In hydrometallurgy, particularly in zinc electrowinning processes, the sealing performance of pumps directly impacts equipment lifespan and production efficiency. As a Chinese copper & zinc EW plant EPC service supplier, we understand the critical role of sealing technology. Recently, many clients have inquired about seal selection for pumps — K-type seals vs. G4-type seals. This article provides a detailed comparison from structural, performance, and cost perspectives.
Structural Comparison of Seals
1. K-Type Seal (Multi-Layer Composite Design)
The K-type seal consists of a polyurethane body and wear-resistant rings (e.g., PTFE), featuring a three-layer stacked design with dust-proof skirts. Key advantages include:
- Strong Eccentricity Resistance: Adapts to minor pump shaft misalignment, reducing leakage risks.
- Self-Lubricating: Eliminates the need for additional lubrication, lowering maintenance frequency.
- Wear & High-Temperature Resistance: Japanese-imported materials withstand slurry abrasion.
2. G4 Seal (O-Ring + Backup Ring)
The G4 seal combines an elastic rubber O-ring with a PTFE backup ring. While effective for high-pressure sealing (up to 50 MPa), it requires a cooling system and precise groove machining.
Key Performance and Cost Analysis
Criteria | K-Type Seal | G4 Seal |
Suitable Media | Slurry, particle-laden liquids | High-pressure oil, chemicals |
Friction | Low (PTFE wear-resistant ring) | High (O-ring dynamic friction) |
Maintenance Cost | Easy replacement, low per-use | Downtime + cooling system |
Price | Lower (economies of scale) | Higher (material + setup) |
Note:
- The three-layer design of K-type seals prevents slurry leakage, while G4 seals may leak at low pressure due to O-ring deformation.
- For highly corrosive electrolytes in zinc electrowinning, K-type seals demonstrate superior chemical resistance.
Why K-Type Seals Are Preferred for Zinc Electrowinning Pumps?
1. Cost Efficiency
K-type seals utilize modular design and mass production, resulting in lower prices than G4 seals. The absence of cooling systems further reduces upfront costs.
2. Adaptability to Harsh Conditions
- Slurry Environments: Multi-layer design blocks particle intrusion.
- Frequent Start-Stop Cycles: Low friction extends seal lifespan.
- High-Temperature Tolerance: Materials withstand >120°C without water cooling.
3. Simplified Maintenance
Replacement can be performed by a single technician, minimizing downtime. For example, in an African zinc mine project using 250 K-type sealed pumps, annual maintenance costs dropped by 35%.
Selection Guide: Focus on Total Lifecycle Cost
1. Seal performance depends not only on design but also on:
- Media Characteristics: Electrolyte concentration, particle content.
- Operational Parameters: Pressure, flow rate, start-stop frequency.
- System Design: Pipeline layout, filtration precision.
2. Choose K-Type Seals if your application involves:
- Slurry with solid particles (e.g., zinc electrowinning)
- Low maintenance costs and long service life
- Budget constraints without compromising reliability
Conclusion
With rich experience of expertise in sealing solutions, PRS delivers customized services to global clients. In zinc electrowinning, K-type seals have become the industry standard due to their cost-effectiveness, adaptability, and ease of maintenance. For testing or case studies, contact the PRS team—we provide full lifecycle support for your projects.
