Structure design principle of fire ball valve
5 ball valve seat structure typical fire abroad professional production company common pipeline ball valve seat structure design of typical figure 9 - 12 shows, each seat structure fireproof structure design is reasonable, to ensure the seat piston effect of the sealing ring and the valve seat seal failure, valve seat leakage way at least. Figure 9 rubber sealing seat 1 to the left to the right in Figure 10 | rubber sealing seat 2 to the left to the right | Figure 11 rubber and plastic combined sealing seat to the left to the right in Figure 12 | plastic seat to the left to the right seat | fireproof structure design reasonable, can guarantee the way upstream pressure medium through the valve seat leakage at least fire, the best performance. In the design of fireproof structure of pipeline ball valve, the fire protection structure design of valve seat should be paid more attention to. The seat of fire with reasonable structure is the fundamental guarantee of fire safety in the pipeline valve in practical engineering, reasonable assessment of structural fire protection should be strictly in accordance with the API6FA/API607 standard fire test, test samples should not be sample makers, should be the verification institution with sampling, so as to ensure the rationality of the third party authentication and notarization of.
The purpose of fire protection structure design of valve seat is:(1) effective guarantee in the fire accident, the upstream pressure medium as little as possible into the body cavity through the valve seat, thereby causing internal leakage and leakage. Ensure that fire accidents are not expanded by fire before the firemen arrive at the scene of the accident. After the firemen arrive at the scene, fire equipment can be used to quickly suppress the fire and eliminate fire accidents.(2) to make the structure of the product meets API6D specifications. Fire proof can be obtained through fire test.Fireproof design of valve seat:Set graphite in metal fire valve seat and valve body sealing rings; sealing set fireproof metal in the metal valve seat and ball room. The structure is shown in Figures 1 and 2.
The fire ball is fixed ball structure, the upper end of the main seal seal, the seal has the function of DBB, in good condition, the valve in the fully open or fully closed state, the cavity in the outfall or vent to observe the upstream seat leaks. Pipeline ball valve in normal use, the middle chamber without pressure. In the case of fire accidents, a reasonable design of the fire protection structure of the valve seat can slow down the progress of the upstream pressure medium into the middle cavity, and avoid the leakage and leakage of the medium caused by the boosting of the middle cavity. The valve seat with good fire protection design is an active measure to ensure the safety and fire resistance of the pipeline ball valve.The fireproof structure design, the design of the seat structure fire is the key, the seat of the fire performance is good, in the fire accident condition, fire structure design of the pressure between the body and the stem structure, reduce the fire around the body.
