DESCRIPTION
The PU-TDT is a tandem seal designed for use with telescopic cylinders. It is made of polyurethane and has two sealing lips on the inside. Prior to fitting, these lips protrude beyond the nominal diameter of the seal. Following installation, seal compression forces the lips against the telescopic cylinder stages, thereby providing a sealing function at zero pressure.
Under increasing pressure and compression of the seal, the sealing lips are pressed against the telescopic cylinder stages. The sealing edge of the second lip produces an annular cavity, where any oil that passed the first lip is collected. The oil is held back by the sealing edge such that the emerging telescopic cylinder stages remain dry. During the return stroke, the collected oil is forced back into the cylinder.
It is recommended that the PU-TDT seals are used in conjunction with WRFI type bearings to produce a simple and compound construction for all telescopic cylinder stages.
SEAL INFORMATION
Durometer (Shore A): 87
Temperature Range (F): -31 TO 212
Max Pressure (psi): 5200
Extrusion Gap at Various Pressures (mm):
- 1,500 PSI: 0.35
- 5,200 PSI: 0.25
Max Speed (ft/sec): 3.0
Mating Surface Roughness - Ra (µm) - DYNAMIC: 0.1<>0.3
Mating Surface Roughness - Ra (µm) - STATIC: 0.8 MAX
Part Number Definition (Metric): PU-TDT (ROD DIAMETER)X(OD)X(HT)
Additional Part Number Definition (Metric): 90 X 98 X 11.5 = PU-TDT 90X98X11.5