Parameter
| Structure |
Internally mounted single-end face, single-spring, unbalanced, lug-driven, arbitrary rotation direction, conforming to JB/T1472 standard, sleeve transmission structure. |
| Shaft Diameter |
Common sizes range from 16 to 120 mm (e.g., 104U-25/40/50/65/80/100). |
| Pressure (MPa) |
Standard pressure ≤ 1.0 MPa (10 bar);
conventional selection ≤ 0.8 MPa is more reliable;
balanced modification can reach 1.6 MPa |
|
Temperature(According to auxiliary sealing)
|
NBR: -20～80℃
FKM (Fluoropolymer): -20～180℃
PTFE/FFKM: -40～200℃ |
|
Linear Velocity/Rotational Speed
|
≤15 m/s (suitable for ≤3000 rpm, speed reduction is required for large shaft diameters);
SiC-SiC high wear resistance can reach up to 18 m/s |
|
Common Material Combinations
|
Friction pairs: Graphite/Silicon Carbide (SiC), Graphite/Hard Alloy (WC), SiC-SiC (highly abrasive)
Auxiliary seals: NBR (oil/water), FKM (acid and alkali resistant), EPDM (water/steam resistant), PTFE (highly corrosive)
Metal parts: 304/316L stainless steel; Hastelloy optional for special applications |
Application areas/scenarios
1. Water Treatment: Municipal sewage, industrial wastewater, circulating water, clean water, seawater, aqueous media containing trace particles (<1%), low abrasiveness.
2. Petrochemical/Pharmaceutical: Transporting neutral to weakly corrosive, non-crystalline media such as oils, solvents, methanol, ethanol, acetone, dilute acids and alkalis, salt solutions, pharmaceutical solutions, and syrups.
3. General Industry: Clean water pumps, pipeline pumps, chemical centrifugal pumps, screw pumps, oil pumps, papermaking equipment, etc., suitable for conventional operating conditions without strong abrasiveness or strong vacuum.
4. Food/Papermaking: Clean process media, black liquor from pulp (low abrasiveness), requires food-grade materials (316L + PTFE).
FAQ
1. Leakage Issues (Most Common)
– Static sealing surface leakage: Check if the stationary ring seals (O-rings, V-rings) are aged, deformed, or missized. Replace with seals of the same specifications that are resistant to the medium and temperature. If the clearance between the stationary ring and the gland is too large, the stationary ring needs to be re-machined or replaced.
– Dynamic sealing surface leakage: Check the sealing end faces of the dynamic and stationary rings for scratches, wear, or chipping. Minor scratches can be repaired by grinding; for severe scratches, replace the sealing ring directly. Also, confirm if the spring compression is appropriate. If insufficient compression, add gaskets; if excessive compression, reduce the number of gaskets.
– Leakage at the bushing-shaft mating point: Check if the bushing seal is damaged or if the clearance between the bushing and the shaft is too large. Replace the seal or re-grind the bushing.
2. Abnormal Wear
– Excessive end face wear: If due to particulate impurities in the medium, a filter needs to be installed; if due to insufficient lubrication, a self-lubricating seal such as an impregnated graphite ring can be used, or an external flushing fluid (such as a clean liquid of the same medium) can be introduced.
– Shaft sleeve wear: Replace the shaft sleeve with one made of wear-resistant material, and adjust the coaxiality of the sealing cavity and the shaft to avoid uneven wear.
3. Overheating and Burnout
– Excessive sealing cavity temperature: Check for blockages in the cooling system and clean the cooling pipes; if the medium temperature itself is too high, use high-temperature resistant sealing materials (such as silicon nitride ceramic rings or fluororubber sealing rings).
– Spring failure leading to poor end-face contact: Replace fatigued or corroded springs with corrosion-resistant spring materials such as stainless steel, and ensure uniform spring compression.
4. Vibration and Abnormal Noise
– Coaxiality Deviation: Recalibrate the coaxiality of the pump shaft and motor shaft, adjust the radial runout of the sealing cavity and shaft, and control it within the allowable range.
– Loose Parts: Check whether the gland bolts and drive pins are loose, tighten the bolts evenly according to the specified torque, and replace worn drive pins.
5. Short lifespan of the seal
– Material mismatch with the medium: Replace the sealing material according to the characteristics of the medium (e.g., use Hastelloy or PTFE for corrosive media; use silicon carbide for high-temperature media).
– Improper installation: Strictly follow the installation specifications to avoid impact or scratches on the sealing surface, and ensure that no impurities enter the sealing cavity during installation.
