The heat exchange plate of the fully welded plate heat exchanger is made of special stainless steel and pressed with a special mold. The surface is smooth and not easy to scale. Its unique corrugated design enables the fluid to generate turbulent flow even at low flow rates, and has high heat transfer efficiency. No non-metallic sealing material is used, so it has high temperature and pressure resistance. It can be used for extreme working conditions with a working temperature of 300C and a pressure of 3.0Mpa. The advantage is that it has a corrugated plate structure similar to the plate heat exchanger. At the same time, it adopts a more advanced all-welding process to seal, no gasket design, and a variety of metal and alloy materials to choose from, ensuring the applicable temperature of the all-welded plate heat exchanger. Almost all heat exchange process occasions from -195 to 538 and working pressure from vacuum to 8.2MPa. And it has the characteristics of compact structure, efficient heat transfer and flexible use.