Huahao Sealing · Carbon Graphite Components
Huahao Sealing provides carbon graphite seal rings and bearings for ammonia, urea and phosphate fertilizer plants. Resin-impregnated grades handle 220°C with resistance to ammonia, urea liquor, phosphoric acid and caustic; carbonized grades reach 600°C for high-pressure carbamate pumps and ammonia service.
High-pressure carbamate pumps handle 15-25 MPa carbamate liquor — extremely corrosive; standard metallic bearings suffer pitting failure
Ammonia synthesis operates in high-temp high-pressure hydrogen; seal materials suffer hydrogen embrittlement and permeation
Urea melt at 140-180°C tends to crystallize and seize the seal chamber
Phosphate slurry pumps convey phosphoric acid slurry with solids, causing severe abrasive wear
Resin-impregnated graphite grade (M106K) rated 220°C, chemically inert against carbamate, ammonia and urea liquor corrosion
Carbonized graphite grade (M191T) rated 600°C, hydrogen-embrittlement resistant for high-temp high-pressure ammonia synthesis sections
Carbon graphite self-lubrication eliminates external lubricant, avoiding urea crystallization deposition and seizure in lube channels
Paired with SiC mating face of high hardness to resist abrasive wear from phosphate slurry solids
| Temperature | -50°C ~ 600°C |
| Pressure | ≤ 25 MPa |
| Speed | ≤ 20 m/s |
| Media | Ammonia, urea, carbamate, phosphoric acid |
| Grade | M106K (Resin) / M191T (Carbonized) |
| pH Range | 0-14 |
M106K resin-impregnated grade rated 220°C, chemically inert against carbamate corrosion. Pair with SiC face; seal chamber needs flush port to prevent crystallization.
M191T carbonized grade rated 600°C, hydrogen-embrittlement and permeation resistant. Carbon graphite remains chemically stable in hydrogen service without embrittlement failure.
Carbon graphite self-lubrication eliminates external grease, avoiding urea deposition in lube channels. Seal chamber should use steam jacket or low-pressure steam purge.
Select M106H antimony grade with SiC face. SiC hardness HV2500 resists slurry solids erosion; graphite self-lubrication reduces friction heat, extending seal life 3-6×.
