Pipe Coating Equipment

Pipe coating equipment is used to prepare, heat, coat, cool and inspect steel pipes before they are released for pipeline anti-corrosion service. For large-diameter welded pipes, the equipment is not only a coating machine, but a complete production line that controls surface preparation, internal coating coverage, external coating bonding, cooling stability and final inspection.

This pipe coating equipment is designed for internal FBE coating and external 3PE anti-corrosion coatings on large-diameter steel pipes. The line covers pipe feeding, storage platform, external shot blasting, internal shot blasting, medium-frequency heating, internal epoxy powder spraying, external epoxy powder spraying, AD adhesive and PE extrusion side wrapping, circulating water cooling, inspection, pipe end grinding, marking and final packing.

For procurement teams, the main concern is not only whether the equipment can apply coating. The more important points are pipe size range, pipe weight capacity, heating power, coating process stability, inspection method and whether the final coated pipe can meet project acceptance requirements.

Pipe Coating Equipment Specifications

The following configuration is suitable for large-diameter welded steel pipes requiring both internal coating and external coating before delivery to buried pipeline, water transmission or industrial anti-corrosion projects.

Item	Technical Data	Procurement Check Point
Applicable Pipe OD	φ508–φ1620 mm	Confirm the final pipe range before line design
Pipe Length	8.5–13 m	Affects conveyor length and workshop layout
Max Wall Thickness	18 mm max	Related to pipe weight and heating load
Max Pipe Weight	12 tons per pipe	Important for rack, roller and transfer vehicle design
Applicable Pipe Type	Spiral welded pipe and longitudinal welded pipe	Suitable for SSAW and LSAW pipe coating projects
External Coating Capacity	3PE ≥350 m²/h	Used to estimate daily output
Internal Coating Capacity	Up to 260 m²/h	Check with pipe ID and coating thickness
Compressed Air Pressure	0.6–0.7 MPa	Air should be free from oil, water and impurity particles
Cooling Water Requirement	Equipment: 150 m³/h; product cooling: up to 200 m³/h	Confirm workshop water supply and cooling system

Internal Coating System for FBE Epoxy Powder Spraying

The internal coating section is configured for FBE epoxy powder spraying inside large-diameter steel pipes. Before coating, the inner surface is cleaned by internal shot blasting to remove rust and create the required anchor pattern. After blasting, the pipe passes through an internal purge process to remove residual dust before heating and spraying.

During operation, the spray gun trolley sends the internal spray gun into the pipe. The pipe continues moving through the medium-frequency heating section until it reaches the required temperature for epoxy powder application. The internal epoxy powder spraying system applies the coating on the inner wall, while the powder recovery system collects unused powder to support stable production and cleaner operation.

This section is important for water transmission pipes and other pipeline projects where the internal pipe surface must be protected before hydrotest, commissioning and long-term service.

External Coating System for 3PE Anti-Corrosion Coatings

The external coating section is designed to form 3PE anti-corrosion coatings on the outer surface of steel pipes. After external shot blasting and surface dust treatment, the pipe is heated by a medium-frequency heating system. Epoxy powder is then applied as the first corrosion protection layer, followed by AD adhesive and polyethylene extrusion side wrapping.

The finished 3PE structure provides external anti-corrosion protection for buried steel pipeline service. For pipeline projects, external coating quality is usually judged by surface preparation, bonding between layers, coating continuity, cooling stability, holiday detection and pipe end cutback condition.

In this line, the external coating section is not only a PE wrapping unit. It includes surface cleaning, heating, epoxy powder spraying, adhesive application, PE extrusion, water cooling, inspection, pipe end grinding, marking and packing. This makes the system more suitable for project-based anti-corrosion coatings where inspection and release records are required before shipment.

Complete Pipe Coating Equipment Process Flow

A complete pipe coating line should show the buyer how steel pipes move through each process section, where coating quality is controlled and where inspection takes place.

Process Step	Function	Key Control Point
Pipe Feeding	Transfers qualified pipes into the coating line	Pipe alignment and stable handling
External Shot Blasting	Removes rust and contaminants from the outer surface	Sa2.5 surface preparation
Internal Shot Blasting	Cleans the inner pipe surface before internal coating	Internal anchor pattern and dust control
Internal Purge	Removes residual dust after blasting	Clean inner wall before epoxy spraying
Medium-Frequency Heating	Heats the pipe before epoxy powder application	Temperature stability before coating
Internal Epoxy Powder Spraying	Applies FBE coating on the inner pipe wall	Internal coating coverage and powder recovery
External Epoxy Powder Spraying	Applies epoxy base layer on the outer pipe surface	Bonding base for 3PE coating
AD Adhesive and PE Extrusion	Forms adhesive and polyethylene layers	3PE layer bonding and coating continuity
Water Cooling	Cools and sets the external coating layer	Coating shape and surface stability
Inspection and Pipe End Grinding	Checks coating condition and prepares pipe ends	Holiday detection, cutback and field joint preparation

Main Components of Pipe Coating Equipment

For procurement review, the equipment scope should be clear before technical and commercial comparison. A complete pipe coating equipment package may include the following sections.

