Double Face Mechanical Seal 224uu - Corrosion Resistant 35~85mm Shaft Seal for

224UU Double Face Mechanical Seal is a widely used standard back-to-back double-end, unbalanced, multi-spring mechanical seal compliant with international standards including DIN24960, ISO3069, and GB6556. It is designed for reliable operation in various industrial pump and mixer applications, providing enhanced leakage protection compared to single-face seals.

Medium: Weak acid and weak base liquid.

This product is required for cool rinsing with rapid flowing. Select reasonable frication disc as per work condition, and is to run soundly for long time in ISO02858 chemical pump.

Double end face, small spring and driving sleeve to drive, non balanced type, machinery seal with ant-erosion.

1. wear resistant
2. superior sealing effects
3. low friction
4. easy replacement
5. customized mold
6. quality management system
7. exquisite packaging
8. wide application
9. drawing will be provided for free with mass production

• Water Treatment Industry: Freshwater pumps, seawater pumps, wastewater treatment pumps, circulation pumps
• Chemical Processing: Weak acids, alkalis, salt solutions, chemical transfer pumps, reactor agitators
• General Industry: Cooling water systems, boiler feed pumps, hydraulic systems, food and beverage processing equipment
• Special Applications: Pumps handling toxic, flammable, or explosive media requiring zero leakage protection (when used with appropriate buffer fluid)
• Marine & Offshore: Sea water circulation pumps, ballast pumps, bilge pumps

Port of Loading: Shanghai

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

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

• 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: For corrosive media such as weak acids, alkalis, or salt solutions, the following material combinations are optimal:

• Seal face: Silicon Carbide (SiC)/Silicon Carbide (SiC) (excellent corrosion and wear resistance)
• Metal components: SS316 or Hastelloy C (enhanced corrosion resistance compared to standard SS304)
• Secondary seal: PTFE (compatible with most corrosive chemicals, temperature range -40°C to 200°C)
• For strong corrosive environments (e.g., concentrated acids), replace metal components with Hastelloy C276 and secondary seals with perfluoroelastomer (FFKM).

A: The standard shaft diameter range of 224uu seals is 15–85 mm (0.6–3.3 in). To confirm compatibility:

1. Measure the actual shaft diameter of the pump and check if it falls within the standard range.
2. Verify the shaft surface roughness (recommended Ra 0.2–0.4 μm) and tolerance (h7 or h8) to avoid seal lip damage.
3. For non-standard shaft diameters, contact the manufacturer for custom-sized 224uu seals.

A: Yes, but two key modifications are required:

1. The pump seal chamber must have enough space to accommodate the back-to-back double-face structure of the 224uu seal.
2. A buffer fluid system needs to be added (closed-loop or external supply) to fill the cavity between the two sealing faces, which is not required for single-face seals.
3. This replacement is suitable for upgrading pumps handling toxic, flammable, or leakage-sensitive media.

A: The performance limits depend on the selected seal material combination:

• Pressure range: Standard version supports vacuum to 0.8 MPa (8 bar/g, 116 psi/g); for higher pressure (up to 1.6 MPa), contact the manufacturer for a reinforced spring version.
• Temperature range:
  • NBR secondary seal: -40°C to 120°C
  • FKM secondary seal: -20°C to 220°C
  • PTFE secondary seal: -40°C to 200°C

  Exceeding the temperature limit will cause the secondary seal to age, harden, and lose sealing performance.

A: Yes, it is one of the ideal sealing solutions for such media, but the following conditions must be met:

1. Use a closed-loop buffer fluid system to prevent toxic/flammable process fluid from leaking into the environment.
2. Select flame-retardant buffer fluid (e.g., mineral oil with fire-resistant additives) to avoid fire risks.
3. Equip the buffer fluid system with a leakage detection sensor to trigger an alarm in case of seal failure.
4. This application is widely used in chemical, petrochemical, and pharmaceutical industries.

A: Absolutely. Wastewater treatment pumps typically handle media containing suspended solids, and the 224uu seal is adapted through the following configurations:

• Seal face material: Tungsten Carbide (TC)/Silicon Carbide (SiC) (resistant to wear from suspended particles)
• Secondary seal: EPDM or NBR (excellent resistance to sewage corrosion and microbial degradation)
• Auxiliary measure: Install a flushing pipeline to introduce clean water into the seal chamber, reducing particle deposition on the sealing faces.