Improving test consistency while minimizing bubble interference in end-of-line validation

This project is the result of a successful collaboration in which Incotech Ltd played a key role in introducing and implementing the solution at the customer site.

Background

Hyster Yale Material Handling, a USA-owned multinational and one of the world’s top forklift truck manufacturers, required robust and repeatable end-of-line testing for their gearboxes. These gearboxes, used in off-highway and material handling vehicles, often release contaminant particles and air bubbles during early operation. While these conditions often compromise the accuracy of conventional particle counters, rigorous testing remains essential to ensure oil cleanliness before shipping to maximize the long-term life of the asset. To meet the OEM’s strict cleanliness standards, they partnered with Incotech Ltd, a UK-based engineering company with around 20 employees specializing in automation and test rigs. Incotech developed a custom test bench and integrated Atten [2]’s OilWear sensor as a solution.

 

Challenge

Overcoming bubble presence in gearbox validation

Each gearbox undergoes validation before being assembled into the forklift truck. During early operation, it is common for the gears and clutch to release particles and air bubbles. The system reduced oil flow from a 1” pipe to a 6mm inlet and returned it at a low-pressure point, a pressure regime where traditional sensors failed or required costly adaptations (e.g. 100 bar pressurization to eliminate bubbles).

Incotech integrated Atten2’s OilWear sensor into the gearbox test bench to monitor oil cleanliness in real time. The sensor was installed on a bypass line pulling oil from the cooling and lubrication circuit, measuring key parameters such as particle and bubble count, particle size distribution, and ISO 4406 cleanliness codes.

Benefits

Reduced testing time: No need to wait for air bubbles to settle.

Reliable particle counting: Consistent performance even under foamy or bubbly conditions.

Simplified test bench design: Eliminates need for high-pressure bubble suppression systems.

 

We’ve tried other particle counters before, but they failed in bubbly conditions. With Atten[2]’s OilWear S, we get reliable results even when the oil looks like cloudy beer. It just works.

— Paul Abbott, Incotech Ltd

 

Value for the client

• Confidence in test repeatability and reliability.
• Increased confidence in the test rig’s performance and measurement consistency.
• Better traceability for gearbox cleanliness before assembly.

 

 

Results and scalability

The success of this integration demonstrates that Atten2’s OilWear technology excels where traditional sensors struggle, maintaining measurement integrity even in challenging low-pressure environments characterized by high oil aeration. Its ability to filter out air bubbles of the particle count makes it the definitive solution for end- of-line validation systems, where speed and accuracy are non-negotiable. This performance is further validated by its proven deployment at a world-class OEM in the material handling sector, confirming that the system is not only a technical breakthrough but a field-hardened asset for global manufacturing leaders.

While no direct environmental or safety impact was reported, the system’s reliability minimized retesting and oil waste, contributing to operational efficiency.

This solution is highly applicable to other testing environments with aerated or foaming oils, including:

• Gearbox and powertrain assembly lines
• Hydraulic or automotive test rigs
• Any low-pressure oil circuit prone to bubble formation

 

Visit atten2’s website here.