Common malfunctions and their causes of general & automatic valves

Common malfunction and its causes of general valves

1. Causes & Maintenance Methods of Stuffing Box Leakage

Causes of Stuffing Box Leakage	Maintenance Methods
Incorrect Packing (Such as spinning the tube)	Pack correctly.
Deformation, Corrosion or Rust of the Valve Stem	Repair or change it for a new one.
Aging of the Stuffing	Change the stuffing.
Inappropriate Operation or Pushing too Hard	Operate stably.

2. Causes & Maintenance Methods of Valve Stem Malfunction

Causes of Valve Stem Malfunction	Maintenance Methods
Damage, Corrosion of Valve Stem	Replace the part.
Bent or Twisted Valve Stem	Do not pry handwheel with long handled tools when the valve is hard to open; Replace the valve stem.
Slant Valve-Stem Nut	Replace the part or the valve.
Rusty and Stuck Outdoor Valve	Enhance maintenance; Rotate the handwheel regularly.

3. Causes & Maintenance Methods of Leak Seal

Causes of Leak Seal	Maintenance Methods
Abrasion of Sealing Surface, Minor Corrosion	Regularly grind it.
Improper Closing, Bad Connection with Sealing Surface	Slowly open and close it a couple of times.
Bent or Twisted Valve Stem, Sealing Surfaces not Focusing on the Center Line	Repair or replace.
Impurities in Valve Opening	Open the valve, clean the impurities, and then slowly turn it off; Install a filter if necessary.
Loose Connection among Seal Ring, Valve Body and Valve Clack	Repair.
Loose Connection Between Valve Clack and Valve Stem	Repair or replace the part.

4. Causes & Maintenance Methods of Other Malfunctions

Other Malfunctions	Causes	Maintenance Methods
Gasket Leak	Inadaptable Gasket, Losing Efficacy Because of the Affection of Media in Daily Used	Change to an adaptable one.
Cracked Valve	Damage from Cryogenic Temperature, Pushing too Hard	Preserve heat, install evenly.
Broken Handwheel	High Impact, Pry with Long Handled Tools, Attrited Chamfer	Prevent hitting, evenly open in the correct direction, rasp the square hole or replace the handwheel.
Cracked Gland	Unbalanced Force in Tightening the Gland	Symmetrically screw down the nut.
Malfunctioned Disc	Rusty Wedge Gate Losing Sealability, Broken Upper Wedge of the Double Disc	Regularly grind it or replace to carbon steel wedge.

Common malfunctions & causes of automatic valves

1. Common malfunctions, causes, preventive measures and maintenance methods of check valves

Common Malfunctions of Check Valve	Causes	Maintenance Methods
Medium Backflow	Leaky Sealing Surface Between Valve Core and Valve Body	Grind the sealing surface.
Medium Backflow	Impurities Between Valve Core and Valve Body	Remove the impurities.
Unopenable Valve Core	Sticky Furr on Sealing Surface	Clear away the furr.
Unopenable Valve Core	Rusty Spindle	Polish the spindle.
Frangibility of Valve Clack	Unbalanced Force from Pressure	Use valve clack with ductile materials.

2. Common malfunctions, causes, preventive measures and maintenance methods of steam trap valves

Common Malfunctions of Steam Trap	Causes	Maintenance Methods
Unable to Drain	Low Pressure of Steam	Adjust pressure.
	Steam and Condensate Water not Entering the Steam Trap	Check if the valve is closed or clogged.
	Light Weight of Float	Add suitable weight or replace it.
	Valve Stem Stuck with Casing Pipe	Repair or Replace.
	Clogging	Clean it, install a filter.
	Broken Isothermal Valve Core	Replace it.
Steam Leakage	Worn Valve Core and Body	Grind the sealing surface.
	Drain Hole Unable to Close Automatically	Check if there's dirt clogging.
	Small Volume of Float	Increase its volume.
Falling Temperature	Condensate Water Remaining	Replace the steam trap.
Falling Temperature	Condensate Water Remaining	Install a steam trap.

3. Common malfunctions, causes, preventive measures and maintenance methods of relief valves

Common Malfunctions of Relief Valve	Causes	Maintenance Methods
Unstable Pressure	Impulse-type: Unsuitable Valve Diameter, High Pressure Difference	Change to a proper relief valve.
Unstable Pressure	Spring-loaded Type: Unfitted Regulating Spring	Change to a proper regulating spring.
Valve Clogging	Impurities	Remove the impurities, install a filter in front of the valve.
Valve Clogging	Rusty Plunger	Repair the plunger
Useless Valve	Rusty Plunger	Repair the plunger
	Broken Spring (under the valve clack of the main valve)	Replace the spring.
	Valve Handle (impulse-type) Stuck in the Closed Position	Overhaul.
	Impurities or Severe Corrosion Between the Valve Clack and Valve Body	Remove the impurities, regularly grind the sealing surface.
	Diaphragm Losing Efficacy	Replace it.
Unadjustable Pressure	Malfunction of Regulating Spring	Replace.
	Leakage on the Cap, Unstable Pressure	Overhaul, replace the gasket.
	Worn or Corroded Plunger, Air Cylinder	Overhaul the air cylinder, change the piston ring.
	Condensate Water	Loosen the plug, empty the condensate water.

4. Common malfunctions, causes, preventive measures and maintenance methods of safety valves

Common Malfunctions of Safety valve	Causes	Maintenance Methods
Leaking Sealing Surface	Impurities or Worn Sealing Surface Between the Valve Core and Body	Remove the impurities or grind the surface.
Leaking Sealing Surface	Obliquitous Center Line of the Valve Rod	Rectify the center line.
Unopenable Valve even with Exceeded Working Pressure	Stuck Lever or Rusty Dowel	Overhaul
	Moved Hammer (lever-type)	Adjust the position of the hammer.
	Distortion or Losing Efficacy of the Spring due to High Temperature	Replace the Spring
	The Valve Core Pasting on the Valve Body	Regularly test exhaust emissions.
Valve Opening Without Sufficient Working Pressure	The Lever Hammer Moving Inward	Adjust its position.
Valve Opening Without Sufficient Working Pressure	Not Springy Enough (spring-type)	Tighten up or replace the spring.
Unable to Close Automatically	Obliquitous Lever (lever-type)	Repair.
	Curve Spring (spring-type)	Adjust the spring.
	Obliquitous Valve Core or Valve Rod	Adjust.

Baltic Valve