Abstract: An orifice seal is shown of the type adapted to be inserted into an orifice meter tube for determining fluid velocity within the tube. The orifice seal includes a resilient seal ring which is adapted to be received about a circumferential region of the orifice plate. The seal ring has circumferential grooves formed on either side of an orifice plate channel. The grooves are formed between inner and outer resilient lips of the seal ring. The inner lips of each of the circumferential grooves is arranged to overlie the circumferential region of the orifice plate when the plate is in place to retain the orifice plate within the seal ring. A U-cup spring located within each of the circumferential grooves resists the deformation of the groove lips by pressure acting on the orifice plate to prevent cold flow of the seal material.