Orifice accessories consists of orifice plates which is generally supplied to fit inside the bolt circle of existing customer flanges or as part of a complete orifice assembly ready for welding into on-site pipework. The most common type of flange is the weld neck. Other forms of flanges can be supplied like slip on and screwed. Assemblies consist of pairs of flanges, orifice plate, bolts, nuts, gaskets, jacking screws and plugs. The orifice line tubing is a special heavy wall black polyethylene line, designed for bubble-orifice installations.