ESCO® Ultralok® U45 Teeth & Adapters

System Definition U55

The U55 system size defines the engineered interface between tooth and adapter in the upper heavy-duty segment of the ESCO® Ultralok® system.

Typical application range:
Crawler excavators and large wheel loaders in the approx. 45–70 tonne class.

Note:
Machine class serves exclusively as a reference value and is not an identification criterion. The decisive factor is the stamped system size “U55” on the existing component.

The locking mechanism is integrated into the tooth. Separate hammer-retained pins are not required. The system supports controlled tooth replacement in heavy-duty environments.

Cutting Edge and Lip Thickness within the U55 System

Within the U55 segment, different adapter designs are available to accommodate varying cutting edge thicknesses.

Documented adapter configurations within the U55 system include:

50 mm cutting edge (e.g. 2-leg adapters / classic weld-on adapters)
60 mm cutting edge (excavator adapters)
65 mm cutting edge (loader adapters)
70 mm cutting edge (1-1/2 bottom leg heavy excavator adapters)

Selection is always adapter-dependent.

In addition to the system size, the actual lip thickness is the primary selection criterion.

Excavator Tooth Geometries within the U55 System

For heavy earthmoving, rock and mining applications, the following tooth geometries are available:

U55S – standard
U55C – chisel
U55P – pick
U55T – twin
U55F – flare

Heavy Back variants with increased wear volume:

U55SHB
U55PHB
U55THB
U55CHB
U55HHB

PX and CP Variants – Penetration and Rock Applications

U55PX / U55PXHB – Pick Xtreme for maximum penetration
U55CP / U55CPHB – Chisel Penetration for tough, compacted materials

These geometries are designed for highly abrasive and massive rock conditions.

Loader Tooth Geometries within the U55 System

The U55 portfolio includes dedicated loader tooth variants:

U55A – loader tooth
U55AHB – heavy back loader tooth
U55AP – abrasion penetration
U55APHB – abrasion penetration heavy back

These geometries are designed for large wheel loaders operating in quarry and crusher environments.

Adapter, Corner and Center Components U55

The U55 system includes massive adapter designs for different installation configurations:

Weld-on adapters
1-1/2 bottom leg adapters
2-leg adapters
Loader adapters
Corner adapters left / right
Center adapters

Examples of adapter configurations within the system:

50 mm adapters (e.g. 4831A-U55, 8801A/B-U55)
60 mm adapters (e.g. 3811A-U55)
65 mm loader adapters (e.g. 8813A-U55)
70 mm heavy excavator adapters (e.g. 3858A/B-U55)

In mining and hot slag applications, 2-leg adapters with 50 mm cutting edges are frequently combined with the large U55 tooth system.

Original Accessories and Tools

The U55 system also includes:

PB31CG – heavy-duty pry tool
84001 – cleaning and service tool
Box variants and locking components

Original tools support proper removal procedures in heavy-duty environments.

Position within the Ultralok® Hierarchy

The U55 size is positioned within the Ultralok® system between:

U45 – for approx. 35–50t machines
U55 – for approx. 45–70t machines
U60 – for approx. 70t and above

Selection is determined exclusively by the stamped system size on the component.

→ Other sizes: [U20] | [U25] | [U30] | [U35] | [U40] | [U45] | [U60]

Technical Identification Before Ordering

Before placing an order, verify:

Is “U55” stamped on the existing component?
What is the cutting edge or lip thickness (50 / 60 / 65 / 70 mm)?
Which adapter configuration is installed?
Which tooth geometry matches the application profile?

If uncertain, LIS® technical support will assist with correct system identification.

Note: ESCO® and Ultralok® are registered trademarks of their respective owners.