SJ Gauge: Pressure gauges or diaphragm pressure gauges, due to their measurement principles, have connectors that come into contact with the pressure source (medium). For fluids with corrosive properties, we often choose pressure gauges with plastic connectors or diaphragms. The following is a list of common plastic materials used in pressure gauges and their corrosion resistance to different pressure sources (information is for reference only, and actual conditions may vary; rely on on-site experience for accurate assessment):
(Related Product: DIT-P | Corrosion-Resistant Plastic Threaded Diaphragm Seal)
| Corrosion Resistance Table for Common Pressure Gauge Plastic Materials Symbol Explanation: ✓: Highly resistant, ○: Suitable X: Not recommended ⊗: Partially suitable (e.g., at high concentrations or in the presence of moisture). | |||||||
| Category | Name | Formula | PP | PVC | PVDF | PTFE | PFA |
| Water | H2O | ✓ | ✓ | ✓ | ✓ | ✓ | |
| Hydrogen | H2 | ✓ | ✓ | ✓ | ✓ | ✓ | |
| Nitric Oxide | N2O | ✓ | ✓ | ✓ | ✓ | ✓ | |
| Hydrogen Peroxide | H2O2 | ○ | ✓ | ○ | ✓ | ✓ | |
| Acid | Hydrochloric Acid | HCl | ✓ | ✓ | ✓ | ✓ | ✓ |
| Nitric Acid | HNO3 | ○ | ✓ | ✓ | ✓ | ✓ | |
| Sulfuric Acid | H2SO4 | ○ | ✓ | ✓ | ✓ | ✓ | |
| Hydrogen Sulfide | H2S | ✓ | ✓ | ✓ | ✓ | ✓ | |
| Carbonate | H2CO3 | ✓ | ✓ | ✓ | ✓ | ✓ | |
| Phosphoric Acid | H3PO4 | ✓ | ✓ | ✓ | ✓ | ✓ | |
| Chromic Acid | H2CrO4 | ○ | ✓ | ○ | ✓ | ✓ | |
| Hydrofluoric Acid | HF | ○ | ○ | ✓ | ✓ | ✓ | |
| Chloric Acid | HClO3 | ○ | ✓ | ✓ | ✓ | ✓ | |
| Sulfur Dioxide | SO2 | ✓ | ✓ | ✓ | ✓ | ✓ | |
| Alkali | Sodium Hydroxide | NaOH | ✓ | ✓ | ✓ | ✓ | ✓ |
| Ammonia | NH3 | – | – | – | ✓ | ✓ | |
| Salt | Ammonium Nitrate | NH4NO3 | ✓ | – | ✓ | ✓ | ✓ |
| Ammonium Sulfate | (NH4)2SO4 | ✓ | ✓ | ✓ | ✓ | ✓ | |
| Aluminum Sulfate | Al2 (SO4)3 | ✓ | ✓ | ✓ | ✓ | ✓ | |
| Copper Sulfate | CuSO4 | ✓ | ✓ | ✓ | ✓ | ✓ | |
| Ammonium Bicarbonate | NH4HCO3 | ✓ | ✓ | ✓ | ✓ | ✓ | |
| Sodium Carbonate | Na2CO3 | ✓ | ✓ | ✓ | ✓ | ✓ | |
| Sodium Bicarbonate | NaHCO3 | ○ | ✓ | ✓ | ✓ | ✓ | |
| Ammonium Chloride | NH4Cl | ✓ | ✓ | ✓ | ✓ | ✓ | |
| Potassium Chloride | KCl | ✓ | ✓ | ✓ | ✓ | ✓ | |
| Iron(III) Chloride | FeCl3 | ✓ | ✓ | ✓ | ✓ | ✓ | |
| Sodium Hypochlorite | NaOCl | ○ | ✓ | ✓ | ✓ | ✓ | |
| Aqueous | Mineral water | ✓ | ✓ | ✓ | ✓ | ✓ | |
| Sewage | ✓ | ✓ | ✓ | ✓ | ✓ | ||
| Brines | ✓ | ✓ | ✓ | ✓ | ✓ | ||
| 30% NaCl | ✓ | ✓ | ✓ | ✓ | ✓ | ||
| Beer | ✓ | ✓ | ✓ | ✓ | ✓ | ||
| Juice | ✓ | ✓ | ✓ | ✓ | ✓ | ||
| Toxicity | Sulfur | Sulfur | – | – | – | ✓ | ✓ |
| Chlorine Gas | Cl2 | ✓ | ✓ | ✓ | ✓ | ✓ | |
| Chlorine Water | Chlorinated Water | ✓ | ✓ | ✓ | ✓ | ✓ | |
| Bromine Gas | Br2 | X | X | ⊗ | ✓ | ✓ | |
| Phosgene | COCl2 | ✓ | ✓ | ✓ | ✓ | ✓ | |
| Organic | Organic Acetic Acid | CH3COOH | ✓ | ✓ | ✓ | ✓ | ✓ |
| Ammonium Acetate | CH3COONH4 | ✓ | – | – | ✓ | ✓ | |
| Glycerol | Glycerol | ✓ | ✓ | ✓ | ✓ | ✓ | |
| Xylene | C8H10 | X | X | ○ | ✓ | ✓ | |
| Methanol | CH3OH | ○ | ✓ | ✓ | ✓ | ✓ | |
| Ethanol | C2H5OH | ○ | ✓ | ✓ | ✓ | ✓ | |
| Methane | CH4 | ✓ | ✓ | ✓ | ✓ | ✓ | |
| Dichloroethylene | C2H2Cl2 | X | X | ✓ | ✓ | ✓ | |
| Chloroform | CHCl3 | X | X | ✓ | ✓ | ✓ | |
| Vinyl Chloride | C2H3Cl | X | X | ✓ | ✓ | ✓ | |
| Cellulose Acetate | cellulose acetate | – | – | – | ✓ | ✓ | |
| Citric Acid | C6H8O7 | ○ | ⊗ | ✓ | ✓ | ✓ | |
| Crude Oil | Crude | ✓ | ✓ | ✓ | ✓ | ✓ | |
| Freon | Freon | ✓ | ✓ | ✓ | ✓ | ✓ | |
(Further Reading: Corrosion Resistance Chart for Pressure Gauge with “PP Material Connector”)




