초록 ▼

The invention relates to means and methods for rendering fire-safe, or more fire-safe, steel or like pipework which is lined with a plastic or like liner. At joints in such pipework, the liner is brought out over the flange face to form the actual seal. Consequently, the liner is vulnerable to fire

The invention relates to means and methods for rendering fire-safe, or more fire-safe, steel or like pipework which is lined with a plastic or like liner. At joints in such pipework, the liner is brought out over the flange face to form the actual seal. Consequently, the liner is vulnerable to fire or other forms of external heat at the joints. In accordance with the present invention, a metal ring is provided around the periphery of the liner at each joint to protect the liner from fire. The metal ring is not intended to provide a complete seal if the seal between the liners should fail, but is does prevent any large escape of the contents of the pipework. The ring may take various forms and may be, for example, a resilient ring of either U-section or M-section. Alternatively, the ring may be of flat-section and may slide on lips formed on inserts arranged between the flanges and the liners. These inserts may be arranged to provide the additional advantage of removing the need for special flange welding and machining.

대표청구항 ▼

In a joint between two pipe sections, each pipe section being of the type including an outer metal pipe and an inner liner of rubber or synthetic resin material, wherein metal jointing flanges are provided on the adjacent ends of the pipe section, and wherein each liner extends from the interior of

In a joint between two pipe sections, each pipe section being of the type including an outer metal pipe and an inner liner of rubber or synthetic resin material, wherein metal jointing flanges are provided on the adjacent ends of the pipe section, and wherein each liner extends from the interior of its associated pipe section radially outwardly to form a liner extension between portions of the respective flanges and terminating in generally annular surfaces, the joint including means for urging the flanges towards one another so that a seal is formed between the mating faces of the two liner extensions lying between the flange portions, the improvement comprising an annular metal ring between substantially planar, parallel faces of the jointing flanges and radially outwardly of the liner extensions, and first and second generally annular metal inserts, each of said inserts having a portion lying between one of said flanges and one of said liner extensions, each of said inserts further including an axially protruding peripheral lip forming sliding sealing contact with an inner surface of said annular ring such that the combination of said metal inserts and metal ring reduces leakage from the pipe joint in the event of failure of the seal between said liner extensions as a result of external fire.