Ten Common Misconceptions in Valve Installation – Frequent Errors Easily Made
With the rapid advancement of technology and innovation, valuable information for industry professionals is often overlooked nowadays. While shortcuts may satisfy short-term budget constraints, they reflect insufficient experience and a lack of comprehensive understanding of long-term system operability. Drawing from practical experience, the following list (in no particular order) outlines ten easily neglected installation pitfalls:
1. Overlong Bolts
For valve bolts, only one or two screw threads should extend past the nut. This minimizes risks of damage and corrosion.
Why purchase bolts longer than required? Excessively long bolts are usually used because personnel fail to calculate the proper length or disregard the final outcome. This constitutes sloppy engineering.
2. Control Valves Not Equipped with Independent Isolation
Although isolation valves occupy valuable space, they are critical to allow maintenance work on the valves when needed. If space is limited and gate valves are deemed too lengthy, butterfly valves shall be installed at minimum, as they occupy almost no space. Always bear in mind that proper working space facilitates on-site maintenance and operation, enabling technicians to complete maintenance tasks more efficiently.
3. No Pressure Gauges or Instrument Connection Ports Installed
Some operators rely on portable calibration testers. While facilities generally provide field staff with interfaces for connecting testing equipment, some assemblies lack built-in accessory ports. Though not mandatory, proper design should enable direct observation of actual valve pressure. Even with SCADA (Supervisory Control and Data Acquisition) and telemetry systems, personnel will occasionally stand beside valves to check on-site pressure readings, which brings great convenience.
4. Insufficient Installation Clearance
If installing a valve station involves cumbersome work such as concrete excavation, do not attempt to cut costs by minimizing installation space. Basic maintenance will become extremely difficult in the future.
Another important reminder: tools can be lengthy, so reserved clearance must be provided to loosen bolts. Extra space should also be reserved for adding equipment at a later stage.
5. Failure to Consider Future Disassembly
Most installers recognize that all components cannot be rigidly connected inside a concrete chamber without detachable connections for future removal. If every part is fastened tightly without clearance, separation will become nearly impossible. Slip couplings, flanged joints or threaded pipe connections are essential.
Components may require removal sometime in the future. While this is often ignored by installation contractors, it should be a key concern for asset owners and design engineers.
6. Horizontal Installation of Concentric Reducers
This detail may seem trivial but deserves attention. Eccentric reducers can be installed horizontally, whereas concentric reducers are intended for vertical piping.
If horizontal installation of a reducer is required for certain applications, an eccentric reducer shall be adopted. This mistake often arises from cost considerations, since concentric reducers are cheaper.
7. Valve Chambers Without Drainage Provisions
All enclosures are prone to water accumulation. Even during valve commissioning, water will drip onto the floor as air is vented from the valve bonnet. Flooded valve chambers are commonly seen in industrial sites, and such incidents are avoidable (unless the entire area is inundated, which creates far more serious issues).
If drain pipes cannot be installed, simple drain pumps may be deployed if power supply is available. Where power is unavailable, float valves with ejectors can effectively keep the chamber dry.
8. Lack of Air Venting Arrangements
When pressure drops, entrained air separates from the fluid and accumulates within pipelines, triggering faults downstream of the valve. A simple bleed valve removes trapped air and prevents subsequent downstream malfunctions.
Installing bleed valves upstream of control valves is also effective, as air within pilot lines may cause operational instability. It is better to eliminate air before it reaches the control valve.
9. Spare Tapping Points
This may appear minor, yet spare tapping points upstream and downstream of control valves inside chambers are always beneficial. This arrangement facilitates future maintenance work, including hose connection, remote sensing modification for control valves, or mounting pressure transmitters for SCADA systems.
The small additional cost of adding fittings during the design phase greatly improves system serviceability in the long run. Without reserved ports, maintenance tasks will become difficult, as paint coverage may obscure nameplates and hinder adjustment operations.
