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Buy Internal Pipe Blasting Machines – Pipe Diameter and Blasting Method Are Key Factors

Internal pipe blasting machines are specially designed to uniformly remove rust, scale, and contaminants from cylindrical inner surfaces and prepare them for coatings or linings. A standard straight blast nozzle can reach the inside wall of a pipe only to a limited extent and requires significant manual effort. Special pipe interior blasting heads, on the other hand, direct the blast radially or all around the inner surface via rotating nozzles.

The current product range includes systems for very small pipes with inner diameters ranging from 19 to 50 mm, as well as solutions ranging from approximately 65 mm up to large pipe diameters of 1,500 mm. Depending on the pipe size, the blasting principle, centering, nozzle configuration, and compressed air requirements vary significantly.

Small pipes with an inner diameter of 19 mm or more

For very small internal pipe diameters, particularly compact internal pipe blast heads are used. In the current product lineup, this range starts at 19 mm and extends to approximately 50 mm for the corresponding systems. A special deflection geometry directs the abrasive media to the pipe wall, even though there is no space for a conventional large blast head.

Particular attention must be paid to abrasive grit size and moisture content, especially with small diameters. Material that is too coarse or clumped together can block narrow blasting paths. At the same time, even a comparatively small internal pipe blast nozzle requires a powerful compressed air supply.

Fixed deflector cones for medium-sized pipe diameters

For pipe inner diameters ranging from approximately 65 or 75 to 300 mm, systems are used in which the blast stream strikes a central deflector head or deflector cone. This deflects the abrasive media radially toward the inner wall of the pipe. The design does not require high-speed rotating nozzles and is comparatively simple in construction.

To achieve a uniform result, the blast head must be positioned as precisely as possible along the pipe’s axis. Depending on the diameter, centering sleeves or centering carriages are used. Even a significantly off-center position can cause one side to be blasted more intensely and the opposite side less so.

Rotary Internal Pipe Blasting Machines for Large Diameters

For larger pipes, rotating systems with two blast nozzles are used. The nozzles move around the pipe’s axis and continuously treat the inner wall during axial feed. The product range includes such systems for pipe diameters ranging from approximately 200 or 305 mm up to 915 mm. Large chassis systems cover pipe inner diameters up to 1,500 mm.

The advantage lies in high and consistent all-around performance. At the same time, the technical demands on the compressed air supply and alignment increase. Since two nozzles operate simultaneously, the combined air demand of both nozzles must also be taken into account.

Nozzle size determines the compressor requirements

Internal pipe blasting machines can require significant amounts of compressed air. Even for smaller systems, the demand can already be in the range of several cubic meters per minute. Rotating dual-nozzle systems with 8 or 9.5 mm nozzles can reach double-digit cubic meter values per minute, depending on the operating pressure.

The compressor must deliver the required flow rate under actual blasting load. Long supply lines, blast hoses that are too small, tight couplings, and filters cause additional pressure losses. Therefore, the system should be designed with a margin of capacity and not just barely meet the calculated nozzle requirements.

Match the feed rate to the blast pattern

Internal pipe blasting equipment is moved axially through the pipe. If the feed rate is too fast, areas will not be adequately treated. If it is too slow, the surface will be blasted for an unnecessarily long time, increasing consumption. To ensure reproducible results, the working pressure, rotational speed or blast distribution, abrasive flow rate, and feed rate should be kept as constant as possible.

In rotating systems, both nozzles must wear at a similar rate. Nozzle bores of different sizes alter air consumption and reaction forces and can lead to imbalance or an uneven spray pattern.

The blast pot and blast hose are part of the overall system

Internal pipe blasting machines are generally not standalone blast pots. They are connected to a suitable pressurized blasting system. The blast pot must provide a sufficient supply of abrasive media and be compatible with the specified nozzle size. The blast hose must also have a sufficiently large inner diameter to prevent unnecessary pressure drop at the internal pipe blasting machine.

Buy internal pipe blasting equipment – Measure the Application Precisely

Anyone looking to purchase internal pipe blasting equipment should first determine the pipe ID, pipe length, desired surface finish, abrasive media, and available compressor power. Based on this information, you can then decide whether a small deflection head, a centered deflection system, or a rotating dual-nozzle machine is required.

A complete system design is particularly important for large piping systems. A technically suitable blast head alone is not sufficient if the compressor, blast pot, blast hose, or centering mechanism do not support the required flow rate and ensure uniform flow.