• Hexagonal wrench set
• 320 grit/fine Emery cloth
•  Appropriate technical bulletins for  

valve start-up procedures.

1.  Isolate the valve from line pressure and depressurize it to ensure safe working conditions. Disconnect any electrical  

connections if so equipped.

2.  Carefully remove Position Indicator or Limit Switches if equipped. Remove all tubing, fittings, and Control Pilots  

necessary to easily access and remove the cover. Remove cover nuts and washers.  

3.  Remove the cover. If cover is not free to be removed, loosen it by tapping upward along its outside edge with a dull cold chisel, pic-

tured above.  

a.  Large valves may require the installation of lifting “eye” bolts in order to facilitate cover removal; installation ports are provided on 

the cover for this purpose.

4.  Remove the Disc and Diaphragm Assembly from the valve body by lifting straight up. 

a.  Large diameter valves may require a lifting “eye” bolt to be installed in the valve stem accessory threads located on the very  

top of the valve stem.

5.  Before removing Stem Nut, examine stem threads for mineral build-up. Remove deposits with a fine wire brush. Extreme care should 

be taken not to damage the finish on stem guiding surfaces when disassembling. Avoid applying pipe wrenches to top or bottom 

stem guide surfaces.

VALVE COVER

BRASS BAR STOCK
(ANGLE UPWARD)

HAMMER

8          IOM-A-ACV-920-01_620-01   2115 

EDP# 1917052 

© 2021 Watts

IOM-A-ACV-920-01_620-01   2115 

EDP# 1917052 

© 2021 Watts         9

Summary of Contents for Ames 620GD

Page 1: ...2 Setting the Pressure Controls 3 Maintenance Schedule 6 Trouble Shooting Guide 6 Valve Disassembly Instructions 8 ACV Schematic 11 Local building or plumbing codes may require modifica tions to the...

Page 2: ...ude the optional opening speed control when used for Backpressure applications When the Model valve is located in line connecting two distribution zones the valve acts as a Pressure Sustaining Control...

Page 3: ...o 21 2 turns from full closed position STEP 2 To ensure proper operation any trapped air will need to be bled off the valve cover during startup If your ACV includes a bleed valve use a flat head scre...

Page 4: ...d close the up stream isolation valve until the inlet pressure drops to the desired setting STEP 7 Adjust the Sustaining Control screw IN clockwise until the inlet pressure begins to increase or OUT c...

Page 5: ...g IF INSTALLED Opening Speed Flow Control Adjustment The Opening speed flow control allows free flow into the cover and re stricted flow out of the cover of the main valve If recovery of pres sure is...

Page 6: ...specification sheets for approximate cover capacity A continuous flow of water from the open port indicates a damaged diaphragm or loose disc diaphragm assembly Disassemble valve and replace diaphragm...

Page 7: ...ly by partially opening from full closed position Improperly configured opening speed control if equipped Adjust opening speed control to verify functionality adjust as required Standard setting for o...

Page 8: ...move cover nuts and washers 3 Remove the cover If cover is not free to be removed loosen it by tapping upward along its outside edge with a dull cold chisel pic tured above a Large valves may require...

Page 9: ...rush or by using a Mineral Dissolving Solution Inspect parts for wear and replace if necessary 7 Inspect valve seat If seat is not damaged removal is not necessary Valve seats 6 and smaller are thread...

Page 10: ...ts in a crossing pattern to ensure even distribution Test the Disc and Diaphragm Assembly for smooth travel by following the Freedom of Movement Test procedure in previous section 11 Test the integrit...

Page 11: ...el 9 Stem Washer ASTM A276 304 Stainless Steel 10 Diaphragm Washer ASTM A536 65 45 12 Epoxy Coated Ductile Iron 11 Diaphragm Buna N Nitrile 12 Disc Retainer ASTM A536 65 45 12 Epoxy Coated Ductile Iro...

Page 12: ...resulting from labor charges delays vandalism negligence fouling caused by foreign material damage from adverse water conditions chemical or any other circumstances over which the Company has no cont...

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