CAT 320 Tunnel Piling Arm | Low-Profile Excavator Pile Driving Boom

EXCAVATOR PILE DRIVING ARM & BOOM

The CAT 320 Tunnel Piling Arm is a specially engineered excavator attachment designed for Caterpillar 320 series excavators (20–22 ton class), optimized for tunnel, underground, and confined-space pile driving operations.

Unlike standard piling booms, this tunnel-type piling arm features a compact and low-profile structural design, allowing stable operation in environments with limited height, restricted space, and complex working angles, such as tunnels, underground passages, culverts, and metro foundation projects.

The arm structure is reinforced using high-strength steel plates with optimized stress distribution to handle vertical load and vibration generated during pile driving. Precise alignment design ensures improved pile verticality, while maintaining smooth control and machine balance.

Each CAT 320 tunnel piling arm is custom-built based on tunnel height limits, hammer specifications, pile type, and jobsite conditions, providing a practical and reliable solution for specialized underground construction projects.

 ▎KEY FEATURES

✔ Tunnel-Specific Compact Design

Low headroom structure suitable for underground and confined spaces.

✔ Reinforced Load-Bearing Structure

Designed to withstand continuous pile driving vibration and impact.

✔ Stable Vertical Control

Improves accuracy of pile positioning in limited working space.

✔ Optimized Machine Balance

Ensures safe and smooth operation under restricted conditions.

✔ Custom Compatibility

Supports vibro hammers and hydraulic pile drivers as required.

 ▎CONFIGURATION SITUATION

 ▎STEEL CUTTING

The incision is flat to ensure the accuracy of cutting steel plates

 ▎GROOVE WELDING

Before welding, we have use big edge milling machine mill(taper process) the edge of the sheet. So the welding can go to the internal of the steel-sheet and make the structure have higher performance.

Orbital welding machines are used for welding, and manual strengthening and welding are performed at corners and reinforcements.

Our boom and arm are large-welded box structure and thick or multi-plates for high-stress areas.

Also the inside have strength plate make it more stronger.

 ▎LARGE BORING MACHINE -- BUTT BORING

The processing efficiency is higher, the precision is better, and the product quality and labor efficiency are greatly improved.

 ▎SURFACE TREATMENT OF WORKPIECE--SHOT BLAST 

The small steel balls of the large shot blasting machine are used to hit the surface of the workpiece to remove the rust and small impurities on the surface of the steel plate, so that the surface of the workpiece presents the original metallic luster and increases the adhesion of the primer.

 ▎PRIMER AND PAINT TREATMENTS

Spray with the same paint as the brand excavator factory to ensure consistent color.

 ▎HIGH PRESSURE HARD PIPE & PIPELINE BENDING TREATMENT

1. Friction welded flange and oil cylinder - use machine high-speed friction welding, which has higher efficiency and avoids artificial false welding and air bubbles.

2. Automatic pipe bending machine - use numerical control to control the degree of bending of the pipeline, and automatically bend the seamless steel pipe, with higher precision.

 ▎PAINT / PACKAGING / TRANSPORTATION SERVICES

1.The color paint is consistent with the brand excavator factory (customizable color), using high-quality paint to make the product more delicate and beautiful.

2. We use stretch film to package the product. (Three-plywood wooden frame needs to be noted)

3. We have cooperated with many shipping companies in China for many years,and the transportation service and efficiency are very good. (Recommend FOB/CIF/CNF)

 ▎CERTIFICATTES & FACTORY HISTORY

We were originally affiliated to a Singaporean private factory in China. We have always only served the excavator industry and have a lot of data and manufacturing experience. Provide professional excavator accessories for dealers in many countries around the world.We insist on quality first, and deal with details so that brand dealers appoint us as partners.

（Information and photos are not displayed to protect the privacy of customers）