Working principle and design principle of safety valve
Safety valve operating principle
Safety valve is the boiler, pressure vessel and pressure pipe protection device, used to avoid pressure equipment in the pressure beyond the planning permission, and then protect the safety of equipment and its operation personnel.
Because the safety valve can not rely on any external power and action, so often as a device for the final pressure protection device. In this sense, it is not the role of other protective devices to replace.
When the pressure equipment in the medium pressure because of a certain reason and abnormal rise, reaching the preset value, the safety valve initiative to open, and then discharge, to avoid the pressure continued to rise. When the medium pressure due to the safety valve discharge and decline, reaching another reservation value, the valve and the initiative to seal off the media continued to discharge. When the medium pressure in the normal operating pressure, the valve to maintain the seal and seal.
Safety valve planning criteria
The planning of the goods is necessary to satisfy all the needs of the actual use of the user.
Under the premise of ensuring the practical application, the commodity should be the most economical (such as the selection, material and so on).
How to make the safety valve of the general function to reach the standard is the primary criterion for planning.
4 and many do type experiments on planning goods, to obtain functional parameters as planning data.
The accurate planning of spring stiffness, in order to match the structure of the internal parts of the more reasonable planning, the product easy to dismantle and repair.
The longer use life (including repair days).
Because of the use of safety valve of the medium is complicated, the overall can be summed up as three cases, that is, steam, gas and liquid (critical situation is a special case). Sometimes, planning personnel with in cold state experimental techniques, functional data obtained in the safety valve, but for heavy oil (asphalt) dielectric function and not necessarily ambition, planning personnel could not function experiment under the condition of various media, which makes plan of safety valve can not copy which forms of sophisticated goods, but according to the actual application of the different media, planning the spring stiffness appropriate, within a structure reasonable goods. Of course, the safety valve is the final product of the guidelines to allow users to get a satisfactory. But the shortcut of planning a good commodity, the first is still the accumulation of experience from the scene.