Ultra Large 3LPE Coating Plant Up to DN3620 mm

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

The process sequence follows the same logic as smaller lines, but the station spacing and transfer design are calculated from the pipe rather than taken from a template. Pipe is picked by crane or gantry, set on a segmented synchronous conveyor, centred, and blasted in a chamber whose wheel arrangement was chosen after the circumference study. Masking and induction heating follow, then the coating sequence: epoxy powder, adhesive, polyethylene, with the pipe turning under its own drive. Cooling water is recycled through a treatment stage, and the schedule for each diameter includes the cooling time so that a short cut does not send an under-cooled pipe to the bevelling station. End bevelling and a full circumference holiday scan close the cycle.

1. Pipe diameter: DN2540-3620mm (100-144 Inch)
2. Processing capacity: ≥250m²/h
3. Cleaning level: ≥Sa2.5
4. Materials for production: epoxy powder, adhesive, polyethylene

Standards Compliance

The applicable standard is normally named by the project owner, most often a derivative of ISO 21809-1 with project-specific layer thicknesses and test frequencies. GB/T 23257 applies to domestic Chinese projects. The preparation standard is ISO 8501-1. Where the owner specification departs from a published standard, our quotation lists the clauses we can meet and the clauses we cannot, so that the assessment is made before the contract rather than after.

Applications

Very large water transfer and diversion projects; large diameter gas transmission in exceptional terrain; industrial and port water mains; special structural tube where corrosion protection is contractually specified. Projects in this class usually combine an external three-layer coating with an internal coating, and are executed against a named owner specification with third-party inspection at the factory. We plan for that: the inspection stations, witness points and documentation trail are agreed before manufacture starts, not discovered during it.

Service & Support

Engineering deliverables include layout, foundation and load drawings, electrical schematics, PID and a full operating manual in English. Installation is supervised by 2 to 3 engineers over 15 to 30 days, planned to be complete before your first commercial consignment. Operator training continues until the team is independent, and a maintenance schedule with wear part intervals is handed over at the same time. Critical spares ship by air within 72 hours; a two-year wear parts package is available with the line.

Why Choose Qingdao Huashida

We have the reference to make this credible: our large diameter coating technology has run on a 6,600 mm internal coating project for a major water diversion scheme in southern China, which is a class of pipe far larger than most suppliers will quote. Our 3PE anti-corrosion line holds a Shandong Province First-Set Technical Equipment award, and we run our own coating plant group, so we operate what we sell. For this diameter class we will say clearly at the start whether the project is inside our proven envelope, and if a technical requirement sits outside it we will name that before the order rather than after.

---FAQ---

Q: What is the largest pipe this line can coat?

A: DN2540 mm, 100 inch. Above that the configuration moves outside our standard range and we ask to be involved at the design stage so that handling and blast geometry can be engineered specifically.

Q: Do we need to build a new workshop?

A: Usually yes, and mainly because of clear height and the blast pit. If an existing bay has 9 m clear height and a floor area of at least 120 m by 25 m in a straight line, it can often be adapted, and we will confirm this from your drawing.

Q: How much water and power does the line consume?

A: The pipe is cooled from coating temperature by water spray, so consumption is continuous and we size the recycle and treatment system with the line. Power is quoted as installed load, and we recommend a transformer at 120 percent of that figure to cover cranes, lighting and auxiliaries.

Q: Can the same line coat pipe internally as well?

A: It can be supplied as a combined external and internal coating line. The internal section is quoted separately, and the pipe handling between the two sections is designed so that the external coating does not have to be re-done.

Q: How many operators are needed?

A: Five to six per shift. The extra person over a mid-range line is normally on pipe handling, because the crane cycle for a 24 metre pipe is longer than the coating cycle.

Q: How long does the project take?

A: Manufacture and pre-delivery testing take 60 to 90 days. Site installation and commissioning add 15 to 30 days, and for a new building we prefer to be involved about four months before the line is needed.

Q: What is the investment payback?

A: It depends entirely on your contract volume and coating price, so we do not state a figure in a catalogue. We will, however, work through the arithmetic with you using your own take-off, coating thickness and labour rate, and put the assumptions in writing.

Q: Is operator training included?

A: Yes. Training is included in the commissioning scope and continues until your operators can run and adjust the line without supervision. Training is delivered in English with drawings, and we can arrange Russian-language documentation.