LPG Ball valve is evolved from the plug valve. It has the same 90 degree rotation action, except that the plug body is a sphere with a circular through hole or passage through its axis. The ratio of the sphere to the channel should be such that when the sphere is rotated 90 degrees, the sphere should be fully spherical at the inlet and outlet to cut off the flow. Ball valve only need to rotate 90 degrees of operation and a small turning moment can be closed tight. The completely equal body cavity provides a medium-sized, straight-through runner with low resistance. Ball valves are generally considered to be the most suitable for direct opening and closing, but recent developments have designed the ball valve to be throttling and controlling flow. The main features of the LPG Ball valve is its compact structure, easy operation and maintenance, suitable for general working media such as water, solvents, acids and natural gas, but also for media with bad working conditions such as oxygen, hydrogen peroxide, methane and ethylene. Ball valve body can be a whole, it can be combined. What is a ball valve: Ball valve is used with a circular channel for the opening and closing of the ball, the ball with the valve stem to open and close the valve action. The opening and closing of the ball valve is a perforated ball, rotating perpendicular to the axis of the channel, so as to achieve the purpose of opening and closing channels. LPG Ball valve is mainly used to open and close the pipeline and equipment media Ball valve works Ball valve It has the same rotation of 90 degrees of action, except that the plug body is a sphere, a circular through-hole or passage through its axis. Ball valve in the pipeline is mainly used to cut off, distribute and change the flow direction of the medium, it only needs to rotate 90 degrees of operation and a small turning moment can be closed tight. Ball valves are best suited for switching and shut-off valves, but recent developments have designed ball valves to provide throttling and control flow, such as V-ball valves. The main features of the LPG Ball valve is its compact structure, reliable sealing, simple structure, easy maintenance, sealing surface and the spherical surface is often closed, easy to be media erosion, easy to operate and repair, suitable for water, solvents, acids and natural gas and other general work Media, but also for poor working conditions of media, such as oxygen, hydrogen peroxide, methane and ethylene, etc., are widely used in various industries. Ball valve body can be a whole, it can be combined. Ball valve main features: 1. Ball valve installation direction from the restrictions, the flow of media can be arbitrary. Small fluid resistance, full diameter of the ball valve basically no flow resistance. 2. Ball valve structure is simple, relatively small size, light weight, easy maintenance. 3. Close and reliable. It has two sealing surfaces, and the ball valve sealing surface material widely used in a variety of plastic, good sealing, can achieve a complete seal. In the vacuum system has also been widely used. 4. Ball valve for regular operation, opening and closing fast, lightweight. Easy to operate, quick opening and closing, as long as 90 ° rotation from full open to full close, easy to remote control. 5. Easy maintenance, ball valve structure is simple, the seals are generally active, demolition and replacement are more convenient. 6. LPG Ball valve sealing performance. In the fully open or fully closed, the ball and valve seat sealing surface and media isolation, the media will not cause erosion of the valve sealing surface. 7. Wide range of applications, the path from small to a few millimeters, up to a few meters, from high vacuum to high pressure can be applied. 8. Because the ball valve in the process of opening and closing wipe, it can be used for medium with suspended solid particles. 9, ball valve fluid resistance. 10, ball valve without vibration, noise. Ball valve classification: According to the structure of the ball valve can be divided into: floating ball valve, fixed ball valve, flexible ball valve and oil seal ball valve; by channel can be divided into straight ball valve, angle ball valve and ball valve, etc., T-shaped and L-shaped two. By connecting party workers can be divided into threaded ball valve connection, flanged ball valve and welded ball valve three. 1, Floating Ball Valve Ball valve ball is floating, under medium pressure, the ball can produce a certain displacement and squeeze the sealing surface at the outlet end, to ensure that the outlet end of the seal. Floating ball valve structure is simple, good sealing, but the ball to withstand the load of the working medium are all passed to the outlet seal, so to consider whether the seal material can withstand the working load of the ball medium, when subjected to high pressure impact, Sphere may be offset. This structure, generally used in low pressure ball valve. 2, the fixed ball valve ball is fixed, does not produce pressure after the move. Fixed ball valve with a floating valve seat, subject to media pressure, the valve seat to move, so that the ring is pressed on the ball in order to ensure the seal. Usually with the ball on the lower shaft equipped with bearings, operating torque is small, suitable for high pressure and large diameter of the valve. In order to reduce the operating torque of the ball valve and increase the reliability of the seal, in recent years there have been oil seal ball valves, both in the sealing surface injection of special lubricants to form a layer of oil film, which enhances the tightness and reduces operating torque , More suitable for high pressure large diameter ball valve. 3, flexible ball valve (orbital ball valve) Ball valve ball is flexible. Sphere and seat ring are made of metal materials, sealing a large pressure, relying on the pressure of the media itself has reached the seal requirements, must impose external forces. This valve is suitable for high temperature and pressure medium. Elastic ball is in the lower end of the ball wall to open a flexible groove, and to obtain flexibility. When closing the channel, the wedge-shaped head of the valve stem causes the ball to expand and press against the valve seat to seal. Before turning the sphere, the wedged head is released and the sphere then restores its original shape. This results in a small gap between the sphere and the seat, which can reduce the friction and operating torque of the sealing surface. 