Common Problems and Solutions in Producing PVC Double-Wall Corrugated Pipes and Ribbed Pipes with One-Pack Lead Stabilizers

PVC double-wall corrugated pipes and ribbed pipes are widely used in drainage, sewerage, and infrastructure applications. 

However, during production, processors often encounter issues related to formulation design, plasticization, lubrication balance, and raw material quality. 

Below are some of the most common problems and practical solutions.

1. Irregular Corrugation on the Outer Wall

Irregular corrugation is usually caused by poor material flowability, insufficient plasticization, or the use of high-viscosity PVC resin.

To solve this problem:

-Adjust the formulation to improve melt flowability.

-Enhance the plasticization performance of the compound.

-Consider switching to a lower-viscosity PVC resin.

2. Excessive Dents on the Outer Wall

Dents on the outer wall are often associated with excessive impurities in raw materials or inadequate plasticization.

Recommended actions:

-Implement strict quality control for all raw materials and additives.

-Improve the plasticization capability of the formulation.

3. Pinholes on the Outer Wall

Outer wall pinholes generally result from poor material flowability, insufficient plasticization, or excessively high resin viscosity.

Possible solutions include:

-Increasing the flowability of the compound.

-Improving plasticization efficiency.

-Selecting a lower-viscosity PVC resin.

4. Pinholes on the Inner Wall

Inner wall pinholes are commonly caused by an improper balance between internal and external lubricants or by poor-quality raw materials.

To address this issue:

-Optimize the ratio of internal and external lubricants.

-Use qualified and consistent raw materials and additives.

5. Difficult Processing and Forming

Processing difficulties are usually related to excessive external lubrication, poor raw material quality, high moisture content, or excessive lubricant levels in the formulation.

Solutions:

-Reduce the dosage of external lubricants.

-Use high-quality raw materials and additives.

-Thoroughly dry the raw materials before processing.

-Lower the overall lubrication level in the formulation.

6. Rough or Foamed Pipe Surface

A rough or foamed pipe surface is often caused by excessive moisture or volatiles, poor thermal stability, or insufficient lubrication.

Recommended measures:

-Dry the materials thoroughly and reduce the use of low-melting-point lubricants.

-Replace the stabilizer or increase its dosage while removing impurities from the formulation.

-Increase the lubricant dosage appropriately.

7. Pipe Discoloration and Decomposition

Discoloration and thermal degradation generally indicate poor thermal stability, insufficient flowability, or poor-quality raw materials.

Corrective actions:

-Replace the stabilizer or increase its dosage.

-Improve material flowability.

-Select qualified raw materials.

8. Brittle Pipes

Pipe brittleness can be caused by impurities, insufficient plasticization due to excessive external lubrication, excessive filler loading, inadequate impact modifier dosage, or poor-quality raw materials.

Possible solutions:

-Remove impurities from the formulation.

-Adjust the formulation to improve plasticization.

-Reduce filler loading or improve filler coating quality.

-Increase the dosage of impact modifiers.

-Use high-quality raw materials and additives.

9. Uneven Rib Filling in Ribbed Pipes

Uneven rib filling is typically caused by excessive lubrication or insufficient melt pressure.

To improve rib filling:

-Reduce the lubricant dosage.

-Increase melt pressure appropriately.

In corrugated and ribbed pipe production, many processing issues can be minimized through proper formulation design, balanced lubrication, adequate plasticization, and the selection of a high-performance composite lead stabilizer system.

At Novista, we continue to work closely with pipe manufacturers worldwide to optimize formulations and improve processing efficiency and product quality.

What challenges have you encountered in PVC pipe production? 

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