3LPE pipe coating process

In today's demanding industrial environments, ensuring the longevity and reliability of pipelines is crucial. One of the most effective ways to protect pipelines from corrosion and mechanical damage is through the 3-Layer Polyethylene (3LPE) coating process. This advanced coating technology provides a robust shield, enhancing the durability and efficiency of pipelines, even under the most challenging conditions.

The 3LPE coating process is meticulously designed to offer superior protection. It involves multiple stages, each playing a vital role in creating a resilient coating that adheres perfectly to the pipeline. From induction preheating to epoxy and PE coating, each step is carefully executed to ensure optimal performance. With a combination of high-quality materials and state-of-the-art technology, the 3LPE coating process stands out as a premier choice for pipeline protection.

Let’s dive into the details of this innovative process and explore how it sets a new standard in pipeline coating technology.

1) Inbound Racks and Conveyors

Pipelines are loaded by this unit, which consists of inbound racks and conveyor systems driven by a hydraulic system. The main frame uses thick-walled rectangular structural steel pipe to ensure smooth transportation and meet the heavy-duty requirements. The retractable tube is automatically controlled by a PLC.

2) Induction Preheating

This unit heats the pipe for improved shot blasting performance using a medium-frequency induction heater. The pipe surface is heated to 50-60°C.

3) Shot Blasting

The shot blasting device removes dust, oil, and moisture from the pipeline surface, enhancing coating performance and longevity.

4) Epoxy Coating

A specially designed corona high-voltage electrostatic powder spray gun meets high-temperature requirements. The high-voltage electrostatic generator provides 100kV (DC) power, ensuring high speed and efficiency. The spray gun, made in Japan, features a modular design for easy maintenance. The stainless steel spray booth has a well-lit interior, and powder recovery uses cyclones and filter cartridges made of polyester fiber and microporous aluminum foil composite material. This material eliminates static electricity and can be cleaned with water.

5) Adhesive and PE Coating

Adhesive flows from the mold to coat the epoxy layer, enhancing the bond between the PE and epoxy layers. The PE and adhesive layers are laminated in-line.

6) Water Cooling

After coating with adhesive and PE layers, the pipe enters the cooling room for water-based cooling. The water circulates, and the conveying system automatically tilts during cooling to empty the water inside. The action of collecting and releasing tubes is also automatic.

7) Inspection Platform

The pipeline is now ready for inspection. The platform is used for quality inspection, diverting good and bad pipes to different areas.