Update: UK centre sheds light on oil & gas elastomers

London – New insights into the performance of seals, hoses, joints, and other elastomer components used in the oil & gas industry are now emerging via a test technology developed atElements Materials Technology (EMT) in Hitchin, UK.

The research centre has come up with new testing methods to study the effects of extreme temperatures and pressures on elastomers, explains Glyn Morgan, EMT oil and gas sector manager told an IoM3 seminar on elastomers in extreme environments, held 12 Dec in London.

As part of this work, EMT has developed two sapphire-windowed pressure vessels that enable scientists to see the changes in elastomers as they happened, Morgan said at the event, sponsored by the Rubber in Engineering Group (RIEG).

“To see what is happening to a seal as it functions or leaks ‘in the dark’ is worth a thousand hours,” said Morgan, who went on to report findings from a series of tests on elastomeric seals.

“One of the pressured vessels had an O-ring squashed and sealed against one window and one had windows at both ends to observe material samples,” Morgan added.

After a series of tests, said Morgan, our observations showed that pressurised seals remain ‘locked’ in their energised shape when cooled, even when leakage occurs – no movement or loss of contact area is observed.

Without pressure, however, there is a reduction in contact width during cooling but this does not reduce to zero, Morgan noted. The team, he said also saw that when cold, unpressurised seals function (re-seal) when the temperature allows low-level movement at the seal ID.

Morgan, concluded that “seal movement under the influence of applied pressure is a primary factor in sealing capability [and] that glass transition remained a reliable, albeit conservative, basis for seal selection, provided that significant thermal ageing does not occur during service.”