Steel Pipe Inner and Outer Wall Shot Blasting Machine

A steel pipe inner and outer wall shot blasting machine is a specialized through-feed machine. It cleans the outside surface and the bore, simultaneously or in sequence. Buyers also search for a pipe internal shot blasting machine, a steel pipe inner wall shot blasting machine or a steel pipe external shot blasting machine. This cleaning is the condition required before FBE, 3PE or coal-tar epoxy coating.

Contact us for a quotation based on the machine configuration, production capacity, and project requirements.

What do overseas buyers call this machine?

Pipe cleaning equipment is sold under different names in different markets, and buyers often search for only one half of the machine. Knowing the local name helps you compare quotations correctly.

Model codes are a second search entry point, and they tell you which half of the machine you are quoting. Chinese makers use the QGW series for pipe outer wall cleaning and the QGN series for pipe inner wall cleaning; the plain QG series covers combined external and internal units. International reference designs include the Wheelabrator class pipe descaling line and the Pangborn class internal and external pipe blast systems used on North American line pipe. Brand and model names are referenced for naming and comparison purposes only and are the property of their respective owners.

How does a steel pipe inner and outer wall shot blasting machine work?

The process runs in five stages.

1. Loading and centering

Pipes feed automatically on a roller conveyor. A centering device keeps each pipe stable. Centering accuracy decides whether the internal blast head can travel the full length.

2. External wall blasting

Centrifugal turbines throw shot at 60–110 m/s from different angles. Conveyor rollers make the pipe rotate while advancing, giving 360° dead-zone-free coverage. Mill scale, rust, old coating and weld slag are stripped. This steel pipe descaling machine process leaves bare metal.

3. Internal wall blasting — the core technology

Cleaning the bore is the technical challenge. Shot must cover the full circumference evenly. Three solutions are used:

• Cantilever lance type internal blast head — for medium and large diameter pipe. A lance enters from the pipe end, rotating and throwing shot until it passes through.
• Rotary self-propelled internal blast head — for longer pipe. The head rotates and advances along the axis under its own drive.
• Air blasting for small bore — compressed-air blasting cleans pipe where a lance cannot enter.

Lance type, insertion length and drive power follow pipe diameter, wall thickness and length. See the pipe internal blast head configurations below, or supply your pipe data.

4. Shot recirculation and dust collection

Spent shot falls to a screw conveyor. A bucket elevator lifts it to a full-curtain air-wash separator. Usable shot recirculates; fines and dust are rejected. A pulse-jet dust collector keeps emission within limits.

5. Unloading

High-pressure air blows off residual shot. Pipes discharge automatically into coating or lining.

Which model covers my pipe diameter?

Diameter is the first selection question, and it is split between the outer wall unit and the inner wall unit. The published model range is:

Outer wall models (QGW series)

Inner wall models (QGN series)

Small bore pipe from Φ50 mm is handled by the QGW100 and QGN100 models, where internal cleaning uses compressed-air blasting rather than a rotating lance. Large diameter pipe up to Φ2800 mm on the outer wall and Φ1500 mm on the inner wall is covered by the QGW2800 and QGN1500. Send your outside diameter, wall thickness and length and we confirm the exact model and lance configuration.

Which workpieces is it suitable for?

The machine is engineered for tubular products. Pangborn class builders of the United States supply comparable machines for the North American oil and gas pipeline sector. Dingtian equipment follows the same process principles, with customization and shorter lead times.

• Oil and gas — this oil and gas pipeline shot blasting system prepares transmission line pipe before FBE and 3PE coating. Also drill pipe, casing, coupling stock and other oil country tubular goods.
• Chemical and energy — boiler tubes, high-pressure heat exchanger tubes, process piping.
• Water and municipal — large diameter water mains and fire protection piping.
• Construction and structural tube — hollow sections, bridge cable ducts, pier support tubes.
• Machinery and automotive — hydraulic and pneumatic cylinder tubes, drive shafts.
• Special duty tube — wind tower inner walls, stainless steel water pipe.

Which workpieces is it NOT suitable for?

Six workpiece categories do not suit this machine:

Costs and quotation

Contact us for a quotation based on the machine configuration, production capacity, and project requirements.

