3LPE Coating Line for 20”-100” (DN508-2540mm) Large Diameter Steel Pipe, Heavy-Duty Anti-Corrosion System

Qingdao Huashida 3LPE Coating Line for 20”-100” (DN508-2540mm) Large Diameter Steel Pipe is a professional anti-corrosion coating system designed for 20” - 100” (DN508mm - DN2540mm) steel pipes. This line features proven configuration: sj-120/38 pe extruder (400kw, 1200kg/h), 1500kw if heating per unit, heavy-duty structure for large pipes, multiple successful installations, delivering reliable coating quality for large-diameter oil & gas transmission, major water transfer projects, coastal infrastructure, large-scale municipal pipelines. With 400kW

PE extruder and 1000kW intermediate frequency heating, this system is optimized for the UAE, Saudi Arabia, South Africa, China, India, large-diameter pipeline EPC contractors 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 20” - 100” (DN508mm - DN2540mm) 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 20” - 100” (DN508mm - DN2540mm) pipes

3. Heavy-duty spiral conveyor with individual wheel drive handles large-diameter heavy pipes stably

4. Multi-zone intermediate frequency heating ensures uniform temperature across large pipe circumference

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

The anti-corrosion coating processing line includes:

Coating Process: 3LPE (3-Layer Polyethylene) spiral wrapping coating

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

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

This 20” - 100” (DN508mm - DN2540mm) production line features 1000kW intermediate frequency heating, C-type coil, pure water cooling as its thermal core, precisely heating steel pipes to approximately 200deg C for optimal FBE powder curing. The heating system incorporates C-type coils with pure water cooling and low-pressure protection (supply pressure >0.2MPa).

Process intelligence is delivered through internationally recognized PLC with 10-inch industrial-grade HMI, enabling recipe storage for one-click diameter changeover across 20” - 100” (DN508mm - DN2540mm) range. Variable frequency drives from internationally recognized brands ensure precise speed control, with industrial-grade electrical components throughout. Surface preparation uses external shot blasting machine, 2x37kw blast wheels, 350kg/minx2, sa 2.5 grade, achieving Sa 2.5 grade (ISO 8501-1) with 50-90um anchor profile depth. Coating application employs SJ-90/30 single screw extruder, 55kW (adhesive) and SJ-120/38 single screw PE extruder, 400kW, max output 1200 kg/h (polyethylene), both equipped with 38CrMoAlA nitrided screws (0.4-0.7mm nitriding depth, >HV740 hardness).

The FBE station uses multi-gun electrostatic spray with (n+1)x2 redundancy and >95% powder recovery. Pipe length capability is 6-15 meters (12m standard). Cooling is achieved through water spray quench (<=20deg C, >=0.3MPa, 26-30 m3/h), with end beveling via rotary peeler knife (~40 sec/pipe). Final quality control includes high-voltage holiday detection and thickness measurement. The line operates with 4-5 personnel and requires minimum 9-meter workshop height for large diameter models.

Applications

This coating line is specifically suited for:

• Large-diameter oil & gas transmission, major water transfer projects, coastal infrastructure, large-scale municipal pipelines

• Oil & gas transmission and distribution pipelines

• Municipal water supply and sewage pipelines

• Chemical plant process piping

• Mining and slurry transport pipelines

Target Market: UAE, Saudi Arabia, South Africa, China, India, large-diameter pipeline EPC contractors

Export Countries: Russia, UAE, Saudi Arabia, Iran, Uzbekistan, Kazakhstan, Nigeria, South Africa, India, Thailand

Standards Compliance

This equipment is designed and manufactured in compliance with:

• GB/T 23257-2017

• DIN 30670

• ISO 21809-1

• ISO 8501-1 (Sa 2.5)

All coating parameters (FBE >=150um, AD >=170um, PE 3.3-4.2mm per GB/T 23257-2017) can be configured to meet project-specific inspection and test plans (ITP). Coating thickness calculated per formula: coating weight = surface area x thickness x material density.

Why Choose Qingdao Huashida

Qingdao Huashida’s large-diameter capability is industry-leading, with proven projects up to DN6600mm domestically and DN2540mm overseas. This extensive track record in large-diameter pipeline coating demonstrates the company’s ability to handle the most challenging pipeline coating requirements, including the 20” - 100” (DN508mm - DN2540mm) range of this product line.

Established in 2003 and operating from a 33,000 m2 facility in Qingdao, Huashida has accumulated over two decades of experience in pipeline anti-corrosion equipment. The company holds 58 invention patents, 38 utility model patents, and 38 software copyrights, with core technology originating from Germany and R&D partnerships with Beijing University of Chemical Technology. Globally, Huashida operates a production base in Uzbekistan and maintains a strategic partnership with Solution Berg Pipes Company in Saudi Arabia. Equipment has been exported to Russia, UAE, Saudi Arabia, Iran, Uzbekistan, Kazakhstan, Nigeria, South Africa, India, and Thailand, with multiple repeat-order customers demonstrating long-term satisfaction. For large-diameter pipeline projects, this proven capability translates to reliable equipment that has been validated in the most demanding applications worldwide.