CB-3 / CB-3H

Overview

The BUG-O CB-3 / CB-3H is an oxy-fuel circle burner designed for single-pass square or beveled hole cutting on vessels, large-diameter pipe, domed heads and flat plate. It is a mechanised cutting solution for industrial applications where accurate circular openings, repeatable torch movement and controlled cutting geometry are required.

The CB-3 includes variable speed rotation, a 2-hose oxy-fuel machine torch, adjustable tip adaptor, vertical and horizontal torch adjustment, and a rise and fall cam. Unlike the CB-2, which is mounted on a magnetic frame, the CB-3 must be mounted from the top of the shaft using a column and boom, manipulator or suitable fixture.

The CB-3H has the same core features as the CB-3 but adds a hillside kit. This kit provides a single rise and fall motion per revolution of the machine, allowing the torch to follow the contour required for offset pipe-to-pipe weld preparation.

Recommended options and accessories

1. CWO-6210 Rotation Control Box: Controls rotation speed, travel direction, machine power and pilot light indication.
2. CWO-6110-K Rotation Control: Rotation control assembly used with the CB-3 circle burner.
3. BUG-1298 2-Hose Machine Torch: Victor 2-hose oxy-fuel machine torch supplied with the standard CB-3 configuration.
4. Harris torch configuration: The CB-3H / -H machines are supplied with a Harris torch instead of the standard Victor torch.
5. BUG-1259 Adjustable Tip Adaptor: Allows torch tip adjustment for correct cutting setup and torch alignment.
6. BUG-1252-2 Acetylene Tips: Cutting tips referenced in the CB-3 parts list.
7. CWO-1635 Racking System: Provides vertical torch positioning adjustment during setup and cutting.
8. CWO-1690 Large Horizontal Racker: Provides horizontal torch adjustment for accurate positioning relative to the cut line.
9. CWO-3205 7″ Cam Assembly: Rise and fall cam assembly used to follow the geometry of vessels, pipe and curved surfaces.
10. CWO-3895 Hillside Kit: Included with the CB-3H and used for hillside hole cutting and offset pipe-to-pipe contour following.
11. CWO-3744 Manipulator Bracket: Accessory bracket used when mounting the CB-3 to a manipulator or similar fixture.
12. Column and boom, manipulator or custom fixture: Required for operation, as the CB-3 / CB-3H must be fixtured from the top of the shaft.

Key points

• Oxy-fuel circle burner for single-pass square or beveled hole cutting.
• Designed for vessels, large-diameter pipe, domed heads and flat plate.
• CB-3H version includes hillside kit for offset pipe-to-pipe contour cutting.
• Beveled hole capacity from 1.5″ to 42″ / 38 to 1067 mm.
• Square-cut hole capacity from 4″ to 48″ / 102 to 1219 mm.
• Rise and fall cam range from 0″ to 7″ / 0 to 178 mm.
• Rotation speed range from 0.1 to 2 rpm.
• Variable speed rotation for controlled oxy-fuel cutting.
• 2-hose oxy-fuel machine torch with adjustable tip adaptor.
• Vertical and horizontal torch adjustment.
• Brushes and collector rings eliminate cable and hose wrap-up.
• Must be mounted on a column and boom, manipulator or fixture.
• 120 VAC and 240 VAC versions available.
• 100% duty cycle.
• Made in USA.

Technical advantages

The main technical advantage of the BUG-O CB-3 / CB-3H is its ability to mechanise oxy-fuel circle cutting on large industrial workpieces. Instead of relying on freehand torch movement, the machine provides controlled rotation, torch positioning and rise-and-fall movement, improving consistency and repeatability.

The rise and fall cam is essential for cutting on curved or contoured surfaces. It allows the torch to move vertically during rotation, helping maintain the required relationship between the torch and the workpiece as the machine cuts around the hole.

The CB-3H adds an important capability for offset pipe-to-pipe applications. Its hillside kit provides a single rise and fall motion per machine revolution, creating the motion required to follow the contour of an offset pipe-to-pipe weld. This makes the CB-3H more specialised than the standard CB-3 where hillside hole preparation is required.

The vertical and horizontal torch adjustment system allows the operator to set torch position, angle and standoff distance before cutting. This improves setup accuracy and supports cleaner square or beveled hole cuts.

The use of brushes and collector rings prevents cable and hose wrap-up during rotation. This allows smoother continuous operation and reduces interruption during circular cutting.

Applications

The BUG-O CB-3 is designed for oxy-fuel square and beveled hole cutting on vessels, large-diameter pipe, domed heads and flat plate. It is suitable for fabrication environments where controlled single-pass circular cutting is required.

Typical applications include pressure vessel fabrication, tank work, large pipe fabrication, domed head preparation, flat plate hole cutting, industrial maintenance, heavy repair work, fabrication workshops and field cutting operations where the machine can be mounted to a manipulator, column and boom or fixture.

The CB-3H is especially suitable for hillside hole cutting and offset pipe-to-pipe weld preparation. Its hillside kit allows the torch to follow the contour required for offset pipe intersections, making it more appropriate for complex pipe fabrication tasks than the standard CB-3.

Why choose this product

The CB-3 / CB-3H is a strong choice for companies that need repeatable oxy-fuel circle cutting on large or difficult workpieces. It is designed for controlled square and beveled hole cutting where freehand methods are too inconsistent, slow or dependent on operator skill.

The CB-3 offers practical value for general vessel, pipe, domed head and flat plate cutting, while the CB-3H adds specialised hillside cutting capability for offset pipe-to-pipe weld preparation. This allows buyers to select the correct configuration according to the geometry of their work.

For fabrication teams, the commercial advantage is improved repeatability, better control over bevel geometry, reduced manual variability and more efficient preparation for downstream welding operations.