News

New products

  • Pure Expanded Graphite Gasket
    Pure Expanded Graphite Gasket

    High quality Pure Expanded Graphite Gasket from professional China Pure Expanded Graphite Gasket manufacturer - Ningbo Kaxite Sealing Materials Co., Ltd.

  • Graphite Gasket Reinforced With Metal Foil
    Graphite Gasket Reinforced With Metal Foil

    High quality Graphite Gasket Reinforced With Metal Foil from professional China Graphite Gasket Reinforced With Metal Foil manufacturer - Ningbo Kaxite Sealing Materials Co., Ltd.

  • Graphite gasket reinforced with metal mesh
    Graphite gasket reinforced with metal mesh

    High quality Graphite gasket reinforced with metal mesh from professional China Graphite gasket reinforced with metal mesh manufacturer - Ningbo Kaxite Sealing Materials Co., Ltd.

  • Tanged Metal Reinforced Graphite Gasket
    Tanged Metal Reinforced Graphite Gasket

    High quality Tanged Metal Reinforced Graphite Gasket from professional China Tanged Metal Reinforced Graphite Gasket manufacturer - Ningbo Kaxite Sealing Materials Co., Ltd.

  • Lens Ring Joint Gasket
    Lens Ring Joint Gasket

    High quality Lens Ring Joint Gasket from professional China Lens Ring Joint Gasket manufacturer - Ningbo Kaxite Sealing Materials Co., Ltd.

News

Gasket Reasons for failure

HIT:14    DATE:2015-3-25

Uneven distributed pressing force

Uneven pressing force is caused by a variety of factors, first is the human factor: asymmetric construction of the preload bolt, this factor can eliminate construction; theory on the flange pressed, the sealing surface is absolutely parallel to the practice, however, the centerline of a pipeline can not be absolutely concentric, and thus tighten the bolts on the flange moment, so that the flange discontinuity. Asymmetrical connection, the sealing surface more or less deformed, so that sealed the pressing force is reduced, the running load, prone to leakage. Third, the density of bolt arrangement on the pressure distribution more obvious impact, the closer the bolts, the more uniform the pressure.

Stress relaxation and torque loss

Tighten bolts on the flange, due to the vibration of the bodies, the temperature increased or decreased and other factors, the working process of the spiral wound gaskets stress relaxation, the bolt tension will be gradually decreased, resulting in loss of torque, causing a leak. In general, long bolts, the remnants of the torque, the smaller the diameter the more advantageous to prevent the loss of torque, with long, thin bolt is an effective way to prevent torque loss. Heating a certain period of time to make it stretch the bolt, and then to maintain a given torque, is very effective to prevent the loss of torque. There is a gasket is thinner and smaller the loss of torque. In addition to prevent the strong vibration of the machine and the pipe itself, and exclude the impact of adjacent equipment vibration, the impact of the sealing surface is not meaningless, not to beat the bolts tightened, can prevent the loss of torque.

Surface not smooth

It is important to make the sealing finish properly otherwise it will cause leakage.

Temperature

Flanged leak often occurs in the cooling, because the cooling rate of cooling when the flange and bolts do not After cooling, the pressing force of the metal gaskets stress relaxation, combined with the cold contraction of the pipe, resulting in toward the bolt tensile direction force, this force will lead to leaks in, where the low-temperature media occasions when gasket should be noted: 1) low temperature flexible gasket; 2) shim thickness should be as much as possible to take a small flange gap as small as possible; 3) high strength bolts, so that the strain is small.