Plate heat exchangers are ideal equipment for liquid-liquid and liquid-vapor heat exchange. Plate heat exchangers have been widely used in production in various industries. Commonly used are generally divided into water-water plate heat exchanger and soda-water plate heat exchanger. Plate heat exchangers also need regular maintenance. If it is not maintained in time, it may be blocked due to fouling, which will affect the safety and normal use of the equipment. Three precautions for the water-water plate heat exchanger in the maintenance process.
(1) The plate heat exchanger has a large number of plates, and needs to be cleaned one by one and replaced with new pads. Therefore, it is generally used to lift off the installation position as a whole during overhaul, and disassemble it in a suitable place for overhaul. Before disassembling the plate heat exchanger, close the medium inlet valve (and the high-pressure side valve should be closed first), and then close the outlet valve to allow the heat exchanger to slowly cool down to 40°C before discharging, then remove the connected pipes and lift off as a whole. .
(2) The maximum allowable pressure of the water-water plate heat exchanger is about 1.6MPa, and it can reach 2.0MPa under special circumstances, and the maximum allowable temperature is 160℃. The surface of the circulating water side plate has serious scale, the bottom of the scale layer is harder, and the surface layer is thicker. There are many alluvial foreign bodies on the side of the circulating water, which are mainly composed of flocs, decayed materials and water system filler fragments, which cause local blockage of the fluid channels between the sheets.
(3) The main requirements for clamping dimensions. When A<1000mm, the error does not exceed 1mm. When A>1000mm, the error is not more than 2mm, and the deviation of the stack length between bolts is not more than 0.5%A.