To teach the appropriate application of valves to reduce the specific methods of common valve failures various general valves and valve induction

To teach the appropriate application of valves to reduce the specific methods of common valve failures various general valves and valve induction

       Because a variety of valves in the chiller system software play the role of adjusting and controlling the flow of steam and liquid. Therefore, the quality of its product plays a vital role in the normal operation of the industrial chiller system software. At the same time, the operation and use of the valve is not careful to lead to leakage (including exposure and leakage), the valve deformation, bending, cracking, etc., are affecting the normal operation of the operating system. Some common valve failures are usually the result of incorrect operation. Therefore, proper application of valves is a strong assurance to reduce common valve failures.

Because a variety of valves in the chiller system software play the role of adjusting and controlling the flow of steam and liquid. Therefore, the quality of its product plays a vital role in the normal operation of the industrial chiller system software. At the same time, the operation and use of the valve is not careful to lead to leakage (including exposure and leakage), the valve deformation, bending, cracking, etc., are affecting the normal operation of the operating system. Some common valve failures are usually the result of incorrect operation. As a larger opening valve, without each other during the handover job handover clear, took over after the found according to the data traffic is not enough, mistakenly assume that the valve does not open or open degree is insufficient, to carry out the open again, as in specialty started to extend the arm And too hard and the valve rod deformation, bend, rupture, etc. Therefore, proper application of valves is a strong assurance to reduce common valve failures.
① When the valve is opened and closed, it is strictly forbidden to exert too much force and extend the moment arm.
(2) When the valve is in a larger opening degree, the handwheel should be rotated 1 ~ 2 times to prevent the opening of all mistakenly thought closed and carry out the actual operation.
(3) the valve stem sealing filling material in the room filling material is not suitable for too much or too little, it is advisable to screw the cap basically can be rushed down, at the same time should maintain a certain amount of grease in the filling material room. In order to prevent leakage along the stem, reduce dry friction, avoid stem bite, and then make the valve open and close easily. The valve that is not often used can be opened and closed on time under the condition of system optimization.
(4) the valve closes, if one can not turn off the sealed, the valve core is to improve some, such as the valve handwheel to open the azimuth rotating circle of 1 ~ 2), rapid flow of medium in the system of valve core and high pressure gate valves for flushing, to remove the high pressure gate valves and valve heart of granular particles, after hard locked can once again.
⑤ The handwheel on the valve should not be taken to be used for it, so as to prevent it from being found in emergency application. For all normal operation or in the fluorine valve after shutdown, the sealing cap should be tightened to prevent refrigerant from leaking out of the valve stem.
In general, other special tools (such as the wrench) can not be used to replace the valve handwheel to carry out the actual operation.
If the valve needs to be disassembled and repaired, the first end of the valve should be disassembled and disconnected from the system software, that is, turn off the relevant valve, and then open the refrigeration compressor, the valve and the related connection of the pipeline refrigerant as far as possible. At the same time, prepare for disassembly and assembly in advance (for example, wear rubber gloves, prepare gas masks for ammonia system software, and open the centrifugal fan for safety accidents to carry out natural ventilation). Disassembly should not deal with the single flow valve, to avoid refrigerant vapor break injury, in the disassembly of the single flow valve nut, the first should be symmetrical loose but do not have to get, such as single flow valve loose, no refrigerant break when unloading, if there is still refrigerant break, the single flow valve should still be tightened, find out the reason and remove again after disassembly.
All kinds of universal valves and valves are summarized
A, valves
Ball valve, open and close parts (ball) driven by the valve stem, and around the center line of the valve for rotary activities of the valve.
Features:
1, wear resistance: because the core of hard sealing ball valve is carbon steel spray welding, the sealing ring is carbon steel spray welding, so hard sealing ball valve is not easy to cause great damage when the power switch. (It has an intensity index of 65-70) :
2, good sealing function: because the sealing of hard sealing ball valve is the use of human grinding, until the valve core and sealing ring completely consistent can be applied. So his airtight nature makes sense.
3, power switch light: because the bottom of the sealing ring of the hard sealing ball valve uses torsion spring to make the sealing ring and valve core tightly held together, so the power switch is very light when the external energy exceeds the pretightening force of the torsion spring.
4, long service life: has been widely used in crude oil, chemical plants, power generation, paper industry, nuclear energy, airlines, rockets and other units, and everyone’s daily life.
Advantage:
Advantages:
1, liquid obstruction is small, and its resistance coefficient is the same as the pipe of the same size.
2, simple structure, small size, light weight.
3, close to the spectrum, and the valve surface raw materials used plastic, good airtightness, in the ultrafiltration device has also been used.
4. Practical operation is convenient, fast opening and closing, only need to rotate 90° from opening to closing, which is conducive to remote operation.
5, convenient maintenance, simple ball valve structure, sealing ring is generally all action, disassembly and replacement are very convenient.
6, wide application, pipe diameter from small to a few millimeters, large to how many meters, high vacuum pump or high pressure can be used.
Two, stop valve
