AVK UK, 8 Rushmills, Northampton, England, UK, NN4 7YB, T: + 44 (0) 1604 601188. [email protected] www.avkuk.co.uk
COPYRIGHT©AVK GROUP A/S 2013
O&M 21.10.21
The designs, materials and specifications shown are subject to change without notice due to our continuing programme of product development.
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3. INSTALLATION
1. Evacuate area around pipe leaving sufficient clearance to safely assemble the under pressure tee.
2. Thoroughly clean area of pipe where fitting is to be fitted, ensuring that all loose particles are removed.
3. Measure and check diameter of pipe against sealing range of fitting.
4. Check that pressure rating of fitting is compatible with working pressure of main.
5. Check that both the medium within the pipe and its operating temperature is suitable for the fitting to be assembled.
6. Split fitting into two halves by removing nuts.
DO NOT REMOVE BOLTS
DO NOT REMOVE SEAL ASSEMBLIES FROM EACH HALF
7. Lubricate area of pipe where fitting is to be installed using a WRAS approved silicone based lubricant for water, and mineral oil based lubricant for gas.
Lubricate the seals of the fitting including where the seals meet each other. This is extremely important to ensure bolt torque is effectively transferred into
rubber compression.
8. Offer fitting half complete with bolts to underside of pipe and support.
9. Locate top half of fitting over bolts and loosely fit nuts to bolts.
10. If necessary rotate fitting carefully to the required position.
11. Finger tighten the nuts ensuring the gap between the half bodies are even on each side of the fitting.
Tighten each nut evenly to a maximum of ½ turn at a time diagonally across the fitting until the recommended torque is reached. It is very important to tighten
the nuts gradually and evenly to ensure the seal is gradually compressed and given chance to move into position.
Use torque wrench
Complete one final pass in a clockwise direction to check recommended torque is achieved.
Ensure fitting is level across pipe diameter during installation
Ensure fitting is level along axis of pipe during installation
Ensure recommended bolt torque is applied to all bolts
It is advisable to recheck the torque settings 10 minutes after initial assembly in case of seal and bolt relaxation.
4. SEALING DIAMETERS & RECOMMENDED BOLT TOQUES
Note: Should the fitting be used in an aggressive (e.g. salt laden) environment please ensure there is sufficient secondary corrosion protection applied before
backfilling.
257/30 - Water
257/31 - Gas
Sealing Diameters
Recommended
Sealing Diameters
Recommended
Nom Size
MIN
MAX
Bolt Torque
MIN
MAX
Bolt Torque
Inches/mm
mm
mm
Nm
mm
mm
Nm
3"/80
85.4
114.0
68
n/a
n/a
n/a
4"/100
111.8
139.0
68
118.8
129.4
68
6"/150
165.2
195.5
100
165.2
184.8
100
8"/200
215.9
239.7
168
215.9
239.7
168
10"/250
269.2
293.5
190
269.2
293.5
190
12"/300
319.9
341.3
190
319.9
341.3
190