10. Closing Remarks
Doing work correctly always delivers long-term benefits, while shortcuts usually lead to endless troubles.
Some people may regard these ten points as overly meticulous, but a wise senior mentor once told me: "Chew the meat, spit out the bones."
1. Overlong Bolts
For valve bolts, only one or two screw threads should extend past the nut. This minimizes risks of damage and corrosion.
Why purchase bolts longer than required? Excessively long bolts are usually used because personnel fail to calculate the proper length or disregard the final outcome. This constitutes sloppy engineering.
2. Control Valves Not Equipped with Independent Isolation
Although isolation valves occupy valuable space, they are critical to allow maintenance work on the valves when needed. If space is limited and gate valves are deemed too lengthy, butterfly valves shall be installed at minimum, as they occupy almost no space. Always bear in mind that proper working space facilitates on-site maintenance and operation, enabling technicians to complete maintenance tasks more efficiently.
3. No Pressure Gauges or Instrument Connection Ports Installed
Some operators rely on portable calibration testers. While facilities generally provide field staff with interfaces for connecting testing equipment, some assemblies lack built-in accessory ports. Though not mandatory, proper design should enable direct observation of actual valve pressure. Even with SCADA (Supervisory Control and Data Acquisition) and telemetry systems, personnel will occasionally stand beside valves to check on-site pressure readings, which brings great convenience.
4. Insufficient Installation Clearance
If installing a valve station involves cumbersome work such as concrete excavation, do not attempt to cut costs by minimizing installation space. Basic maintenance will become extremely difficult in the future.
Another important reminder: tools can be lengthy, so reserved clearance must be provided to loosen bolts. Extra space should also be reserved for adding equipment at a later stage.
5. Failure to Consider Future Disassembly
Most installers recognize that all components cannot be rigidly connected inside a concrete chamber without detachable connections for future removal. If every part is fastened tightly without clearance, separation will become nearly impossible. Slip couplings, flanged joints or threaded pipe connections are essential.
Components may require removal sometime in the future. While this is often ignored by installation contractors, it should be a key concern for asset owners and design engineers.
6. Horizontal Installation of Concentric Reducers
This detail may seem trivial but deserves attention. Eccentric reducers can be installed horizontally, whereas concentric reducers are intended for vertical piping.
If horizontal installation of a reducer is required for certain applications, an eccentric reducer shall be adopted. This mistake often arises from cost considerations, since concentric reducers are cheaper.
7. Valve Chambers Without Drainage Provisions
All enclosures are prone to water accumulation. Even during valve commissioning, water will drip onto the floor as air is vented from the valve bonnet. Flooded valve chambers are commonly seen in industrial sites, and such incidents are avoidable (unless the entire area is inundated, which creates far more serious issues).
If drain pipes cannot be installed, simple drain pumps may be deployed if power supply is available. Where power is unavailable, float valves with ejectors can effectively keep the chamber dry.
8. Lack of Air Venting Arrangements
When pressure drops, entrained air separates from the fluid and accumulates within pipelines, triggering faults downstream of the valve. A simple bleed valve removes trapped air and prevents subsequent downstream malfunctions.
Installing bleed valves upstream of control valves is also effective, as air within pilot lines may cause operational instability. It is better to eliminate air before it reaches the control valve.
9. Spare Tapping Points
This may appear minor, yet spare tapping points upstream and downstream of control valves inside chambers are always beneficial. This arrangement facilitates future maintenance work, including hose connection, remote sensing modification for control valves, or mounting pressure transmitters for SCADA systems.
The small additional cost of adding fittings during the design phase greatly improves system serviceability in the long run. Without reserved ports, maintenance tasks will become difficult, as paint coverage may obscure nameplates and hinder adjustment operations.
10. Closing Remarks
Doing work correctly always delivers long-term benefits, while shortcuts usually lead to endless troubles.
Some people may regard these ten points as overly meticulous, but a wise senior mentor once told me: "Chew the meat, spit out the bones."
