How Stator Compression Deformation Affects the Stability of Single Screw Pumps

 How Stator Compression Deformation Affects the Stability of Single Screw Pumps

Single screw pumps are widely used for transferring:

High-viscosity fluids

Sludge and wastewater

Chemical liquids

Media containing particles

One major reason for their popularity is:

👉 stable and continuous flow delivery

However, in long-term operation, many systems gradually develop problems such as:

Unstable flow rate

Pressure fluctuation

Reduced conveying performance

In many cases, the root cause is not the motor or pipeline.

👉 The real issue is often stator compression deformation.

For more technical details, visit:

👉 https://www.scpv.cn/news/927.html

1. Why the Stator Is Critical in a Single Screw Pump

A single screw pump works through the interaction between:

A metallic rotor

An elastic rubber stator

Together, they form sealed cavities that continuously move fluid forward.

👉 The sealing effect between rotor and stator directly determines:

Flow stability

Pressure performance

Conveying efficiency

2. What Causes Stator Compression Deformation?

During long-term operation, the rubber stator is continuously exposed to:

Friction

Heat buildup

Mechanical compression

Over time, this can lead to:

Elastic fatigue

Permanent deformation

Loss of sealing performance

The risk becomes higher under these conditions:

High-speed operation

High-viscosity media

Continuous-duty operation

Dry running

3. How Deformation Affects Flow Stability

1️⃣ Increased Internal Leakage

When the stator loses proper compression:

👉 The sealing cavities become less effective.

This causes:

Backflow inside the pump

Reduced discharge pressure

Lower conveying efficiency

2️⃣ Unstable Flow Output

As cavity sealing becomes inconsistent:

👉 Flow delivery becomes unstable.

Common symptoms include:

Flow fluctuation

Pulsation increase

Irregular output

3️⃣ Reduced Conveying Capacity

A typical field complaint is:

👉 “The pump is still running, but it feels weaker.”

In reality:

Rotor rotation remains normal

But sealing efficiency drops

Resulting in:

Lower pressure

Reduced pumping performance

4️⃣ Increased Vibration and Noise

Uneven stator deformation may cause:

Rotor imbalance

Irregular mechanical loading

This can lead to:

Increased vibration

Abnormal noise

Higher mechanical stress

4. Why the Problem Is Often Ignored

Unlike sudden equipment failure:

👉 stator deformation usually happens gradually.

The performance decline is slow, so operators often assume:

👉 “It’s just normal aging.”

But in many industrial applications:

👉 The stator condition is actually the key factor affecting long-term stability.

5. Operating Conditions That Accelerate Deformation

Several common mistakes significantly shorten stator life:

❌ Running at excessive speed

Higher speed means:

More friction

More heat generation

❌ Dry running

Without fluid lubrication:

Rubber temperature rises rapidly

Damage accelerates

❌ Continuous high-pressure operation

Excessive discharge pressure:

Increases long-term compression stress

6. How to Reduce the Risk

Practical recommendations include:

Operate at reasonable speed

Avoid dry running

Maintain stable operating conditions

Select proper stator material for the medium

👉 The goal is to reduce heat and abnormal compression.

7. Conclusion

The stability of a single screw pump largely depends on:

👉 the sealing relationship between rotor and stator.

Once stator compression deformation occurs:

Sealing performance decreases

→ Internal leakage increases

→ Flow becomes unstable

→ Conveying performance declines

In real industrial applications, companies like Shanghai Shangcheng Pump & Valve have also found that:

👉 many “unstable pump performance” issues are actually caused by changes in stator condition—not motor failure.

More technical insights:

👉 https://www.scpv.cn/news/927.html