When it is necessary to clean, the drain ball valve can be opened for discharging or the filter can be taken out, after removing the impurities from the filter, reloading can be, the use and maintenance are very convenient. Large diameter strainer for hot water, cold water, steam. The general network is 18~30 mesh, ventilation network is 10~100 mesh, oil network is 100~480 mesh. It belongs to the series of crude filters of pipelines, and can also be used for filtering large particles of gas or other media. It can remove large solid impurities in the fluid when installing on pipelines, enabling the normal operation and operation of machine equipment (including the compressor, pump, etc.) and instruments to achieve stable process and guarantee safe production. It can also the with three configurations. One is the intelligent sewage discharge device, which connects the sewage ball valve with the intelligent pressure difference table. When the pressure difference reaches the set maximum, the sewage ball valve will be automatically opened to discharge; Second, it is a magnetic device, its unique magnetic properties can adsorb small iron containing elements in water, such as iron, rust or welding slag; The third is the visualization device, which can clearly see the impurities in the filter screen to remind the unit of use to clean up regularly.