Routine maintenance of ball valve
s: Ball valves have a long service life and maintenance-free period, which will depend on the following factors: normal working conditions, maintaining a harmonious temperature/pressure ratio, and reasonable corrosion data. When the ball valve is closed, the valve body There is still pressurized fluid inside. Before maintenance: release the line pressure and keep the valve in the open position; disconnect the power supply or air source; disconnect the actuator from the bracket. It must be confirmed that the upstream and downstream pipelines of the ball valve have been depressurized before proceeding. Disassembly, disassembly, and reassembly, care must be taken to prevent damage to the sealing surfaces of parts, especially non-metallic parts, and special tools should be used when taking out O-rings. When assembling, the bolts on the flange must be tightened symmetrically, gradually and evenly. The cleaning agent should be mixed with the ball valve. The rubber parts, plastic parts, metal parts and working medium (such as gas) are all compatible. When the working medium is gas, gasoline (GB484-89) can be used to clean metal parts. Non-metallic parts are cleaned with pure water or alcohol. Non-metallic parts should be removed from the cleaning agent immediately after cleaning, and should not be immersed for a long time. , but not for a long time, otherwise it will rust and be polluted by dust. New parts also need to be cleaned before assembly. Metal chips, fibers, grease (except for specified use), dust and other impurities, foreign objects, etc. should not be allowed during assembly. Contamination, sticking or staying on the surface of the parts or entering the inner cavity, if there is micro-leakage at the packing, the stem nut must be locked again. Note: Do not lock too tightly, usually lock for 1/4 turn to 1 turn, and the leakage will stop. A. Disassembly Put the valve in the half-open position, flush and remove the dangerous substances that may exist inside and outside the valve body. Close the ball valve, remove the connecting bolts and nuts on both flanges, and then completely remove the valve from the pipeline. Disassemble the drive device in sequence - actuator, connecting bracket, lock washer, stem nut, butterfly shrapnel, glam, wear-resistant sheet, stem packing. Remove the body cover connecting bolts and nuts, separate the valve cover from the valve body, and remove the valve cover gasket. Make sure the ball is in the closed position, which can be easily removed from the valve body and then the valve seat. Gently push the valve stem downward from the hole in the valve body until it is completely removed, and then take out the O-ring and the packing under the valve stem. Note: Please operate with caution to avoid scratching the surface of the valve stem and the sealing part of the valve body stuffing box. B. Reassembly Clean and inspect the dismantled parts. It is strongly recommended to replace the valve seat and valve cover gasket and other seals with a spare parts package. Assemble in the reverse order of disassembly. With the specified torque, cross-lock the flange connection bolts. Tighten the stem nut with the specified torque. After installing the actuator, input the corresponding signal to drive the valve core to rotate by rotating the valve stem, so that the valve can be opened and closed. If possible, please carry out pressure sealing test and performance test on the valve according to relevant standards before reinstalling the pipeline. 1. Principle: The opening and closing part of the ball valve is a sphere, and the sphere rotates around the center line of the valve body to achieve opening and closing of a valve. 2. Applicable places: Low-pressure, small-diameter pipelines are used to cut off water flow and change the distribution of water flow or places that need to be opened and closed quickly. 3. Features: 3-1. Small flow resistance; 3-2. Simple structure; 3-3. Small size and light weight; 3-4. The sealing surface material of the ball valve is made of plastic and has good sealing performance; 3-5. Operation Convenience, quick opening and closing, convenient for long-distance control; 3-6, easy maintenance, sealing rings are generally movable, easy to disassemble and replace; 3-7, when fully open or fully closed, the sealing surface of the ball and the valve seat The medium is isolated, and the passage of the medium will not cause erosion of the valve sealing surface. 4. Classification: 4-1. Commonly used ball valves are divided into floating ball valves, fixed ball valves, lifting rod ball valves, etc. according to their working principles. 4-2. The ball valve can be divided into straight-through type, three-way type and right-angle type according to its channel position. The latter two ball valves are used to distribute the medium and change the flow direction of the medium. 5. Construction and installation points: 5-1. The installation position, height, and direction of import and export must meet the design requirements, and the connection should be firm and tight. 5-2. All kinds of manual valves installed on the thermal insulation pipeline, the handle shall not be downward. 5-3. Visual inspection must be carried out before the valve is installed, and the nameplate of the valve should comply with the current national standard 'General Valve Mark' GB 12220. For valves with a working pressure greater than 1.0 MPa and the function of cutting off the main pipe, the strength and tightness performance test should be carried out before installation, and the valve can be used only after passing the test. During the strength test, the test pressure is 1.5 times the nominal pressure, and the duration is not less than 5 minutes. The valve housing and packing should be qualified without leakage. During the tightness test, the test pressure shall be 1.1 times the nominal pressure; the test pressure shall meet the requirements of GB 50243 during the duration of the test, and the sealing surface of the valve disc shall be qualified if there is no leakage. 5-4. Install a gasket between the valve flange and the pipeline flange according to the pipeline design requirements. 5-5. The ball valve with transmission mechanism shall be installed according to the provisions of the product instruction manual.
valve application is not something to be ignored or taken for granted. It is there to keep your types of industrial valves comfortable year round. To find a cost effective solution, turn to Lianke Valve Co.,Ltd..
If you cannot find the specific type of that is best for your business in the above mentioned guide, you can visit Lianke Valve for the best consultants specializing in this field, who can recommend the your are looking for. Customization is warmly welcomed here.
Lianke Valve Co.,Ltd. has developed its range of products around its own market research, which discovers customers' precise needs.
Getting valve application from an idea to production is a complex process. It involves significant research, time, planning and patience. But with the right information, the right resources and the right product, it's possible.
More than half of customers said they have faith with Lianke Valve Co.,Ltd. and valve application.