The three-layer HDPE stripe winding process, with epoxy powder coating as bottom layer and binding adhesive as second layer, is the widely used technique in steel pipe anti-corrosion all over the world. The anti-corrosion steel pipe are applied in oil, gas and water supply pipelines.
Three-Layer structure of 3PE anti-corrosion pipe
The three-layer PE anti-corrosion structure includes fusion bonded epoxy-powder bottom layer, polymer adhesive middle layer and polyethylene outside layer. The epoxy powder is a kind of thermosetting nontoxic coating, forming the high molecular weight cross-linking structure coating after solidifying, featuring good chemical anti-corrosion and high mechanical properties. Function of epoxy layer is to form continuous coating and to provide the steel tube surface with good chemical resistance and cathodic disbanding resistance. The function of polymer adhesive is to agglutinate the epoxy layer and the polyethylene outside layer, which unites all three layers together. The polyethylene layer protects the pipe from abrasion, bump and water.
First layer is Fusion bonded epoxy layer (FBE> 100µm), the second layer is adhesive (AD) 170 ~ 250µm, and the third layer is polyethylene (PE) stripe 2.5 ~ 3.7mm.
3PE steel coating pipe has the features of high mechanical strength, excellent electrical insulation performance, Process accuracy and environmental friendliness.
The pipe coating line meets the requirements of producing the steel pipe with coating which meets international standards DIN30670-1991,CAN/ Z245.21-2010,ISO21809-1-2009 SY/T 0413-2002, GB/T23257-2009,GOST 9.602-2016, GOST R 51164-98, GOST31448, GOST31445![]()
The coating line mainly consists of the following units:
-steel pipe conveyor system
-shot/sand blasting system
-dust collector system
-pipe induction heating system
-epoxy powder spraying system
-PE&Adhesive coating system
-water cooling system
-pipe end cutting system
-hydraulic and pneumatic system
-testing system
-electronic control system
Qingdao Huashida Internal and External Epoxy Powder Anti-Corrosion Production Line
Seamless Steel Pipe Anti-Corrosion: A New Upgrade!
Simultaneous internal and external coating,
One-stop solution from rust removal, coating, and inspection to finished product delivery.
International standard certification, environmentally friendly and pollution-free
Equipped with a high-efficiency powder recovery system for green production
PLC intelligent control, simple operation, fully automated process
Robust protection, high efficiency and energy saving, customize your exclusive anti-corrosion pipes!
Technological process of 3LPE coating:
Pipe uploading→Shot blasting→Medium frequency induction heating→Epoxy powder spraying→Adhesive and polyethylene coating→Water cooling→Pipe end cutting back→Bevelling→Pipe unloading
The line can be customized to fit individual layout and application.
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Main Equipment List and specification
| No. | Name | Specification |
| A. Surface Cleaning Equipment | ||
| 1 | Steel pipe conveyor | Adjustable speed and angle, pipe uploading and unloading controlled by PLC |
| 2 | Shot blasting machine | |
| 3 | Cyclone dust collector | High efficient downwind cyclone dust removal |
| 4 | Impulse cartridge dust collector | |
| 5 | Centrifugal fan | |
| 6 | PLC control system | Automatic control of the line |
| B. Coating Equipment | ||
| 1 | Spiral pipe conveyor | Adjustable speed and angle |
| 2 | Induction heating machine | |
| 3 | Powder spraying device | Spraying thickness 80-800μm |
| 4 | Automatic feeder&dryer | |
| 5 | SJ-65/30 Extruder | |
| 6 | SJ-180/30 Extruder | |
| 7 | Adhesive extruder die mould | High quality die steel |
| 8 | PE sheet extruder die mold | High quality die stee |
| 9 | Adhesive/PE sheet coating device | Pressing roller with silicon coating and internal cooling |
| 10 | Environmental Protection Ventilation equipment | |
| 11 | Cooling Spray equipment | |
| C.Platform Equipment | ||
| 1 | Steel pipe platform | High quality |
| D.Groove Equipment | ||
| 1 | PE Beveling Machine | Steel brush disk, |
| 2 | Hydraulic Lifting and Turning Machinery | For lifting and turning the pipe |
| 3 | Hydraulic Equipment | |