Spring-Orings™ – ideal for Cryogenic applications
Spring Orings are ideal for sealing at extremely low temperatures where traditional elastomers suffer from brittleness. Low compression sets allow effective sealing as low as -250C in Cryogenic applications.
Industries including pharmaceutical, medical and chemical processing all encounter low temperature cryogenic conditions. They experience situations where it is very difficult to achieve effective liquid or gas sealing.
Even elastomers that we consider to be good at low temperatures (i.e. Silicone or Fluorosilicone) can quickly become brittle and lose their ability to provide resilience. This results in premature leakage.
Spring Orings utilise a precision rolled flat strip spring in 301 stainless steel (AMS 5519N). These seals are specially formed to energize a seamless jacket of Fluoropolymer (FEP or PFA). This assembly provides effective sealing in face type applications as low as -250°C.
Spring Orings should have a split housing design that does not require the part to stretch on fitting. A small amount of stretch can be tolerated but never greater than 4% of the seal’s inside diameter. Standard static groove conditions apply with a minimum surface finish of 20 micro-inches.
We recommend a vented jacket on Spring Orings where pressures exceed 60 bar. Vents are a series of small holes in the wall of the encapsulating jacket that prevent any pressure rupture.
• FEP / Spring O-Ring: 250°C to +204°C (-420°F to + 428°F)
• PFA / Spring O-Ring: 250°C to +260°C (-420°F to +500°F)
Lead times are approximately 14 to 21 days for the standard range. Prices (on application) are very reasonable considering the technical merits of this product.
We welcome any queries you have regarding this product. Please contact our Product Support team with any further requests.
Dimensions & Availability
The following chart provides dimensions of standard product that is readily available. Specials are of course possible if the cost of setting up is acceptable, apply in each instance to our sales office. Also shown is the maximum amount of compression recommended for successful sealing which is lighter than conventional O-rings.
CS Ø mm
CS tolerance ±
Min Inside Ø possible/mm
Max Inside Ø possible/mm
|2.62||0.13||0.61||15.24||No Upper Limit|
|2.79||0.13||0.64||15.24||No Upper Limit|
|3.00||0.13||0.64||19.05||No Upper Limit|
|3.18||0.15||0.64||19.05||No Upper Limit|
|3.53||0.15||0.64||19.05||No Upper Limit|
|3.76||0.15||0.69||24.13||No Upper Limit|
|3.99||0.18||0.69||29.21||No Upper Limit|
|4.50||0.18||0.79||38.10||No Upper Limit|
|5.00||0.20||0.89||38.10||No Upper Limit|
|5.33||0.20||0.97||38.10||No Upper Limit|
|5.72||0.20||1.02||38.10||No Upper Limit|
|6.35||0.25||1.09||63.50||No Upper Limit|
|6.99||0.25||1.09||63.50||No Upper Limit|
|7.49||0.25||1.19||69.85||No Upper Limit|
|8.00||0.30||1.27||76.20||No Upper Limit|
|8.40||0.30||1.45||101.60||No Upper Limit|
The Spring-Oring should have a split housing design that does not require the stretch of the part on fitting. A small amount of stretch can be tolerated but never greater than 4% of the seals inside diameter. Standard static groove conditions apply with a minimum surface finish of 20 micro-inches.
For pressures greater than 60 bar we recommend that the jacket of the Spring-Oring is vented. This is a series of small holes through the wall of the encapsulating jacket and prevent any pressure rupture.
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