3PE Steel Pipe Coating Line for DN114-820mm, Medium-Small Diameter Anti-Corrosion Production Equipment

Qingdao Huashida 3PE Steel Pipe Coating Line for DN114-820mm is a professional anti-corrosion coating system designed for DN114mm - DN820mm (max DN1020mm) steel pipes. This line features versatile medium-small diameter range, spiral wrapping for uniform coating, quick diameter changeover, delivering reliable coating quality for oil & gas field gathering networks, urban gas transmission pipelines, municipal water distribution mains. With 160kW PE extruder and 500kW intermediate frequency heating, this system is optimized for the Middle East, Southeast Asia, Africa, urban infrastructure projects market. Backed by over 20 years of manufacturing experience since 2003, with 58 invention patents, and 50+ successful installations worldwide, Huashida ensures stable operation, low maintenance cost, and coating quality that meets international standards.

 

 

1. Wide diameter coverage of DN114mm - DN820mm (max DN1020mm) in a single production line, reducing equipment investment for mixed-size pipe mills

2. Spiral wrapping coating technology ensures uniform PE layer thickness and excellent adhesion for DN114mm - DN820mm (max DN1020mm) pipes

3. Compact O-type or side-wrap coating head design minimizes floor space requirement

4. Quick diameter changeover via PLC recipe storage, reducing setup time between production batches

5. 38CrMoAlA nitrided screw with >HV740 hardness delivers 30% higher output at same power consumption

The anti-corrosion coating processing line includes:
-steel pipe transmission system
-Internal and external shot blasting system
-dust collection system
-pipe heating system
-electrostatic spraying system
-PE coating system
-water cooling system
-end cutting system
-hydraulic and pneumatic system
-testing system
-electronic control system

Coating Process: 3PE spiral wrapping coating (FBE + AD adhesive + PE), side-wrap extruder

Standard 3PE Process Sequence:

Pipe Loading -> External Shot Blasting (Sa 2.5) -> Pipe Internal Air Purging
-> Pipe End Masking -> Intermediate Frequency Heating (~200deg C)
-> FBE Epoxy Powder Spraying -> AD Adhesive Extrusion & Wrapping
-> PE Extrusion & Wrapping -> Water Spray Cooling -> Joint Cutting
-> PE End Beveling -> Holiday Detection -> Finished Pipe Unloading

3. Key Configuration

At the heart of this DN114mm - DN820mm (max DN1020mm) coating line are two precision extruders: SJ-65/30 single screw extruder, 37kW, max output 100 kg/h for the adhesive layer and SJ-120/30 high-efficiency single screw extruder, 160kW, max output 600 kg/h for the polyethylene top layer. The screws are manufactured from 38CrMoAlA nitrided steel, with nitriding depth of 0.4-0.7mm and hardness above HV740, ensuring long service life and stable plasticization.

Supporting the extruders is 500kW intermediate frequency heating, C-type coil, pure water cooling, heating pipes to approximately 200deg C with C-type coil and pure water cooling system. Surface preparation is handled by external shot blasting machine, 90kw, sa 2.5 grade, anchor profile 50-90um, delivering Sa 2.5 cleaning grade with 50-90um anchor profile. The FBE powder application station features multi-gun electrostatic spray with (n+1)x2 redundant design, recovering over 95% of powder through an integrated reclaim system.

The entire line is orchestrated by internationally recognized PLC with 10-inch industrial-grade HMI touchscreen, with VFD from internationally recognized brands and industrial-grade control components. Pipe diameter range covers DN114mm - DN820mm (max DN1020mm) with standard length of 6-15 meters. Post-coating cooling uses water spray quench system (<=20deg C, >=0.3MPa, 26-30 m3/h), followed by rotary peeler knife end beveling (~40 sec/pipe with kraft paper masking). Quality verification includes high-voltage holiday detection and coating thickness measurement. Staffing requirement is 4-5 operators, with minimum workshop height of 9 meters for large diameter configurations.
 

1. Pipe diameter: 114-820mm
2. Processing capacity: ≥250m²/h
3. Cleaning level: ≥Sa2.5
4. Materials for production: epoxy powder, adhesive, polyethylene

Why Choose Qingdao Huashida

What sets Qingdao Huashida apart is not just equipment manufacturing - it is field-proven design philosophy. Unlike manufacturers who only build machines without practical production knowledge, Huashida operates its own coating factory in China. Every design improvement is refined through real production experience, ensuring that machines are battle-tested in actual coating operations before reaching customers. This hands-on approach, combined with 58 invention patents and 38 utility model patents, results in equipment that solves real production problems rather than creating new ones.

Established in 2003 and headquartered in a 33,000 m2 industrial park in Qingdao, the company employs over 100 professionals including 4 senior engineers and 15 mechanical technicians. Core technology comes from Germany, with R&D partnerships with Beijing University of Chemical Technology and other leading institutions. For oil & gas field gathering networks, urban gas transmission pipelines, municipal water distribution mains, this practical heritage means equipment that starts production quickly, runs stably, and requires minimal intervention - qualities that directly translate to higher profitability for coating operators.