Wheelabrator, Pangborn and SINTO are trademarks of their respective owners. They are referenced only to indicate comparable process technology; no affiliation, authorization or endorsement is implied or should be inferred.

Steel pipe shot blasting machine buyer FAQ

Can the external and internal walls be cleaned in one pass?

Yes. Cleaning both surfaces simultaneously or in sequence is the core design purpose. The pipe rotates and advances on the rollers. Chamber turbines cover the external wall. A lance or self-propelled head cleans the bore.

What is the difference between the QGW and QGN series?

QGW models clean the pipe outer wall and QGN models clean the pipe inner wall. The published ranges are QGW100 to QGW2800 for outer diameters from Φ50 mm to Φ2800 mm, and QGN100 to QGN1500 for bores from Φ50 mm to Φ1500 mm. A full inner and outer wall line pairs one QGW unit with one QGN unit sized to the same pipe range. If you only need one surface cleaned, you only need one series.

Does it work on welded and spiral pipe as well as seamless pipe?

Yes. The process is the same for seamless, ERW, LSAW and spiral welded pipe, because the pipe rotates and advances while fixed wheels and the internal head do the work. Two points matter on welded pipe: the weld bead must not obstruct the internal blast head travel, and heat-affected zone scale is removed like any other mill scale. Tell us the pipe type and whether the seam is internal or external at the quotation stage so we can set the lance clearance.

How do I choose between a cantilever lance and a rotary self-propelled head?

A cantilever lance suits medium and large diameter pipe, entering from the pipe end. A self-propelled head drives itself along the pipe axis, for longer pipe. Small bore pipe uses compressed-air blasting. Selection requires diameter, wall thickness and length.

Can the pipe go straight into coating after blasting?

Yes. The discharge end blows off residual shot and dust. Pipes feed directly into coating. This is the standard line pipe pretreatment step for FBE and 3PE coating. Cleanliness and roughness follow the coating specification.

How long and how large a pipe can it process?

Published model ranges cover outside diameters from Φ50 mm to Φ2800 mm on the outer wall and bores from Φ50 mm to Φ1500 mm on the inner wall, at cleaning speeds of 1–10 m/min depending on model. Pipe length is set by conveyor load capacity, chamber size and lance insertion length rather than by a fixed catalogue figure. Supply pipe diameter, wall thickness, length and weight, and we determine the configuration.

Is it fully automatic?

Loading, centering, conveying, rotation, blasting, shot blow-off and discharge run automatically under PLC control on the standard configuration. The operator loads pipe onto the infeed rollers and unloads at the discharge end. Where a manual air blast touch-up station is added for blind ends and fittings, that station is operator-controlled by design.

How is the shot recirculated?

Spent shot falls to a screw conveyor, then a bucket elevator lifts it to an air-wash separator. Usable shot recirculates; broken fines are rejected. Loss is far lower than single-use abrasive processes.

Does dust emission meet regulations?

A pulse-jet reverse-flow dust collector is standard. Emission is designed to the environmental standard of the project location. Airflow and cartridge count follow the target standard.

Is the internal blast head a wear part?

The blades, cages and liners of the internal head are wear parts. Intervals depend on shot type, rust condition and daily hours. The internal unit rotates at high speed inside the pipe, making it the main maintenance point. Overseas customers should hold stock spares.

About Jiangsu Dingtian

Jiangsu Dingtian Derusting & Painting Equipment Co., Ltd. is a China source factory for shot blasting machines, abrasive blasting rooms and coating lines. For pipe cleaning, the process route matches the international mainstream used on oil and gas line pipe pretreatment equipment. Chamber width, conveyor load and blast head type are custom-engineered.

Contact us for a quotation based on the machine configuration, production capacity, and project requirements.

Contact

Send pipe outside diameter, wall thickness, length, weight, rust condition and daily output. You get a free model recommendation and a steel pipe shot blasting machine price quotation.

Email: dtcx@dt-shotblasting.com | WhatsApp / WeChat: +86 158 9516 5618 | WeChat ID: cxj999888

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Ready to specify this machine? Send workpiece drawings, material and dimensions through the inquiry form below. Our engineers confirm the model, blast wheel layout and abrasive specification before you order.