Super Duplex Stainless Steel Gate Valves

Product Introduction

Super duplex stainless steel gate valve is suitable for pipelines in various working conditions such as petroleum, chemical, thermal power plants, etc., to cut off or connect the pipeline medium.

By choosing different materials of valve body and valve seat, it is suitable for different media: water, oil, steam, weak acid-base solution.

The operation modes are: manual, gear transmission, electric, pneumatic, etc. The gate valve has the advantages of simple structure, convenient operation, good performance and long service life.

Duplex steel gate valve is a special stainless steel gate valve. The main feature of duplex stainless steel is that the yield strength can reach 400-550MPa, which is twice that of ordinary stainless steel, so it can save materials and reduce equipment manufacturing costs. In terms of anti-corrosion, especially under the conditions of harsh medium environment (such as seawater, high chloride ion content), the anti-pitting corrosion, crevice corrosion, stress corrosion and corrosion fatigue properties of duplex stainless steel are obviously better than ordinary austenite Stainless steel is comparable to high-alloy austenitic stainless steel, so duplex stainless steel gate valves are more suitable for extremely severe working conditions, and are used to cut off or connect strong corrosive media such as sulfuric acid in pipelines.

Duplex steel gate valves are widely used in chlor-alkali industry, soda ash industry, pharmaceutical industry, fertilizer industry, fine chemical industry, textile fiber synthesis and bleaching and dyeing industry, production of basic organic acids and inorganic salts, nitric acid industry, etc. Stainless steel gate valve has good activation-passivation transformation ability, excellent corrosion resistance, good corrosion resistance in non-oxidizing acids such as sulfuric acid, acetic acid, formic acid, phosphoric acid, and has good corrosion resistance in neutral chloride-containing media. Good pitting corrosion resistance, and good crevice corrosion resistance and stress corrosion resistance.

Features

1. The pressure-bearing parts of the valve are cast by the precision casting process, and the surface quality handwheel is cast by malleable cast iron. The shape matches the handle, and the friction force is appropriately increased to facilitate opening. And there are obvious “on” and “off” signs.

2. Castings below DN250 are precision castings, and each batch of castings is marked with a heat number for easy tracking.

3. The middle flange connecting bolts of the valve adopt stud bolts, which are convenient for maintenance and disassembly.

4. The packing gland and the gland are designed separately to ensure the concentricity of the valve stem. Reasonable stuffing box design ensures that the valve has no leakage and meets environmental protection requirements.

5. The valve cover is provided with an upper sealing ring, which conforms to the API standard of the American Petroleum Institute.

6. There is an oil cup on the valve cover, which can be regularly supplemented with solid lubricating oil to keep it easy to open and close.

Application

1. Petroleum and petrochemical equipment, such as reactors in petrochemical equipment.

2. Storage and transportation equipment for sulfuric acid, such as heat exchangers, etc.

3. The flue gas desulfurization device of the power plant is mainly used in the following parts: the tower body of the absorption tower, the flue, the shutter, the internal parts, the spray system, etc.

4. Scrubbers and fans in organic acid treatment systems.