2014年12月30日星期二

Gas pipeline valve characteristics


    With the development of the natural gas pipeline industry, the amount of natural gas pipeline Copper Gas Valves increasing natural gas pipeline valves and general valves are different. Specifically the following points:
     1, the material
     Because of the natural gas pipeline transportation desulfurization ago contains a lot of hydrogen sulfide (which is a highly toxic and corrosive gases, it reacts iron sulfide and iron, can be flaky peeling, pitting wear machinery). Even after gas desulfurization process and other processes, there are still remnants of hydrogen sulfide. Therefore, selection must be selected pipeline valve corrosion resistance to sulfur material.
    2, leakage
    Most of the natural gas pipeline network built on the edge of the city, unlike the general operation and management of the factory, workers often have the operation, maintenance and inspection. Average city gas pipeline are hundreds of kilometers, only regular patrols, inspection, and sometimes complicated pipeline through the region, media leaks could result in serious fires. Especially from the city closer to the pipeline, to prevent leakage of the Gas Heater Control Valve is particularly important.
    Gas valve leakage requirements are very strict, usually buried and more important valves are used all-welded body structure. In order to ensure the sealing performance of pipeline valves require valve with excellent corrosion resistance, wear resistance, self-lubrication and elasticity. In recent years, the development of polymer materials pipeline Gas Grill Valves seal material selection provides a broad selection of the world, such as Teflon, nylon, acrylonitrile-butadiene rubber (NBR), a special synthetic rubber (VITON) as the.

2014年12月26日星期五

Combination of surface leakage valve body


   Refers to the combination of upper and lower body at the surface leakage, leakage of the main reasons for this are the following aspects:
   First, the combination of bolt tightening force plane is not enough or tight side, causing a bad combination of surface sealing. Elimination method is to adjust the bolt tightening force, we must act upon the bolts diagonally to tight manner, preferably tight side edges around gap measure, tighten the bolts to tighten stops, and combined with a gap around the face unanimously.
   Second, the combination of the tooth surface oven safety valve body gasket does not meet the criteria. For example, there is a slight radial profile gasket grooves, parallel to the difference, too sharp or too sloping tooth defects can cause seal failure. So that the valve combination of surface leakage. In the maintenance of the good quality spare parts, the use of standard tooth profile gasket can avoid this phenomenon.
   Third, the valve body joint surface flatness poor live or hard pad impurities cause seal failure. As the body of the method combined with the flatness of the surface of the body caused by bad combination of surface leakage, eliminate
Is the valve until the disintegration of the joint surface reground meet quality standards. Due to impurities caused by seal failure pad to live in the Burner Valves assembly carefully cleaning the joint surface to avoid falling into impurity.

2014年12月22日星期一

The most common failure safety valve?


     
   The Natural Gas Safety Valve is a very important protection valves, are widely used in various pressure vessels and piping systems, when the compression pressure in the system exceeds a predetermined value, it is automatically opened, the excess medium discharged to the atmosphere go to ensure the safety of pressure vessels and piping systems operation, prevent accidents, and when the system pressure back down to the working pressure or slightly lower than the working pressure can automatically shut down. Reliable safety valve work is directly related to the equipment and personal safety, it must be given attention.
    a common cause of valve failure analysis and solutions
    safety valve leakage
   Under normal operating pressure equipment, gas stove safety valve and valve seat sealing surface took place more than allowed levels of leakage, valve leakage will not only cause loss of media. In addition, the media will continue to leak so hard sealing material destruction, but the common safety valve sealing surface is metal on metal, although strive to do is smooth, but to do with pressure situations in the media to absolutely no leakage is very difficult. Therefore, the working medium is steam safety valve at a predetermined pressure value, if the outlet end of the invisible, it can not find a leak, sealing performance is considered acceptable.

2014年12月18日星期四

Stove safety valve selection and installation considerations?



      Many customers in the choice of boiler safety gas stove valves, do not know the selection, resulting in a great security risk. And in the course, I do not know the maintenance and installation of key technologies, also faces
Great danger, especially for higher safety factor requirements for boilers, we now introduce to you on this issue and technologies:

     (l) Rated evaporation is greater than 0.5t / h boiler, installed at least two safety valves: Rated evaporation is less than or equal to 0.5t / h boiler, at least install a safety valve. Separable economizer outlet
At the outlet of the steam superheater safety valve must be installed.
   
     (2) safety valve should be installed vertically at the highest position in the pot business, collection boxes. Between the valve and the drum or header shall be equipped with access steam outlet pipe and valves.
   
     (3) there must be a Safety Valve Burner Valve to prevent the hammer leveraged their own mobile devices and limit leverage deviant guides, spring safety valve should enhance handle and prevent casual twist adjustment screw devices.
   
     (4) For the rated steam pressure less than or equal to 3.82MPa boiler safety valve throat diameter of not less than 25mm: the rated boiler steam pressure is greater than 3.82MPa, safety valve throat diameter of not less than
20mm.
   
      (5) connected to the safety valve and the boiler pipe, its cross-sectional area not less than the cross-sectional area of the valve imported. If several valves installed together with the short tube in a drum directly connected via a short tube
Channel cross-sectional area should not step on all exhaust valve area 1.25 times.
   
(6) general safety valve should be installed in the exhaust pipe, exhaust pipe should be through a safe place, and there is sufficient cross-sectional area, to ensure the smooth flow of the exhaust. Bottom valve exhaust pipe should have received a place of safety posturing sparse
Pipe, the exhaust pipe and the installation of drainage Range Dual Safety Valve are not allowed.