They are mounted on the end of the suction pipe in the pump suction lines and on the suction end of the pipe receiving water from the tank in the water tanks. It is the equipment that prevents dirt from entering the pipe. They are manufactured as flanged. The crepine sheet is made of AISI 316 stainless material. The wall thickness including DN 400 is at least 3 mm. DN 450 and DN 600 wall thickness is at least 4 mm. DN 700 and above at least 5 mm and environmental reinforcement made of stainless material for strength. Connection bolts A2 70 stainless steel. The length L of the crepine is equal to or greater than 1.5 times the diameter. The total area of the holes in the strainer is 2 times larger than the cross-sectional area of the pipe diameter.