Your Flow Control Valve Maintenance Checklist

We often talk about valve and cylinder performance. But like any part of a machine or system, flow control valves need to be inspected and maintained. So, how do you troubleshoot and do preventive maintenance on a flow control valve? 

Inspecting, confirming, and checking flow control valves for performance 

• Confirm that the nuts and bolts of the diaphragm are securely tightened. 
• Check that bonnet clamp bolts are tightened securely. 
• Inspect that the yoke clamp bolt is securely tightened. 
• Confirm that clamp bolts of any accessory device are tightened securely. 
• Check that the air connection to the actuator is securely tightened and there is no air leak. 
• The same inspection as above also applies to the stem connector to the actuator and valve stems. 
• Confirm that the actuator and valve stems are not warped or showing defective signs. 
• Check that the flow control valve smoothly operates within its full-scale range. 
• Inspect that the actuator spring is compressed correctly. 

Periodical maintenance 

• Check that there is no air leak between the diaphragm and diaphragm case. 
• Confirm that there is no process fluid leak from the flanges and bonnet. 
• Inspect that there is no air leak from the actuator air piping. 
• Check that the actuator and valve stems are not damaged in any way. 
• Confirm that the control valve does not have any abnormal vibration or sound. 
• If the control valve has a lubricator, periodically lubricate and tighten the gland packing section. 
• If the control valve has a manual handwheel, inspect that the pointer of the operation nut is in proper position with the AUTO position and that the handwheel is locked. 

Use the following testing methods for control valves after inspections 

• Visual examination of casting. 
• High-pressure closure test. 
• Low-pressure closure test. 
• Backseat test.  
• Shell test. 

Preventing cavitation 

For flow control valves, cavitation is reduced by increasing the distance between the trim parts and implosion of vapour bubbles. This can be done by providing flow aiding and by dropping the pressure by steps. 

MasterMac 2000 

With all of this, MasterMac 2000 is the exclusive distributor of flow control valve, pneumatic valves, and other valve and cylinder components, especially those manufactured by Univer and Mack since the 1980s. We even have high standard quality mixed or spool systems, as well air valves, compact valves, and pressure control valves. All of our brands are high quality and globally recognised such as Mack (Australian manufacturer), Univer, Tolomatic, American, Piab, and more. Contact us today for more information by calling us now on 07 3344 4711. You can also visit us MasterMac2000 at https://mastermac2000.com.au/suppliers/ and view all their product lines.