TPU Sealing Solution for Hydraulic Cylinder
Client introduction
Our project client is known for their high-quality rodless cylinders, which are widely used in various automated machinery and heavy-duty applications. Their products are essential for ensuring efficient and reliable operations in industries such as printing, spraying, automatic feeding, plastic manufacturing, and packaging.
The challenge
Their technical team faced three core problems in hydraulic cylinder seal development.
First, there was a significant risk of seal failure when using stainless steel or iron reinforcement strips. The rigid friction between these metal materials and TPU and NBR seals creates micro-damage to the sealing surface, resulting in leakage rates as high as 0.15cc/min under extreme working conditions.
Second, the seals experienced substantial life loss. The metal reinforcement strips have an edge sharpness of Ra0.8μm, and when operating under a working pressure of 10MPa, the service life of nitrile rubber seals drops dramatically.
Third, attempts to replace metal with PVC have failed to provide a viable solution. While PVC does address the wear problem, it lacks durability. After only 3 months of use in environments above 55°C, the PVC material develops a permanent deformation.
Our solution
Our first technical solution was to embed a copper-plated steel wire in our TPU solution, which increases tensile strength. We adjusted our V-belt mold to achieve ±0.05mm positioning accuracy of the steel wire layer.
Besides that, we introduced a nitrogen-assisted cooling process to eliminate cross-sectional deformation caused by internal stress.
Results
Our client shared that we helped them achieve a 3 times lifespan leap for their hydraulic cylinders by adopting our TPU sealing solution. It solved an industry-wide problem and we benefited from the increased demand due to our factory’s production capacity, producing 420,000 linear meters a year.
Compared with the previous imported solution, we reduced the unit cost by 28%.
Our client commented:
This steel wire reinforced TPU sealing strip not only solves the wear and leakage problem that has plagued the industry for ten years, but also creates a technical route for flexible reinforcement parts to replace metal parts, which is expected to drive the technical upgrade of the entire hydraulic sealing industry.
