Comparison of PTFE Spring Energized Seals Between Oring and U-ring
6. Working temperature
O-ring
There will be some differences according to different rubber materials, but basically 0-70°C is the best working range. The working range of some rubbers will be larger under special working conditions, such as silicone rubber, which can only withstand 100 °C in water. but can reach 210°C in air.
U-seal
The normal operating temperature of it is -30 to +110°C.
PTFE Spring Energized Seals
Operating temperature -200 to +250°C. (Depending on the material of the jacket, the operating temperature range of the spring is much larger than the jacket)
7. Extrusion gap and failure pressures
O-ring
It's based on the hardness of the materials. The compression resistance and extrusion resistance are quite different for different hardness. Generally, if the pressure is greater than 5MPa, a back-up ring needs to be installed, otherwise extrusion damage may occur. It is better that the extrusion gap is less than 0.1 during installation.
U-seal
It's based on the hardness of the materials. The compression resistance and extrusion resistance are quite different for different hardness. Generally, if the pressure is greater than 15MPa, a retaining ring needs to be installed, otherwise extrusion damage may occur. It is better that the extrusion gap is less than 0.2 during installation.
PTFE Spring Energized Seals
The single bearing pressure can reach 20-50MPa. If a special retaining ring is installed, the pressure can be more than 100MPa. When the installation groove is the same as the O-ring, the extrusion gap can be 2-3 times that of the O-ring seal, which greatly reduces the manufacturing cost.
8. Main sealing form
O-ring
The main sealing form is static sealing, and few of them can be used for pneumatic low pressure sealing.
U-seal
The main sealing form is dynamic sealing, and few of them can be used for static sealing.
PTFE Spring Energized Seals
The main sealing form is dynamic sealing, and few of them can be used for static sealing.
9. Service life
O-ring
If it is compatible with the medium, under the normal temperature and low pressure, not contact with light, the service life could be long for static, otherwise it will be much shorter, generally less than 2 years. The life of the dynamic seal is generally not long, which is mainly determined by the pressure, the roughness of the contact surface and the lubrication condition.
Not available for dry rubbing
U-seal
It depends on the following factors under specific working conditions: working temperature, moving speed, working medium, and roughness of the contact surface.
Not available for dry rubbing
PTFE Spring Energized Seals
Under the same working conditions, it is 10 to 100 times more than Oring and Uring.
Can be used for dry rubbing.
10. Cost-effective
O-ring
In the case of one-time installation and use, the cost-effectiveness has unparalleled advantages, but if the working conditions are special: working medium, high temperature, high pressure, large gap, poor lubrication, required working life, etc., the cost-effectiveness is not ideal, although the seal It is very cheap in itself, but the cost of repeated disassembly, installation, leakage, etc. is high.
U-seal
When reciprocating at low pressure and low speed at room temperature, it is cost-effective, and it is not ideal for use in high temperature, high speed or high pressure conditions.
PTFE Spring Energized Seals
Because the price is more expensive than the U-shaped ring, it may not be cost-effective for the working conditions with low general requirements, but if the working conditions have special working medium and require low friction, high temperature, high speed or high pressure, etc., or have requirements for service life , It is better to use the PTFE Spring Energized Seals