When designing a Steel Tracked Undercarriage, total machine weight is usually one of the first parameters considered, but it should not be the only basis for the design.

Two machines may both weigh 10 tons, yet a compact drilling rig and a machine with a long working boom can require very different undercarriage configurations. The reason is simple: the undercarriage does not support a static “10-ton number.” It responds to how the weight is distributed, how the machine moves, how the ground supports the tracks, and how much traction the travel system must produce.

A steel tracked undercarriage should therefore be treated as part of the complete machine rather than as an independent track assembly.

Machine Weight Alone Does Not Define Steel Tracked Undercarriage Load

Consider two machines with the same total weight.

On the first machine, most of the mass is concentrated near the center of the Steel Tracked Undercarriage. The second machine may use a long boom, heavy attachment, drilling mast, or lifting structure that shifts the center of gravity forward or backward.

Although their total weights are identical, the loads carried by the rollers, track chains, idlers, and drive sprockets can be very different.

An offset center of gravity can change:

• Load distribution across the rollers
• Loads on the idler and drive sprocket
• Track-link wear patterns
• Stability during climbing and braking
• Undercarriage support during working operations

For this reason, sizing a Steel Tracked Undercarriage only according to total machine mass can overlook how the load is actually distributed.

For machinery with long booms, drilling structures, lifting platforms, or large working equipment, center-of-gravity position should be considered together with total machine weight.

Track Width Primarily Changes Ground Pressure

Track width is often associated with stability, but more precisely, it changes the contact area between the machine and the ground.

The basic relationship can be understood as:

Ground pressure = machine load ÷ effective track contact area

For the same machine weight, increasing the effective contact area generally reduces the pressure applied to the ground.

This is particularly useful on soft soil, mud, farmland, and other surfaces with limited bearing capacity because lower ground pressure can reduce machine sinkage.

However, wider tracks are not automatically better in every application.

Increasing track width can also increase overall machine width, turning resistance, and undercarriage mass. On hard surfaces, in confined spaces, or on machines that turn frequently, excessive track width may not improve overall performance.

The important question is therefore not “How wide can the track be?” but “How much ground contact area does this machine actually need?”

Track Length Affects More Than Stability

In addition to width, effective track contact length is another important design variable.

A longer contact length distributes machine weight over a larger front-to-rear area and can improve longitudinal stability when a long boom is extended, a platform is raised, or the machine operates on a slope.

However, an excessively long track also affects turning behavior.

Tracked machines turn by creating a speed difference between the left and right tracks, which causes part of the track to slide relative to the ground. As contact length increases, this turning resistance generally increases as well.

Track length therefore involves a balance:

Longer ground contact can improve support and stability, but may also increase turning resistance and overall size.

This is one reason drilling rigs, mobile platforms, compact construction machinery, and agricultural equipment can require different track proportions even when their total weights are similar.

The Travel Motor Must Match the Speed the Machine Actually Needs

Once the undercarriage structure is defined, another question becomes important: how should the machine travel?

Many tracked machines do not need to operate continuously at high speed. More commonly, they move slowly into a work area, adjust position, climb a slope, and then travel faster when relocating between operating locations.

This is where a Double Speed Travel Motor becomes useful.

Low-speed operation is more suitable for:

• Slope travel
• Soft ground
• Loaded starting
• Low-speed turning
• Precise machine positioning

The higher-speed range is mainly useful for normal relocation.

Therefore, travel performance should not be evaluated simply by asking, “What is the maximum speed?”

A better question is: Does the machine have enough traction in its most difficult terrain while still maintaining an acceptable relocation speed?

Hydraulic flow, motor displacement, reduction ratio, and machine weight all influence this balance.

Why Large Working Equipment Changes Undercarriage Requirements

An undercarriage does not carry load only while the machine is travelling.

When a drilling rig begins drilling, a lifting machine raises its platform, a boom extends, or a heavy attachment engages the ground, the forces acting on the undercarriage change.

For example, extending a long boom forward can increase the load on the front section of the tracks. Working on a side slope may create different loads on the left and right track assemblies. Sudden forces at the working attachment can also be transferred through the upper structure into the undercarriage.

Undercarriage design should therefore account for the machine’s working condition, not only its transport condition.

This is also why customized tracked undercarriages are often more appropriate for specialized mobile machinery than completely standardized solutions.

What Does a Compact Undercarriage Really Save?

A compact undercarriage is not simply a shorter or narrower track system.

Its greater value is efficient packaging of the travel motor, sprocket, idler, rollers, and supporting frame so that more space remains available for other machine systems.

A mobile machine may also need space for:

• Engine or battery system
• Hydraulic tank
• Pumps and valves
• Working equipment
• Lifting mechanism
• Control system

If the undercarriage occupies excessive space, it can directly restrict the overall machine layout.

Effective compact design therefore means maintaining sufficient track contact length, structural strength, and load capacity within a limited installation envelope rather than simply reducing external dimensions.

Why Steel Tracks Suit Heavy Loads and Difficult Terrain

Steel tracked undercarriages are commonly used on machinery that requires high structural strength, impact resistance, and reliable mobility over difficult terrain.

In heavy-duty equipment, vibration, traction loads, and external impact are continuously transmitted through the track chains, rollers, sprockets, and undercarriage frame.

High-strength components therefore provide more than resistance to breakage. They also help maintain correct geometry throughout the running system.

If the frame deforms significantly under load, alignment between the sprocket, rollers, and track chain can change. This can increase localized wear and travel resistance.

For a steel tracked undercarriage, durability depends not only on material strength but also on maintaining correct alignment between moving components over time.

What Information Matters in a Customized Undercarriage?

Customizing a steel tracked undercarriage involves much more than changing mounting holes.

A practical configuration should consider several machine parameters together, including total weight, center of gravity, track width, effective ground contact length, ground clearance, travel speed, and hydraulic conditions.

Many of these variables are directly connected.

For example, increasing track width affects both ground pressure and machine dimensions. Changing track length influences stability and turning resistance. Selecting a different travel motor displacement changes speed and traction. Changing the mounting position affects how upper-machine loads are transferred into the undercarriage.

The real meaning of a Customized Undercarriage is therefore to rebalance these variables according to how the complete machine is expected to work, rather than simply changing one dimension.

WEITAI Steel Tracked Undercarriages

WEITAI Steel Tracked Undercarriages are designed for construction machinery, agricultural equipment, mobile platforms, and other specialized tracked machines.

The structure uses high-strength, durable running components and can be combined with double-speed travel motors. Configurations can also be adapted to different machine dimensions, working loads, hydraulic systems, and mounting interfaces.

Instead of relying on one fixed undercarriage layout, this approach is more suitable for different types of mobile machinery because actual travel performance ultimately depends on how well the undercarriage is matched to the complete machine.

Frequently Asked Questions

1、Can two machines with the same weight use exactly the same tracked undercarriage?

Not necessarily. Even with the same total weight, differences in center of gravity, working-equipment position, track dimensions, and travel requirements can create very different undercarriage loads and stability requirements.

2、What does track width mainly affect?

Track width changes effective ground contact area and ground pressure. It also influences overall machine width, turning resistance, and undercarriage weight.

3、Why do many tracked machines use double-speed travel motors?

Working and relocation conditions require different travel characteristics. Low speed provides better traction and control, while high speed is more suitable for normal movement between working areas.

4、What is most important when customizing a steel tracked undercarriage?

The goal is not simply to change one dimension. Machine weight, center of gravity, track geometry, hydraulic conditions, required travel speed, and mounting structure should be matched as one complete travel system.