R900529572 FDR5 DR1-14/55Y S037 Rexroth Safety Valve Concrete Pump Truck Spare Parts

Product Description/Features:
The safety valve is a special valve that is normally closed under the action of external force, and when the medium pressure in the equipment or pipeline rises beyond the specified value, the medium is discharged outside the system to prevent the medium pressure in the pipeline or equipment from exceeding the specified value. Safety valve is an automatic valve, mainly used in boilers, pressure vessels and pipelines, control pressure does not exceed the specified value, personal safety and equipment operation plays an important role in protecting. The injection safety valve must be tested before it can be used.

According to its overall structure and the different loading mechanism can be divided into weight lever type, spring type and pulse type three.
1. Weight lever safety valve
Weight lever safety valve is the use of weight and lever to balance the force acting on the disc. According to the lever principle, it can use a smaller weight to obtain a larger force through the increase of the lever, and adjust the opening pressure of the safety valve by moving the position of the weight (or changing the mass of the weight).
The weight lever safety valve is simple in structure, easy to adjust and more accurate, the added load will not increase due to the rise of the valve disc, suitable for high temperature occasions, used in the past is more common, especially used in boilers and high temperature pressure vessels. However, the structure of the heavy weight lever safety valve is relatively heavy, and the loading mechanism is easy to vibrate, and often leaks due to vibration; Its return pressure is low, it is not easy to close and keep tight after opening.
2. Spring micro-opening safety valve
The spring micro-opening safety valve uses the force of the compression spring to balance the force acting on the valve disc. The compression of the spiral coil spring can be adjusted by turning the adjusting nut on it, and the opening (setting) pressure of the safety valve can be corrected according to the need of this structure. Spring micro-lift safety valve structure is light and compact, the sensitivity is relatively high, the installation position is not limited, and because of the sensitivity to vibration is small, it can be used on mobile pressure vessels. The disadvantage of this safety valve is that the load added will change with the opening of the valve, that is, with the rise of the valve disc, the compression of the spring increases, and the force acting on the valve disc also increases. This is not conducive to the rapid opening of the safety valve. In addition, the spring on the valve will reduce the elasticity due to the long-term effect of high temperature. When used on containers with higher temperatures, it is often necessary to consider the thermal insulation or heat dissipation of the spring, which makes the structure complicated.
3. Pulse type safety valve
The impulse type safety valve is composed of a main valve and an auxiliary valve, and the main valve is driven by the pulse action of the auxiliary valve. Its structure is complex, and it is usually only suitable for boilers and pressure vessels with a large amount of safe leakage.
Among the above three forms of safety valves, the spring type safety valve is more commonly used.
By medium
According to the different medium emission mode, the safety valve can be divided into three kinds: fully closed, semi-closed and open.
1. Fully closed safety valve
When the fully enclosed safety valve exhausts, the gas is all discharged through the exhaust pipe, and the medium can not leak between the outside, mainly used for the medium is toxic. A container for flammable gases.
2. Semi-enclosed safety valve
Part of the gas discharged by the semi-closed safety valve is through the exhaust pipe, and a part is leaked from the gap between the valve cover and the valve stem, which is mostly used for the medium of the gas container that does not pollute the environment.
3. Open safety valve
The valve cover of the open safety valve is open, so that the spring chamber is communicated with the atmosphere, which is conducive to reducing the temperature of the spring, mainly suitable for the medium of steam, and the container of high temperature gases that do not pollute the atmosphere.
Open by disc
According to the maximum height of the valve flap opened and the ratio of the diameter of the safety valve, the safety valve can be divided into two kinds: spring micro-open closed high-pressure safety valve and spring full open safety valve.
1. Spring micro-open closed high pressure safety valve
The opening height of the micro-opening safety valve is less than 1/4 of the diameter of the flow channel, usually 1/40 to 1/20 of the diameter of the flow channel. The action process of the micro-lift safety valve is proportional, mainly used in liquid situations, and sometimes used in gas situations with small emissions.
2. Spring full open safety valve
The opening height of the fully opened safety valve is greater than or equal to 1/4 of the diameter of the flow path. The discharge area of the full-lift safety valve is the minimum cross-sectional area of the seat throat. Its action process is a two-stage action type, must use a lifting mechanism to achieve full opening, full opening safety valve is mainly used for gas medium occasions.
3. Middle lift safety valve
The opening height is between the micro opening and the full opening. It can be made into two stages of action, but also can be made into proportional action.
According to the principle of action
According to the principle of action, it can be divided into direct acting safety valve and non-direct acting safety valve.
1. Direct acting safety valve
The direct-acting safety valve is opened under the direct action of the working medium, that is, it relies on the role of the working medium pressure to overcome the mechanical load of the loading mechanism added to the valve disc, so that the valve is opened. The safety valve has the advantages of simple structure, quick action and good reliability. However, because it relies on structural loading, its load size is limited, and it can not be used in high-pressure and large-caliber occasions.
2. Non-direct acting safety valve
Such safety valves can be divided into pilot type safety valves and safety valves with power auxiliary devices.
Pilot operated safety valve is driven or controlled by the medium discharged from the pilot valve. The pilot valve itself is a direct acting safety valve, and sometimes other forms of valves are used. Pilot operated safety valve is suitable for high pressure, large diameter occasions. The main valve of the pilot safety valve can also be designed to rely on the working medium to seal the form, or the disc can be applied to a much larger mechanical load than the direct acting safety valve, so it has good sealing performance. At the same time, its movements are rarely affected by back pressure. The disadvantage of this safety valve is that its reliability is related to the main valve and the pilot valve, and the action is not as fast and reliable as the direct-acting safety valve, and the structure is more complex.
The safety valve with power assist is a power assist device that forces the safety valve to open below normal opening pressure. This safety valve is suitable for occasions where the opening pressure is very close to the working pressure, or where the safety valve needs to be opened regularly to check or blow out the adhesive and frozen media. At the same time, it also provides a means of forcing the safety valve to open in an emergency.
Adjust the points according to pressure
According to whether the pressure can be adjusted, it can be divided into fixed non-adjustable safety valves and adjustable safety valves
1. The pressure value of the fixed non-adjustable safety valve has been set before the factory and cannot be changed when used. It is commonly used in central air conditioning, boiler wall hanging furnace, solar energy and other systems, such as S10 series safety valve.
2. Adjustable safety valve starting pressure can be arbitrarily set with the different needs of users in a certain range, often used in the system protection pressure needs to change frequently occasions, such as S10 series safety valve, but the price is generally relatively high.
According to the operating temperature
1. The normal temperature safety valve is generally only installed in the HVAC, air conditioning or water system temperature 110℃ safety valve, such as 0480 safety valve.
2. High temperature safety valve refers to the safety valve that is specially used in the solar energy system and the mold temperature machine system, such as the 1831 series safety valve.

ABOUT COMPANY:

Changsha HuaYi Technology Co., LTD.,