AB-7042
25
Table 1. Inspection items and details
Inspection item
Inspection interval
Inspection detail
Visual inspection
Semiannual
Fluid leakage from the gland and the flange face
Loosened
bolts
Valve and actuator damages
Operating status
Semiannual
Unstable open/close operation
Abnormal noise and vibration
Abnormal differential pressure across valve (Pvin-Pvout) in fully closed/open
position.
Routine inspection
Any time
Fluid leakage to the outside
Abnormal noise and vibration
Unstable open/close operation
Valve
hunting
Flow rate measuring
accuracy*
1
Any time (annual)
Measuring accuracy of differential pressure across valve:
Measure the valve inlet pressure and outlet pressure when they are equal and check
the values measured by the valve sensor. If difference of the values is
3 kPa, flow
rate measuring accuracy satisfies the factory preset accuracy.
Situation of inlet pressure equal to outlet pressure
No flow across the valve in open position
e.g, when supply pump is OFF, or when hand valves on the inflow and/or outflow
sides of the valve are/is fully closed.
Valve position detecting accuracy:
Select the position control*
2
, and check the position of the actuator pointer when
50 % position signal is input. If the pointer points out of 1 cm range from the 50 %
scale (the center of the lower setscrew of the terminal cover), product replacement is
required. See Fig. 36.
Notes:
1 Simplified inspection of flow rate measuring accuracy is illustrated above. For accurate inspection, a reference flow meter is required. Note
that you cannot field-calibrate or field-adjust flow rate measuring accuracy.
2 To select the position control, refer to
AB-7044 Instruction Manual of A
Standalone Model
.
Figure 36. Check of the valve position detecting accuracy
Disposal
Dispose of this product as industrial waste in accordance with your local regulations.
Do not reuse all or any part of the product.
1 cm 1 cm
Lower setscrew of
the terminal cover
Pointer