Equipment Section	Main Configuration	Function in Coating Line
Internal Shot Blasting System	Two internal blasting units for different pipe ranges	Inner surface rust removal before internal coating
External Shot Blasting System	Blasting chamber, shot blasters, hoist, separator and dust removal system	Outer surface cleaning and anchor profile formation
Spiral Conveyor Line	Normal-temperature and high-temperature roller sections	Pipe rotation and movement through each coating stage
Internal Purge System	Dust box, purge fan, trolley and rotary platform	Removes residual dust after internal blasting
Internal Epoxy Powder Spraying System	Internal spray gun, powder chamber and recovery system	Applies FBE coating to the inner pipe wall
Medium-Frequency Heating System	1500KW heating system with closed cooling tower	Heats pipe before internal and external epoxy coating
External Powder Coating System	External powder room, recovery system and 12 electrostatic spray guns	Applies the epoxy base layer for 3PE coating
Extruder System	One 200/33 extruder and one 80/30 extruder	Applies AD adhesive and PE layer
Water Cooling System	Cooling water spray, isolation frame, pumps, cooling tower and piping	Cools and stabilizes the external coating
Electric Spark Inspection	Maximum detection voltage: 25KV	Checks coating discontinuity and holidays

Inspection and Quality Control Points

For anti-corrosion coatings, inspection should start before coating begins. Pipe dimensional error, weld bead height, surface cleanliness and handling stability all affect the final coating result. Before entering the coating line, the pipe should meet the required dimensional condition, including OD tolerance, ovality, straightness and smooth weld transition.

Surface preparation is a key release point. Both internal and external shot blasting are designed to achieve Sa2.5 rust removal grade. After internal blasting, dust must be removed before epoxy powder spraying. For the external 3PE coating process, surface dust treatment, heating stability, epoxy powder coverage, adhesive application and PE extrusion continuity should be controlled before cooling.

Final inspection should cover coating appearance, coating continuity, pipe end grinding condition and electric spark inspection. The line includes electric spark inspection with a maximum detection voltage of 25KV, which is important for checking coating holidays before the finished pipes are marked and packed.

Applicable Standards for Anti-Corrosion Coating Production

The coating equipment can be configured according to the required project standard. The standard should be confirmed before technical proposal preparation, because it affects coating structure, surface preparation, inspection method and documentation scope.

Applications of Pipe Coating Equipment

Buried Steel Pipeline Before Trench Lowering

For buried steel pipeline projects, external anti-corrosion coating must resist soil corrosion, transportation impact, lowering-in damage and backfilling stress. External 3PE coating is commonly selected because the epoxy layer provides corrosion protection, the adhesive layer supports bonding and the PE layer improves mechanical protection.

This pipe coating equipment helps pipe manufacturers complete factory-applied anti-corrosion coatings before pipes are shipped to the construction site. Compared with temporary field coating, factory coating gives the buyer better control over surface preparation, heating, coating continuity and inspection release.

Water Transmission Pipe With Internal FBE Coating

For water transmission pipelines, internal coating is used to protect the inner pipe wall and reduce corrosion risk during service. The internal FBE coating section is suitable for projects where the pipe inner surface must be cleaned, heated and coated before hydrotest, commissioning and long-term operation.

The combination of internal epoxy coating and external 3PE coating is suitable for large-diameter water pipeline projects where both inner wall protection and buried external corrosion resistance are required.

Large-Diameter Welded Pipe Coating Before Field Welding

Large-diameter SSAW and LSAW pipes require stable handling during blasting, heating, spraying, extrusion and cooling. Pipe weight, pipe straightness, weld bead height and roller load all affect continuous coating operation.

This equipment configuration is designed for heavy welded pipes. The pipe transfer vehicle, spiral conveyor line, pipe rack, operation vehicle and bevel grinding system help move, position and release the pipe through the coating process. Pipe end grinding also prepares the cutback area for field welding and joint coating.

Why Choose Octal for Pipe Coating Equipment Projects

Octal supports pipe coating equipment projects from technical clarification to equipment configuration and procurement review. Before preparing a quotation, we help customers confirm pipe OD range, pipe length, wall thickness, pipe weight, coating type, standard, production capacity and inspection requirements.

For buyers, this reduces the risk of selecting an under-sized line or paying for unnecessary capacity. It also helps align the technical proposal with the real project scope, including internal FBE coating, external 3PE coating, pipe handling system, heating power, inspection points and documentation.

Octal can support project teams with equipment scope review, process flow clarification, technical proposal preparation and communication with the production line manufacturer.

Ordering Notes for Pipe Coating Equipment

To prepare a suitable technical proposal and quotation for pipe coating equipment, please confirm the following information:

1. Pipe OD range
2.Pipe length range
3.Wall thickness and maximum pipe weight
4.Pipe type: SSAW, LSAW, ERW or seamless
5.Required coating type: internal FBE, external 3PE, 3LPE, 3LPP or other coating
6.Required coating standard
7.Target production capacity
8.Workshop layout and available space
9.Power supply voltage and frequency
10.Compressed air and cooling water conditions
11.Inspection and testing requirements
12.Destination country and delivery schedule

FAQ

Q1: What information is needed before quoting pipe coating equipment?

Please confirm pipe OD range, pipe length, wall thickness, max pipe weight, coating type, required standard, target capacity, workshop layout, power supply, compressed air and cooling water conditions.

Q2: Can this line support both internal coating and external coating?

Yes. The line can be configured for internal FBE coating and external 3PE anti-corrosion coatings, including shot blasting, heating, spraying, extrusion, cooling and inspection.

Q3: What pipe sizes can this pipe coating equipment handle?

This configuration is designed for φ508–φ1620 mm steel pipes, with 8.5–13 m pipe length and maximum pipe weight up to 12 tons per pipe.

Q4: What inspection points should buyers check before acceptance?

Key points include Sa2.5 surface preparation, heating stability, coating appearance, pipe end treatment, marking, and electric spark holiday detection up to 25KV.

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