(1) Fire gate valve: rotate the hand wheel to raise or lower the porous plate connected with the valve stem according to the advance or withdrawal of the screw teeth of the hand wheel and the valve stem, so as to enable and close the function.
Fire gate valves have the following advantages:
1, the liquid obstruction is small, the surface is washed and etched by the medium.
2, open and close more effort.
3, medium inflow is not limited, no turbulence, no reduction of pressure.
4, simple body, short structure size, good production and manufacturing process performance, wide application field.
The defects of the fire gate valve are as follows:
1, the middle of the surface is easy to cause erosion and abrasion, maintenance is very difficult.
2, the size is relatively large, the opening must be a certain indoor space, long opening and closing time.
3, the structure is complex.
(two) dark rod gate valve: also called rotary rod globe valve (also called dark rod wedge type gate valve). The stem nut is arranged on the gate valve, and the handwheel rotates to push the stem to rotate, and the gate valve is raised. Usually there is a trapezoidal thread at the bottom of the stem. According to the valve bottom screw teeth and the guide groove on the piston valve, the rotation activity becomes uniform linear motion, that is, the actual operating torque becomes the actual operating driving force.
Three, disc valve: butterfly valve, also known as flap hook valve, is a simple structure of the regulating valve, can be used as a low voltage pipeline medium switch adjustment disc valve is to turn off the parts (piston valve or butterfly plate) for the disc, tightly around the valve shaft to open and close a valve.
Four, stop valve: check valve refers to the flow of the medium itself and fully automatic open and close piston valve, used to avoid the medium countercurrent valve, also known as the reverse valve, throttle valve, reverse valve, and back pressure valve. Check valve belongs to a kind of automatic valve, its key function is to avoid the medium countercurrent, to avoid the pump and promote the motor to turn over, and its utensils medium release.
Five, valve: safety valve is the open and closed parts under the external force is located in the normally closed situation, when the medium pressure in the facility or pipeline rises beyond the standard value, according to the system to prevent the medium pressure in the pipeline or facilities beyond the specified data of the unique valve. Valve belongs to self valve class, mainly used in heating furnace, pressure vessel and pipeline, operating pressure does not exceed the standard value, for life safety and facilities operation of the main guarantee effect.
Six, low leakage and high sealing valve: the role of low leakage and high sealing valve: it is to avoid the system software because of the accumulation of steam leakage caused by the wrong operation of the system software and installed in the pipeline valve. It is installed in the startup pipeline, usually in the open situation, only in the inlet pressure to set the pressure to shut down, its key function is to remove leakage because of pneumatic valve
Seven, pressure regulating valve
(a) proportional pressure reducing valve: the opening of the pilot valve is all by using the top adjustment anchor bolt clockwise, so that the elasticity caused by the torsion spring contraction, so that the pilot valve pulse damper dent down, the effect of the force on the pilot valve crankshaft, so that the offset down to open the pilot valve. When the pilot valve is opened, the upstream and downstream steam into the A cavity of the steam pipe section through the α safety channel (steam adjustment safety channel), through the pilot valve into the pilot valve ring cavity, from the β safety channel immediately sent to the chest and abdominal cavity of the piston rod cylinder below. Under the continuous supply of vapor in chamber A, the pressure rises continuously, which promotes the piston rod to slide and open the distribution valve. At this time, an endless stream of vapor flows from chamber A to chamber B. When the load in chamber B of the inlet and outlet section of the middle and downstream reaches, the excess steam makes the pressure in chamber B continue to rise. Continuous rising pressure according to the safety channel γ (pressure magnetic induction safety channel) feedback to the pilot valve pulse damper chamber, the pilot valve diaphragm upward convex, get rid of the upper end of the adjustment of the torsion spring pressure, the pilot valve is small or shut down. Further, turn down or turn off the vapor source from the upstream and downstream α safe passage. When the thoracic and abdominal pressure of the piston rod cylinder is reduced, the distribution valve is adjusted or closed under the effect of the torsion spring calibration below, then the pressure in the B cavity is gradually reduced, so as to achieve the goal of the transformer cycle.
(two) immediate type pressure regulating valve: immediate effect torsion spring plastic film type pressure regulating valve immediate effect torsion spring plastic film type pressure regulating valve key by adjusting torsion spring, pulse damper, piston rod, high pressure gate valve, piston valve and other parts. Pulse damper is used to immediately push the piston valve and adjust the opening degree of the pressure disc to relieve the pressure and stabilize the pressure tube.
(3) Leading pressure regulator valve: Pressure regulating valve is used in the pilot operated relief valve is in the body of the opening and closing a medium to adjust the opening of the traffic, reduce the pressure of the medium, at the same time rely on the effect of valve after pressure adjustment of opening and closing opening, keep valve after pressure in a certain area, the pressure of imported continuous change of circumstances, to maintain the category of inward and outward pressure in setting After maintenance of daily life production manufacturing equipment.
Eight, float ball valve: floats need to float in the sea from beginning to end, when the river increases, floats also follow the rise. Drift up pushes the crankshaft up. The crankshaft is connected to the valve at the other end, and when raised to a certain point, the crankshaft supports the plastic piston rod pad, enclosed with water. As the water level drops, the float drops, and the crankshaft pushes the piston rod pad open.