Common materials for dish heads are mainly selected based on application scenarios (e.g., pressure, temperature, corrosion environment) and industry standards. The core categories include the following:
1. Carbon Steel (Most Widely Used for General Scenarios)
Key types: Q235B, 20# steel, Q345R.
Features: Low cost, good mechanical properties (strength, ductility), and easy processing/welding.
Applications: Suitable for non-corrosive or low-corrosive environments, such as general pressure vessels (water tanks, air tanks), boilers, and oil pipelines in the petroleum and chemical industries.
2. Stainless Steel (For Corrosion-Resistant & Sanitary Requirements)
Key types: 304 (18Cr-8Ni), 316L (18Cr-12Ni-2Mo), 321 (Ti-stabilized 304).
Features: Excellent corrosion resistance (resists acid, alkali, and salt), good high-temperature stability, and easy polishing (meets sanitary standards).
Applications: Sanitary fields (food, pharmaceuticals, dairy), chemical equipment (handling corrosive media like acids), and marine engineering.
3. Alloy Steel (For High-Temperature & High-Pressure Environments
Key types: 15CrMoR (chromium-molybdenum steel), 12Cr1MoVR, SA387Gr11/22 (American standard).
Features: High creep resistance (resists deformation under long-term high temperature/pressure) and strong high-temperature strength.
Applications: High-temperature and high-pressure vessels, such as thermal power plant boilers, petrochemical cracking reactors, and hydrogenation equipment.
4. Non-Metallic Materials (For Special Corrosion or Low-Pressure Scenarios)
Key types: Glass-lined steel (carbon steel base + glass coating), FRP (Fiber-Reinforced Plastic), PTFE (Polytetrafluoroethylene)-lined steel.
Features: Extreme corrosion resistance (resists strong acids/alkalis that metals cannot withstand), lightweight (for FRP), but low pressure/temperature resistance.
Applications: Special chemical containers (handling concentrated sulfuric acid, hydrofluoric acid) and low-pressure storage tanks in the pharmaceutical industry.
