Plate exchange and heat exchanger materials I: 904L, sus890l stainless steel

This kind of austenitic stainless steel with high cost performance, which takes into account the price and corrosion resistance, has good corrosion resistance, and is especially suitable for the general sulfuric acid, phosphoric acid and halide (containing cl-, f-). Because of the high Cr, Ni and Mo content, it has good resistance to stress corrosion, pitting and crevice corrosion. Applicable conditions in chlorine containing medium.

Plate exchange and heat exchanger material II: 254 SMO advanced stainless steel

The 316 type ultra-low carbon advanced stainless steel, which is improved by increasing Mo content, has excellent resistance to corrosion of chloride spots and crevice, and is suitable for medium containing salt water and inorganic acid of type 316.

Plate exchange and heat exchanger material 3: titanium

The non alloyed titanium, light weight and density of 4.51, can naturally generate passivation protection film (Ti2O3). If it is damaged, it has "self-healing", so the corrosion resistance is better than that of stainless steel, which is suitable for the typical materials containing chlorine (Cl concentration > 200mg/l, temperature ≤ 130 ℃). In seawater and other chloride solutions (such as CaCl2) not exceeding 120 ° C, they are actually not subject to corrosion. Generally, it can be used for seawater below 135 ℃ and salt water (NaCl) of various concentrations below 165 ℃.

Titanium has good corrosion resistance in organic acids (such as concentrated nitric acid, concentrated carbonate, etc.) and dilute alkaline solution below boiling point.

Titanium has poor corrosion resistance in H2SO4, HCl, HF and wangshui. In some concentrated chloride solutions (such as pH > 7, chloride concentration > 200mg/l) at high temperature (above 120 ℃), crevice corrosion or stress corrosion may also be caused. At this time, titanium palladium alloy should be selected.

Materials for plate exchange and heat exchanger 4: titanium palladium alloy

This is the non alloyed titanium with palladium (0.12% - 0.25%) added, which obviously improves the corrosion resistance of titanium in acid medium, especially in less severe conditions. For example, the corrosion resistance of nitric acid with 70% concentration, hydrochloric acid containing oxidized ions (such as Fe +, Cu +, and electroplating solution) is good. In addition, it can be used for dilute sulfuric acid with concentration ≤ 10% and temperature ≤ 70 ℃.

Plate exchange and heat exchanger materials 5: nickel 200

This is a pure nickel plate containing more than 99 percent nickel. It is mainly used for caustic solution (NaOH, Koh, etc.) with high concentration (50% - 70%), high temperature (which can reach boiling point). However, it is sensitive to crevice corrosion caused by chlorides such as brackish water.

Material for plate exchange and heat exchanger 6: Hastelloy C-276

It has good corrosion resistance: almost free from the influence of CL; excellent corrosion resistance to sulfuric acid of various concentrations, and is one of the few materials that can be used for hot concentrated sulfuric acid; widely used in organic acids (such as formic acid, acetic acid), high temperature HF acid and hydrochloric acid (＜ 40%), phosphoric acid (＜ 50%), chloride, fluoride and organic solvents (such as methanol and ethanol).

Material for plate exchange and heat exchanger 7: Monel 400

Ni (about 70%) Cu (about 30%) nickel base alloy. In the medium of sulfuric acid with concentration below 80%, temperature not higher than 50 ℃ ~100 ℃, HF acid with concentration below 50%, temperature below 100 ℃, acetic acid and caustic soda, the corrosion resistance is good. It is especially suitable for acid chloride solution and brackish water and salt water under certain conditions; it has good high temperature resistance. However, it is not suitable for concentrated sulfuric acid, hydrochloric acid and nitric acid, and is sensitive to the erosion of mercury (sometimes as impurities).

Plate exchange and heat exchanger material 8: Incoloy825

It is suitable for sulfuric acid of various concentrations at low temperature; in caustic soda (such as NaOH) solution with concentration of 50% - 70%, it has good corrosion resistance and does not produce stress corrosion cracking. However, it is sensitive to crevice corrosion caused by chloride. In addition, the stamping performance is not very good, so it is not the commonly used material of sheet.

【GO BACK】