Common Butterfly Valve Problems and How to Avoid

April 30, 2026
0 comments

In many projects, butterfly valves are widely used in water treatment, HVAC, and general piping systems due to their relatively simple design and ease of installation and maintenance. However, after a period of operation, issues can still arise—such as leakage, increased operating torque, or even premature failure.

In most cases, these problems are not random. They often originate from improper selection or a mismatch between the valve design and actual working conditions. Based on practical experience, many of these issues can be anticipated and avoided. The following sections outline some common problems seen in real applications, along with practical guidance for valve selection.

1. Sealing Leakage

Sealing leakage is the most common issue, typically appearing as incomplete shut-off or continuous minor leakage during operation.

In practice, it usually comes from three main factors:

Aging of sealing materials
Soft sealing materials gradually age or harden over time, especially under temperature fluctuations or in chlorinated water environments.
Seat wear
When the medium contains sand or other particles, the seat is subject to continuous wear.
Installation or stress-related issues
Installation misalignment or pipeline stress can affect the contact between the disc and the seat, leading to poor sealing.

Many of these issues can be addressed at the selection stage:

For general water or HVAC systems, EPDM is a common choice due to its good elasticity and cost-effectiveness
For corrosive media or fluctuating temperatures, PTFE is recommended
In applications with poor water quality or high levels of impurities, a fully vulcanized seat is generally a better option

2. Difficult Operation / High Torque

In some projects, butterfly valves operate smoothly at the beginning, but over time, opening and closing becomes increasingly difficult, sometimes even leading to sticking or jamming.
Common causes include:

Corrosion of the stem or bushings
Scale buildup or accumulation of debris inside the valve
Over-tightened packing
Insufficient torque allowance during selection

In essence, these issues are caused by increased operating resistance, without sufficient margin considered at the selection stage.

From a practical standpoint, many of these problems can be avoided early on:

In water systems, it is recommended to use corrosion-resistant stem materials, such as stainless steel
For systems with poor water quality, consider regular maintenance or allow additional operating margin during selection
When selecting actuators, ensure adequate torque margin is included
For large-diameter butterfly valves, it is advisable to use a gearbox or properly sized actuator

Image source: istockphoto

3. Stem Damage

Stem damage is not the most common issue, but once it occurs, it can significantly affect the overall operation of the valve.
It is typically related to the following factors:

Insufficient material strength
Fatigue caused by frequent operation over time
Excessive actuator torque
Uneven stress due to inadequate machining accuracy

From an engineering perspective, this type of issue is closely linked to load distribution and design.
Higher specifications are recommended in the following cases:

High-frequency operation
Large-diameter valves
Automated systems

Both the material selection and machining accuracy of the stem play a critical role in long-term reliability.

4. Seat Deformation or Failure

The seat is a critical component for sealing in a butterfly valve. Once it becomes deformed or damaged, leakage is usually unavoidable, directly affecting normal operation.

This issue is more likely to occur in systems with long service periods or fluctuating operating conditions. Common causes include:

Temperature fluctuations
Repeated temperature changes can cause rubber seats to expand and contract, which may lead to deformation over time.
Frequent pressure variations
Continuous pressure fluctuations can subject the seat to repeated compression, resulting in loosening or structural deformation.
Insufficient seat stability
In some designs, especially insert-type seats, long-term use may lead to loosening or misalignment, affecting sealing performance.
Media conditions
Corrosive media or fluids containing particles can accelerate seat aging and wear.

In practice, different seat designs perform quite differently over time.

For applications requiring higher reliability, a fully vulcanized seat is generally recommended to minimize the risk of loosening or deformation.

Image source: istockphoto

5. Corrosion Issues

In certain applications, corrosion is a key factor affecting the service life of butterfly valves—particularly in chemical processes, seawater systems, or environments with corrosive media.

Typical signs include rusting of the valve body, pitting on the disc, and in severe cases, stem seizure or sealing failure.

In most cases, these issues are directly related to material selection:

General water systems: ductile iron with epoxy coating
Seawater applications: 316 stainless steel, duplex stainless steel, or aluminum bronze
Corrosive media: PTFE-lined designs can be considered

From practical experience, most corrosion-related problems are not due to product quality, but rather a mismatch between materials and actual operating conditions.

6. Actuator Problems

In automated systems, some issues that appear to be “valve failures” are often caused by the actuator or control system.

Typical symptoms include failure to open or close properly, slow response, or inaccurate positioning.

Common causes:

Improper torque matching
Unstable air supply or power supply
Control signal issues

In practice, the valve and actuator should be treated as an integrated system during selection, rather than being considered separately.

butterfly valve

From an engineering perspective, most issues encountered with butterfly valves in operation are related to selection and application mismatch, rather than inherent product quality.

If, at the early stage of a project, materials, structure, and configuration are properly selected based on factors such as medium, water quality, temperature, and operating conditions, it can significantly reduce maintenance requirements and improve overall system reliability.

Union Valve focuses on butterfly valve applications in water treatment, HVAC, and various industrial systems. We provide practical selection support based on different working conditions. If you have a specific project requirement, feel free to reach out for further discussion.