Water Pump Single Spring Seal JG108

JG108 is a single‑spring, rubber bellows, single‑face, unbalanced mechanical seal tailored for water pumps, widely used in clean water, light corrosive fluids, and low‑pressure/medium‑temperature scenarios ( pipeline pumps, submersible pumps ). It features simple installation, cost‑effectiveness, and reliable performance, with the bellows serving as both the secondary seal and drive component.

• Single face plus framework oil seal
• Independent direction of rotation.
• Multi-springs do not contact with the medium against blocking.
• Easy for installation and maintenance.
• Excellent wear-resistant friction pairs.
• Double-balanced structure on the side of the medium.
• Short inboard length.
• Compensated by the mating ring.
• Low-pressure circulating water is introduced between the primary seal and oil seal, which improves the lubrication of the first seal and carries off the friction heat and leakage.

Operating Limited:

Material:

Advantages:

1. Rubber bellows eliminates torque transmission via bonding; the rotating ring is driven by an L‑ring + spring, enabling easy replacement.
2. Single‑spring design resists clogging, suitable for fluids with minimal particles.
3. Bidirectional rotation compatibility, adaptable to most water pump rotation directions.
4. Low cost, simple installation, and minimal maintenance.

Application:

• Water and waste water technology
• Chemical industry
• Refining technology
• Dirty, abrasive and solid containing media
• Fugitive hydrocarbons (no API seal!)
• Sticky and stringy media
• Chemical standard pumps
• Sewage pumps

Shipping & Payment Terms:

Port of Loading: Shanghai

Shipping Method: DHL,UPS,FEDEX,TNT, etc

Payment Terms: T/T, Western Union, money gram

Our services:

• OEM/ODM orders are available for our factory
• Accept customized mechanical seals according to your drawing or requirements
• Small quantity is accepted
• Provides excellent quality with competitive price

A: The JG108 seal is widely compatible with common water pump models, including:

• IS series clean water centrifugal pumps
• IR series hot water circulation pumps
• Pipeline booster pumps
• Small submersible pumps
• General industrial low-pressure water transfer pumps

  It is suitable for shaft diameters of 10–55 mm (common sizes: 12, 20, 25, 30 mm), which covers most small-to-medium water pump specifications.

A: For hot water (≤120°C) applications:

• Seal faces: Silicon Carbide (stationary) + Impregnated Graphite (rotating) (excellent heat resistance and low friction)
• Bellows/secondary seal: EPDM (resists hot water aging, temperature range -20°C to 120°C)
• Metal components: 304 stainless steel (corrosion resistance to hot water)

  This combination ensures stable performance and a service life of 8,000–10,000 hours under normal conditions.

A: The standard performance limits of JG108 are:

• Max pressure: ≤0.8 MPa (8 bar; not suitable for high-pressure pumps >0.8 MPa)
• Temperature range: Depends on the elastomer:
  • NBR (water): -20°C to 80°C
  • EPDM (hot water): -20°C to 120°C
  • FKM (weak chemicals): -20°C to 150°C (note: FKM is not recommended for pure water due to poor water resistance)

    Exceeding these limits will cause rapid aging of the rubber bellows or seal face damage.

A: Key installation precautions:

1. Cleanliness: Ensure the pump shaft, shaft sleeve, and seal chamber are free of burrs, rust, or debris (to avoid scratching the seal face or bellows).
2. Compression control: Adjust the spring/bellows compression to 3–5 mm (over-compression causes seal face overheating; under-compression leads to leakage).
3. Coaxiality: The fit tolerance between the shaft sleeve and pump shaft should be H7/h6 (to reduce eccentric wear of the seal face).
4. Lubrication: Apply a thin layer of medium-compatible lubricant (e.g., glycerin for water) to the O-rings and shaft surface before installation.

A: Common causes and solutions for excessive leakage:

1. Aged/damaged rubber bellows: Replace the entire seal (the bellows is an integrated component of JG108).
2. Scratched/worn seal faces: Lap the seal faces (if scratches are minor) or replace the seal face assembly.
3. Insufficient spring compression: Re-adjust the seal installation position to ensure 3–5 mm compression.
4. Impurities entering the seal chamber: Clean the seal chamber and add a flushing line (for particle-containing media).