Definition(s)
OP
Operating Pressure.
Source: ISO 14692-1:2017, Petroleum and natural gas industries — Glass-reinforced plastics (GRP) piping — Part 1: Vocabulary, symbols, applications and materials, Second Edition, August 2017. Global Standards
OP
Normal or anticipated standard internal pressure difference, i.e. internal minus external pressure, to be experienced by the pipe or piping system which should not exceed the design pressure.
Source: ISO 14692-1:2017, Petroleum and natural gas industries — Glass-reinforced plastics (GRP) piping — Part 1: Vocabulary, symbols, applications and materials, Second Edition, August 2017. Global Standards