HLA
– Double acting- hydraulic linear actuator
Use and maintenance manual
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Pag. 12
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3) -Disassemble the two halves of actuator pedestal shell joint (item 8) by
unscrewing the retaining screws (item 4 ),therefore disassemble the
valve stem joint (item 7).
4) -Lift the actuator by utilizing the proper lifting eyelets, and unscrew the
nuts and the stud bolts from the actuator pedestal.
5) -Assemble the actuator onto the valve, and arrange it in its correct
vertical position proper to connection between valve stem and actuator
cylinder rod.
6) -Screw the valve stem joint (item 7) on valve stem up to reach the proper
position which allow the reassembly of the two halves of shell joint (item
8), tighten the joint fastening screws (item 4).
7) -Screw the stud bolts (item 1) into the actuator pedestal flange, and
screw the nuts on the stud bolts.
8) -Tighten according to the nut (item 2) size torque requirements.
To operate refer to following table:
Table 1:
nuts tightening torque
Threading
Tightening
torque (Nm)
M8
20
M10
40
M12
70
M14
110
M16
160
M20
320
M22
420
M24
550
M27
800
M30
1100
M33
1400
M36
1700
The screwing values in Table 1 were calculated considering the
materials ASTM A320 L7 for screws or tie rods and ASTM A194
gr.2H for the nuts.
