The Globe Valve stem shaft and the Globe Valve seat sealing surface perpendicular to the stem open or close the stroke is relatively short, the Globe Valve Globe Valve Globe Valve once in the open state, and its Globe Valve seat and sealing surface between the no longer contact, And has a very reliable cutting action, making the cut-off Globe Valve products suitable for the media as a cut or adjust and throttling use. Once the stop Globe Valve is in the open state, its Globe Valve seat and the Globe Valve seal surface is no longer between the contact, so the sealing Globe Valve sealing surface mechanical wear less. Since most of the Globe Valve seat and the Globe Valve flap are easier to repair or replace the sealing element, it is not necessary to remove the entire Globe Valve from the pipeline, which is suitable for the welding of Globe Valves and pipelines. The flow direction of the medium through such a Globe Valve has changed, so the flow resistance of the Globe Valve is higher than other Globe Valves.
The most obvious advantage of the cut-off Globe Valve is that during the opening and closing process, the friction between the Globe Valve flap and the sealing surface of the Globe Valve body is smaller than that of the gate Globe Valve. The opening height of the shut-off Globe Valve is generally only 1/4 of the diameter of the Globe Valve seat passage, and therefore is much smaller than the gate Globe Valve. Usually in the Globe Valve body and the Globe Valve only one sealing surface, so the manufacturing process is better, easy to repair.
The principle of selection of the Globe Valve is:
1 high temperature, high pressure medium pipe or device should use the cut-off Globe Valve. Such as thermal power plants, nuclear power plants, petrochemical system of high temperature, high pressure pipeline.
2 cut-off Globe Valve on the pipeline on the flow resistance on the strict management of the pipeline. That is, the pressure loss is not considered much place.
3 small Globe Valve can choose needle, instrument Globe Valve, sampling Globe Valve, pressure needle and so on.
4 flow adjustment or pressure regulation, but the regulation accuracy is not high, and the pipe diameter is relatively small, such as the nominal through the ≤ 50mm on the pipeline, should use the cut-off Globe Valve.
5 synthetic industrial production of small chemical fertilizer and large chemical fertilizer should use the nominal pressure PN160 nominal pressure 16MPa or PN320 nominal pressure 32MPa high pressure angle Globe Valve or high pressure angle throttle.
6 Alumina Bayer process in the production of desilicon workshop, easy to coke on the pipeline, easy to use the Globe Valve body separately, the seat can be located, carbide seal of the DC-type cut-off Globe Valve or DC throttle.
7 urban construction in the water supply, heating works, the nominal through the smaller pipeline, the choice of cut-off Globe Valve, balance Globe Valve or plunger Globe Valve, such as the nominal through less than 150mm on the pipeline.
Commonly used cut-off Globe Valve are the following:
1 angle cut-off Globe Valve: the angle of the Globe Valve, the fluid only need to change the direction, so that the pressure drop through the Globe Valve than the conventional structure of the cut-off Globe Valve.
2 DC cut-off Globe Valve: In the DC or Y-shaped Globe Valve, the Globe Valve body flow channel and the main channel into a slash, so that the flow of the degree of damage than the conventional cut-off Globe Valve is small, and thus through the Globe Valve pressure loss corresponding Small.
3 plunger stop Globe Valve: This type of cut-off Globe Valve is a variant of the conventional shut-off Globe Valve. In the Globe Valve, the Globe Valve and Globe Valve seat is usually based on the principle of the design of the plunger. The disc is polished and the plunger is connected to the stem, and the seal is achieved by two elastic seals mounted on the plunger. The two resilient seals are separated by a collar and are pressed against the seal around the plunger by the load applied to the bonnet by the bonnet nut. The elastic seal can be replaced and can be made of a wide variety of materials. The Globe Valve is mainly used for "open" or "off", but with a specially designed plunger or special collar, which can also be used to adjust the flow The