Zinc Sulfate food grade is different from technical grade, it is produced by Zinc oxide and sulfuric acid, both food grade. It can be used in nutritional supplement medicines or fortifiers. Zinc Sulfate Monohydrate, Zinc Sulfate Heptahydrate, Zinc Sulfate Food Additive, Zinc Sulfate Feed Grade Jiangsu Kolod Food Ingredients Co., Ltd. , https://www.kolodchem.com
Do not switch the valve speed when the reason for the speed and the valve off the handle
Why do not open the valve speed switch? In the pipeline quickly open and close the valve, it will have a water hammer phenomenon, in the pipe close to the valve produced a water hammer pressure value. It is calculated that for every 1 m / s change in liquid flow rate in the pipe, the pressure generated by the liquid can reach 1 MPa, not only this value is also in the form of a water surge wave from the pipe segment close to the valve approaching the speed of sound to the upstream Propagation (sound velocity of 1500 m / s in water and 1100 m / s in gasoline), which is superimposed on the original pressure at each point along the pipeline, may rupture the pipeline. Slow, gradually opening and closing the valve, due to the instantaneous time, small changes in speed, the pressure generated by the initial pressure is small, and because of the extension of time, the water shock waves spread to the upstream, will produce a reflected wave, thus offset The initial pressure of water hammer, so to avoid the pipeline overpressure accident. Valve lax treatment? 1) Cause: There are debris in the media, solid particles pad between the valve disc and valve seat. Valve stem and the valve is not good, so that the valve disc and valve seat can not be closely linked to the deviation. 2) Treatment: to ensure the media clean, if the valve is closed when the valve is found plugged phenomenon, not hard and hard off, you can quickly switch several times, so that pad stuff rushed out. Often to the stem and stem nut plus lubricant, to ensure that the valve switch flexible. The valve can not be opened, the reason is not closed and what is the treatment? I) reasons: there are debris or mismatch between the stem and the stem nut, the stem and the valve from the stem and stem nut corrosion , Valve force is too large and too tight packing pressure. 2) Treatment: often to stem and stem nut lubrication and removal of debris; stem and valve from the disassembly should be carried out overhaul; valve force is too large, when the pressure after the open valve.