Plate heat exchanger

The present invention relates to a flat-plate heat exchanger which includes a plurality of groove-shaped heat exchanger boards stacking to each other and edges squeezing to each other. The board can comprises a flowing pipe which lies between the heat exchanger boards and is used for cooling fluid and the other fluid. The flowing pipe does assembling to the plug-in connector with turbulence promoter board form. The heat exchanger is provided with at least four inlets and outlets at the corner of the heat exchanger board, the inlets and outlets form two vertical pipes for cooling the fluid andtwo vertical pipes for the other fluid in the laminated layer. The plug-in connector of the flowing pipe for cooling the fluid comprises one or a plurality of components. The circulating pipe for cooling fluid is provided with a plate-shaped plug-in connector which has a certain width and is used for guiding the pipe at the area near the opening. The plug-in connector is formed to be a turbulencegenerator at the middle ar