Common Problems and Effective Solutions for Fully Welded Ball Valves

May 18, 2026

Fully welded ball valves are essential industrial valves used in oil, chemical, gas, and heating systems. Thanks to their compact design, high sealing performance, and easy operation, they are widely applied in industrial fluid control systems. However, even high-quality fully welded ball valves can experience common issues during long-term operation. This article discusses the most frequent problems and provides practical solutions to maintain optimal valve performance.

Valve Leakage and How to Fix It

Leakage in fully welded ball valves is a common issue that can disrupt system efficiency and pose safety risks. Major causes include:

  • Worn or damaged seals
  • Valve seat wear
  • Improper installation

Solutions for valve leakage:

  • Replace the Seal: Ensure new seals match the valve size and material, and follow the installation manual strictly.
  • Check Installation: Tighten all connections and clean sealing surfaces to prevent leakage.
  • Replace Valve Seat: Severe seat wear requires replacement to restore sealing performance.

Valve Stem Sticking: Causes and Solutions

A stuck valve stem can prevent smooth or complete operation. Common reasons include:

  • Accumulation of debris or sediment in the stem or guides
  • Insufficient lubrication

Solutions:

  • Clean Stem and Guides: Remove dirt and debris with appropriate solvents.
  • Lubricate: Apply a suitable industrial lubricant based on medium type and operating environment.
  • Replace Stem: Severely worn or deformed stems must be replaced to maintain operational efficiency.

Inflexible Valve Operation

Difficult operation or inability to fully open/close a valve can result from:

  • Bent or damaged valve stem
  • Stuck ball valve
  • Malfunctioning actuator or manual operating device

Solutions:

  • Inspect and Replace the Stem: Match material and size with the original valve.
  • Clean the Ball: Remove dirt and sediment to restore movement.
  • Check Operating Device: Repair or replace faulty parts to ensure smooth operation.

High Pressure Loss in Valves

Excessive pressure drop occurs when medium flow through the valve exceeds normal levels. Causes include:

  • Internal resistance in the valve body
  • Valve seat wear
  • Damaged ball valve

Solutions:

  • Clean Valve Body: Reduce flow resistance by removing debris.
  • Replace Seat or Ball: Restore normal valve function.
  • Optimize Valve Design: Select valves with low resistance structures considering medium properties and working pressure.

Poor Airtightness of Valves

Poor air tightness happens when a valve cannot prevent leakage in the closed state. Causes:

  • Worn sealing surfaces
  • Aging seals
  • Improper installation

Solutions:

  • Replace worn seals and clean sealing surfaces
  • Adjust installation alignment
  • Conduct regular airtightness tests to ensure compliance with industrial valve standards