Dumbbell-Shaped Sealing Ring

In the current hydraulic cylinder design, O-rings or O-ring + retaining ring combination are mainly used as static seals. However, this sealing solution has certain risks during assembly because the O-ring may be twisted and the position of the retaining ring may not be optimal. This solution also shows disadvantages in the case of pressure pulsation and the intrusion of dirt. In this case, dumbbell-shaped sealing ring can be used as an ideal substitute as a static hydraulic seal of a single original.

Product features and applications:

Technical Data

Pressure: up to 50MPa.

Temperature: -35℃...+110℃.

Material: Polyurethane.

Installation Requirements

(1) The installation chamfer C is selected according to the value of the groove depth W (mm)

When W<3; C≥3.

When W>3; C≥5.

(2) Surface finish          

(3) The dumbbell-shaped sealing ring has no leakage under the following test conditions and is very resistant to extrusion.

(4) Optimal sealing gap:

Cylinder bore - H8

Guide sleeve - g6

Since the seal is very resistant to extrusion, a radial sealing gap S of 0.2 mm can be achieved.

In low temperature use, deviations from the guide sleeve to the cylinder bore and piston rod should be avoided.

Installation Recommendations

Advantage

Compared with O-rings or O-ring + retaining ring combinations, dumbbell seals have the following advantages:

(1) Very resistant to twisting

(2) Easy to install

(3) Long service life

(4) High pressure resistance

Application

Dumbbell seals are commonly used in hydraulic cylinders, such as:

(1) Forklifts

(2) Construction machinery hydraulics

(3) Industrial hydraulics

(4) Machine tools

(5) Injection molding machines

(6) Hydraulic presses

(7) Cartridge valves