Side Sealing Flat bags are made from Food Grade Virgin material. environmentally friendly and hygienic. They are water-proof, Moisture-proof, strong toughness, tear resistance, good for storage and usually for packing sugar, biscuits, candy, coffee bin, fruits , drinks or other foods. Normally width from 3 inch to 12 inch. Length from 7 inch to 22 inch. Material could be in HDPE or LDPE.
Flat Poly Bag, Flat Plastic Bag, Side Sealing Bag, Side Seal Bag, Four Side Seal Pouch, Side Sealing Plastic Bag BILLION PLASTIC MANUFACTURING CO.,LTD, JIANGMEN , https://www.jmbillion-plastics.com
Valve technical inspection and technical maintenance
The significance of the technical inspection of the valve is to ascertain the technical state of the valve in order to determine whether it can continue to use and find out and no need to adjust and repair. Technical maintenance is accomplished by pre-defined procedures that include technical inspections and adjustments, lubrication, and repairs that do not require removal of the valve from the line. Valve technology inspection should first check the state of the connecting flange or threaded joint, to ensure that there is no leakage gasket connection, to determine the state of fastened parts. Then check the connection of the valve body to the bonnet and the stuffing box. Liquid leakage can be found with the naked eye. Gas leaks are harder to find; the best way to do this is to apply soapy liquid to the condensable site (soaping bubbles at the site of the gas leak). Then check the remaining valve parts to check the status. In addition to technical inspection, technical maintenance also provides the following work. Check the valve action part of the flexibility, so the valve should be up and down full stroke. After two lifting and then check the status of the stuffing box. If necessary, tighten the nut to compress the packing or re-add the packing. Increase the filler to the valve stem has been referred to the valve stem brim and seal until the compression so far, so that the packing box can be isolated from the medium. Then put the packing gland and sleeve on the top, replace or refill the packing, and then re-compaction packing. The work should be done without stress on the pipeline. In order to check the effect of the transmission, several starts are possible. At the same time to check the closure of the channel status and signal components show the accuracy. The inspection intervals and ranges for technical maintenance depend on the working conditions of the valve, installation location, media properties and parameters and so on. After the technical examination has been completed, the results of the examination and the work done at the time of technical maintenance must be entered in a separate logbook or special card established for the valve. Gas pipeline valve is a very important component of the pipeline. Due to the high risk of gas as working medium, the valve should be observed frequently. It should also supervise and inspect its intact condition, quality and timely maintenance. Check on the packing valve should pay special attention to the status of the packing box. Asbestos oil impregnated and impregnated graphite packings are recommended for use below 200 ° C as the oil liquefies and flows at higher temperatures and as a result will reduce the pack box seal. At a temperature of 200 ~ 250 ℃ can be used when a number of single-ring to dip graphite asbestos filler. The packing ring is made of braided asbestos rope with a square cross section and a side length equal to the width of the packing box. The asbestos rope around a diameter equal to the diameter of the stem on the mandrel and cut into 45 ° angle, so that the winding lap into a circle. To fill the packing chamber fill the ring when the incision line to be staggered, and to layer by layer to sprinkle dry, pure and flaky graphite, the thickness of less than one millimeter. Special packing can be used for higher temperatures. When inspecting a gas valve, regardless of its type of piping, the following shall be accomplished: 1) external inspection of the valve; 2) disassembly of the valve to inspect and repair the sealing ring of the closing mechanism; 3) careful examination of the condition of the individual parts - , The valve disc and its fastening on the stem, the sealing ring on the valve seat and valve disc, the stem nut, the wedge or gate of the valve, bearings and other transmission parts, etc .; 4) The purpose is to detect corrosion, erosion, sealing surface abrasions and other defects; 5) After the elimination of defects and replacement of damaged parts will be replaced after the new valve; 6) The closing mechanism of the sealing Hydraulic test; 7) on the assembled valves and pipes under pressure at work under pressure test. Safety valve before the hydraulic test to be adjusted on a dedicated test bench, according to the design data to the spring to the required lifting pressure. Then, seal the valve and record the result of the adjustment in the logbook or in the technical file of the safety valve. When inspecting valves on pipes conveying corrosive gases (corrosion rates less than 0.5 mm / year), wall thickness should be regularly measured by means of special tools or instrumentation in order to monitor the corrosion loss of the valves. Valve Technical Articles