4, V-type ball valve This ball valve is a fixed ball valve, is also a single seat ball valve, regulating performance is the best ball valve, the flow rate is equal percentage, adjustable ratio up to 100: 1. Its V-cut and metal seat between the shear effect, especially suitable for containing fibers, small solid particles, slurry and other media. 5, three-way ball valve three-way valve with T-and L-type. T-type can make the three orthogonal pipeline interconnection and cut off the third channel, from the diversion, confluence. The L-type can only connect two pipes that are orthogonal to each other, and can not maintain the interconnection of the third pipe at the same time and only serve as the distributing function. Ball valve installation and maintenance Notes: 1, the ball valve to leave the valve handle rotation position 2, the ball valve can not be used for throttling. 3, the valve ball valve with transmission mechanism should be upright installation. Features 1, three-way ball valve structure in the use of integrated structure, four seat sealing type, flange less, high reliability, the design of lightweight 2, three-way ball points T and L-type, Long service life, large circulation capacity and small resistance. 3, The LPG Ball valve is divided into two types: single type and double type. The single type is characterized in that the valve will be in the state of the control system once the power source breaks down. Temperature and Pressure Limits The nameplate shows the maximum allowable ball valve operating pressure at maximum and minimum operating temperatures. With PTFE or RTFE seat and seals, the operating temperature should be between -290C and 2000C. Other types of valve seat and seal operating temperature, should be KI factory inspection. The nominal pressure rating (PN) of the ball valve indicates the maximum working pressure of the valve at normal temperature. (For example: PN4.0, indicating that the operating pressure of -290C ~ 380C when the maximum working pressure of 40 Bar (4.0MPa)). For the precautions of the electric or pneumatic actuator, please refer to the corresponding manual. Installation 1) Remove the protective cover on both sides of the flange and flush it with the valve fully open. 2) Pre-installation should be carried out according to the provisions of the signal (electrical or gas) 整机 test (to prevent the use of vibration due to transport performance), qualified before going on-line installation (wiring according to the electric actuator circuit). 3) Flush and remove residual contaminants from clean lines (these may cause damage to the seat and ball) before preparing for connection to the pipe. 4) During the installation, please do not use the actuator part of the valve as lifting lifting point to avoid damaging the actuator and accessories. 5) This type of valve should be installed in the pipe horizontal or vertical direction. 6) The pipe near the installation point can not be lowered or subjected to external force. Pipe supports or supports can be used to eliminate the deviation of the pipelines. 7) After connecting with the pipe, cross-fasten the flange connecting bolt with the specified torque. Operation and use 1) Make sure that the piping and valves have been flushed before operation. 2) Operation of Ball Valve The valve stem is rotated by the size of the input signal of the actuator: when the valve is rotated 1/4 turn (900) in the forward direction, the valve is shut off. The valve opens when rotated 1/4 turn (900) in the reverse direction. 3) The valve is open when the direction arrow of the implementing agency is parallel to the pipeline; the valve is closed when the indicating arrow is perpendicular to the pipeline. Ball valve repair has a long service life and maintenance-free period, will depend on the following factors: normal working conditions, to maintain a harmonious temperature / pressure ratio, and reasonable corrosion data Note: the ball valve is closed, the valve body inside Pressure fluid still exists
● Before maintenance, relieve pressure on the pipeline and keep the valve in the open position
● Disconnect the power or air source before maintenance
● Detach the actuator and the support before maintenance
● Must ascertain the upper and lower pipes of the valve Disassembly and disassembly is required before disassembly and disassembly.
● Disassembly and reassembly must be performed with care to prevent damage to the sealing surfaces of parts, especially non-metallic parts. Special tools should be used when removing o-rings.
● Bolts on flanges must be symmetrical , Tighten evenly
● Non-metallic parts should be removed from the cleaning agent immediately after cleaning, not for a long time
● After cleaning, to be washed wall washer volatile (Can be used silk cloth wipers without cleaning agent) assembly, but should not be shelved for a long time, otherwise it will rust, dust pollution
● new parts also need to be cleaned before assembly
disassemble the valve in the half-open position, rinse, clear the body of dangerous substances may exist inside and outside. Close the ball valve, remove the connecting bolts and nuts on both flanges and remove the LPG Ball valve completely from the pipe. Disassemble the drive unit in sequence - actuator, connecting bracket, lock washer, stem nut, butterfly shrapnel, gland, wear plate, stem packing. Remove the cover connection bolts and nuts, separate the cover from the valve body, and remove the cover gasket. Make sure the ball is in the "off" position, which makes it easier to take it out of the valve body and then remove the valve seat. Push the valve stem down through the hole in the valve body until it is completely removed, then remove the O-ring and stem underfill. CAUTION: Exercise caution to avoid scratching the stem surface and the stuffing box sealing area of the valve body. B), reassembly cleaning and inspection remove the parts, it is strongly recommended to replace the spare parts package seat and gaskets and other gaskets seals. Assemble in the reverse order of disassembly. With the specified torque, cross-lock the flange connection bolts. With the specified torque, lock the stem nut. After installing the actuator, input the corresponding signal to rotate the valve core by rotating the valve stem to open and close the valve. If possible, please pressure-seal the valve and test the performance according to relevant standards before reassembling the pipe.
