Sealed Dry Track Chains for Crawler Undercarriages

What Are Sealed Dry Track Chains?

Sealed dry track chains use a joint system consisting of pins, bushings and seals. The seals help reduce the ingress of dirt, moisture and abrasive material into the joint area.

The term sealed dry does not mean the chain is unsealed. It describes a sealed track chain design without the permanently enclosed oil or grease lubrication systems typically associated with oil-lubricated or grease-lubricated track chains.

Track Chains, Track Links and Undercarriage Chains

In international undercarriage terminology, complete chain assemblies are commonly referred to as Track Chains or Track Chain Assemblies. Individual chain links are known as Track Links.

Depending on the industry and application, these components may also be referred to as undercarriage chains, crawler chains or steel track chains. Correct identification always depends on chain pitch, link count, master link configuration and existing undercarriage specifications.

Pins, Bushings and Seals

Pins and bushings form the articulation points of the track chain. During operation they are subjected to tensile loads, impact forces, articulation movement and contamination.

Seals help protect the joint area from foreign material. Damaged seals, worn bushings or excessive joint play may contribute to chain elongation, irregular chain movement and increased loading of other undercarriage components.

Chain Pitch, Link Count and Undercarriage Geometry

Correct identification of a sealed dry track chain requires verification of chain pitch, link count, master link design and undercarriage geometry.

The chain pitch must match the sprocket, idler and overall undercarriage configuration. The link count determines the overall chain length. Even minor dimensional differences can prevent compatibility with the existing undercarriage.

Press-Fit Master Pins, Master Links and Repair Links

Many sealed dry track chains use press-fit master pins, dedicated master links or split connection systems. These components affect chain installation, removal and repair procedures.

During repairs, repair links and master links must match the existing chain specification. Differences in pitch, pin diameter, master link design or chain construction can affect interchangeability.

Typical Applications

Sealed dry track chains are used in a wide range of crawler undercarriages. Typical applications include excavators, specialist machinery, mobile screening plants, crushing equipment, material processing machines, crawler carriers and other machines operating with steel track systems.

The appropriate chain design always depends on the machine manufacturer, undercarriage configuration, chain pitch, link count and technical requirements of the existing system.

Typical Wear Patterns

Sealed dry track chains should be inspected when chain elongation, excessive joint play, damaged seals, irregular chain movement or visible wear on pins and bushings is detected.

Worn sprockets, idlers, track rollers or carrier rollers can also increase loads on the track chain. For this reason, the complete undercarriage system should always be evaluated during repair or replacement work.

Sealed Dry Track Chains within the Undercarriage System

A sealed dry track chain operates as part of a complete crawler undercarriage. The sprocket engages the chain, the idler guides the chain assembly, the track adjuster maintains chain tension, track rollers support the machine weight and carrier rollers guide the upper chain run.

Track shoes are mounted to the chain and transfer machine loads to the ground. If the chain and track shoes are supplied as a pre-assembled unit, the assembly is classified as a complete track group. Related chain categories include oil-lubricated track chains and grease-lubricated track chains.

How Is the Correct Track Chain Identified?

To identify a suitable sealed dry track chain, chain pitch, link count, master link configuration, machine application and existing undercarriage data should be verified.

The LIS® Undercarriage Finder helps identify suitable undercarriage components based on manufacturer, model, machine version and serial number. Access is available through a free LIS® customer account.

Sealed Dry Track Chains from LIS®

The LIS® range includes sealed dry track chains, undercarriage chains, Track Chains and Track Links for numerous crawler undercarriages, specialist machines and steel track applications. Selection is based on technical undercarriage specifications and the respective machine configuration.