U-cup TTU: page 5
TTU seals are NBR rod seals for single- and double-acting hydraulic cylinders. They are the correct choice when the temperature drops below -30°C and polyurethane is no longer flexible, or when the fluid in the system is not chemically compatible with standard PU. They can be found in equipment operating in northern conditions, in older machinery with groove dimensions not covered by modern profiles, and in systems with special fluids — situations where cold-temperature performance and chemical compatibility matter more than abrasion resistance. Complete data sheets by size and compatible fluids are available at hydsealstore.ro, with filters by minimum operating temperature.
Technical Specifications and the Role of TTU Seals in Industry
TTU seals operate between -40°C and +100°C, at pressures of 160-250 bar. The wider profile compared to compact versions distributes pressure over a larger surface area, which reduces wear at high sliding speeds and contact temperature. They seal in both directions — suitable for double-acting cylinders. Compatible with HLP and HVLP oils and some HFC or HFAE fluids, where polyurethane fails within a few weeks. The NBR hardness is selected according to the maximum pressure in the system, between 70 and 90 Shore A. Complementary components are available in the range of hydraulic seals, including versions for older cylinders with non-standardized grooves.
Durability, Flexibility, and Resistance in Heavy-Duty Applications
The key advantage of NBR over polyurethane is its performance in extreme cold. Below -30°C, PU becomes rigid and loses its sealing capability within the first hours of operation — NBR remains flexible and does its job. That is why TTU is the first choice for forestry or mining equipment in regions with severe winters, for older machinery with non-standard dimensions, and for systems where the fluid is not compatible with PU. For machinery that starts in the morning at temperatures of -25°C and operates all day, TTU makes the difference between immediate startup and 30 minutes of warm-up. The rod wiper completes the protection — compatible versions are available in the range of hydraulic wipers, including those for environments with dust and water.
Recommendations for Installing and Maintaining TTU Seals
Check the dimensions — the rod diameter, housing diameter, and groove depth. Confirm that the fluid is compatible with NBR (the list is in the technical data sheet, especially for oils with special additives or synthetic fluids). The groove must be thoroughly cleaned and inspected for scratches. The seal must be inserted correctly oriented in relation to the direction of pressure and lightly lubricated beforehand. Replace the wiper at the same time — there is no point in having a new seal protected by a worn wiper. For older cylinders with marginal grooves, measure again with a caliper before ordering. Alternative profiles are listed in the range of hydraulic seals, with options for intermediate dimensions that are missing from the standard catalog.
Advantages of Purchasing TTU Seals from Hydraulic Seals Store
TTU seals are a solution for hydraulic cylinders where the use of an NBR seal is required, including applications with low temperatures or certain fluids for which polyurethane is not suitable. At Hydraulic Seals Store, you can check the available sizes and versions designed for single- and double-acting cylinders.
Before ordering, check the rod diameter and groove dimensions, and if the system uses a special fluid, check the material compatibility. For applications at very low temperatures or under less common conditions, the choice of material is particularly important. If you need help, our team can guide you toward the appropriate TTU version.