The plates of the plate heat exchanger are formed by one-step punching with extremely precise molds. The plate has the same accuracy only once formed, so there is even metal point contact between the plate and the plate to ensure that the plate heat exchanger can operate normally under higher pressure and can withstand the pressure impact of the system. What materials make up the plates of the plate heat exchanger?
(1) High-grade stainless steel. Stainless steel has excellent resistance to chloride pitting and crevice corrosion. The plate heat exchanger is suitable for the medium containing salt water and inorganic acid which cannot be used with type 316. The titanium plate heat exchanger uses unalloyed titanium, which can naturally generate a passive protective film. If it is destroyed, it has "self-healing". The corrosion resistance is better than stainless steel, and it is a typical material suitable for chlorine-containing media.
(2) Titanium-palladium alloy. The plate heat exchanger uses unalloyed titanium added with palladium (0.12%~0.25%), which significantly improves the corrosion resistance of titanium in acid media.
(3) 254SMO high-grade stainless steel. It is an ultra-low-carbon high-grade stainless steel that is improved to 316 type by increasing the Mo content. It has excellent resistance to chloride pitting and crevice corrosion, and is suitable for media containing salt water and inorganic acid that cannot be used with type 316.
(4) 200/Ni201. This is a pure nickel plate containing more than 99% nickel. It is mainly used for caustic solutions (NaOH, KOH) with high concentration (50% to 70%) and high temperature (up to the boiling point). It is very sensitive to crevice corrosion caused by chlorides such as brackish water.
(5) Monel 400 is a Ni (about 70%)-Cu (about 30%) nickel-based alloy. Non-aerated sulfuric acid at a concentration below 80% and a temperature not higher than 50℃~100℃. The corrosion resistance is good in HF acid, acetic acid and caustic alkali with concentration below 50% and temperature below 100℃. It is especially suitable for acidic chloride solutions and brackish water and salt water under certain working conditions. It has good high temperature resistance. Not suitable for concentrated sulfuric acid, hydrochloric acid and nitric acid.