DERWENT INDUSTRIES

Derwent Resilient Seated Gripper Valves for PE, made in conjunction with AFC, are manufactured to AS/NZS 2638.2. The Gate Valves are applicable for water and waste water applications. Valves are available in both Anticlockwise and Clockwise configuration. Valves are supplied with Key Cap as standard,  ISO mounting plate for fitting, gearbox or actuators are available via special order.

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Features & Configurations:
 

• Material: Ductile Iron Body and Bonnet to AS 1831
   

• Wedge:  Ductile Iron AS 1831, fully encapsulated
  (Vulcanized) EPDM Rubber to AS1646 and AS681.1.
  The wedge is designed with abrasion resistant nylon
  guides which reduce the required opening 
  and closing torque through smooth operation
   

• Stem:  431 Stainless Steel to ASTM A276,
  providing excellent corrosion and strength,
  reducing moving parts
   

• Bolts:  316 Stainless Steel to ASTM A276, hot melt
  encapsulated for superior corrosion resistance in
  harsh environments
   

• Coating: Fusion Bonded Epoxy coated to  AS/NZS 4158
  provides the valve excellent corrosion protection

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Applications:

The Derwent Gripper Valves are for use in Potable Water, Waste Water, Fire, Irrigation, Water Circulation and Heating and Cooling applications and are suitable for both above and below ground installation.

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Technical Information:

Size range:

• DN 80 - 300

• Note: 125 and 180 currently available, other sizes mid-late 2022

    
Allowable Operating Pressure: 

• 1600 kPa; 1.6 Mpa

Maximum Test Pressure (Shell):  

• 2400 kPa, 2.4 Mpa

Maximum Temperature:  40 Deg C

Certification:    SAI Global  

Watermark Lic. No.    25890 
Standards Mark Lic. No. 25890

WSAA: PA 1511

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Installation:

1. Ensure Valve is correct size for the host pipe.

2. If using PE pipes with thin walls rated (> SDR 21) and low internal pressure, we recommend the use of a support liner.

3. Ensure pipe has a chamfered end prior to fitting to reduce the chance of seal damage and aid in inserting the pipe. (Refer to pipe manufacturers recommended chamfer size). Derwent recommendation.
   
   
   
   
   
   
    

4. Apply an approved pipe lubricant to the pipe end to assist with fitting.

5. Push the pipe end into the end of the socket.(Refer to insert depth on the back)

6. Tighten the locking ring bolts evenly around the fitting ensuring the ring is tight on the stop bushes.