Key Features

• Alfa Laval Compatible – Drop-in Replacement: 100% interchangeable Alfa Laval pump mechanical seal for LKH-5 through LKH-60, SolidC and MR series with 12mm shaft. Same envelope, same gland bolt pattern – no pump modification.

• Carbon Graphite Faces – True Carbon Graphite Mechanical Seals Performance: Resin-impregnated, FDA-compliant carbon graphite rotary ring provides self-lubrication and dry-run protection during tank emptying – the core advantage of premium carbon graphite mechanical seals.

• Soft Face Benefit: Carbon is forgiving and conforms better to minor face irregularities, ensuring a tight seal immediately upon installation.

• Hygienic Carbon Grade: We use a resin-impregnated, FDA-approved carbon grade that is non-porous and easy to clean, unlike lower-grade industrial carbons.

• Thermal Stability: Carbon withstands the thermal shock of hot water and steam sterilization better than ceramic faces.

Seal Face & Elastomer Options

Material Guidance:

• Carbon Graphite vs SiC Rotating Face: Carbon graphite is self-lubricating — it can tolerate brief dry-running during pump start-up or tank-empty events without immediate face damage. In contrast, SiC/SiC pairs require continuous liquid film and may crack under thermal shock from CIP cold water hitting hot faces. For clean water and standard food/beverage service, Carbon/Ceramic offers the best cost-performance balance.

• 99.5% Al₂O₃ Ceramic vs SiC Stationary Seat: Alumina ceramic provides excellent chemical resistance to CIP chemicals (NaOH, HNO₃) and thermal shock stability. When matched with a carbon graphite mechanical seal rotating face, this combination delivers reliable long-term performance in typical hygienic applications. Upgrade to SiC/SiC only if trace abrasive particles are present in the pumped fluid (e.g., groundwater with fine sand) or for extended continuous duty cycles.

• EPDM vs NBR vs FKM: EPDM is the default for food/water CIP service — outstanding resistance to hot water, ozone, and dilute caustic/nitric acid. It is fully compatible with a carbon graphite mechanical seal in standard sanitary pumps. NBR is suitable only for clean water or oil service at ambient temperatures. FKM (Viton®) handles higher continuous temperatures (≤180°C) but has limited resistance to live steam and hot caustic solutions. Consult us for specific fluid compatibility.

Applications – Alfa Laval Pump Mechanical Seal Replacement for Dairy, Food & Beverage, Pharmaceutical Water Loops

• Alfa Laval LKH series centrifugal pump – LKH-5, LKH-10, LKH-20, LKH-25, LKH-35, LKH-40, LKH-50, LKH-60 (12mm shaft models)

• Alfa Laval SolidC series pump – sanitary centrifugal pump for food & dairy

• Alfa Laval MR series pump – multipurpose rotary lobe pump (12mm seal interface)

• Dairy processing – milk, cream, yogurt, whey transfer

• Beverage production – juice, beer, soft drink, CIP return loops

• Pharmaceutical water systems – WFI, purified water, buffer solution circulation

• Cosmetic manufacturing – lotion, shampoo, liquid soap filling lines

Product Specifications

Workshop

This workshop is equipped with professional processing equipment and integrated with standardized material warehousing management, enabling a one-stop production process from precision machining to finished product delivery. It ensures part machining accuracy and production efficiency, meeting various high-specification manufacturing requirements.

Product Research, Development and Testing

Our Product R&D and Testing focuses on optimizing seal performance through advanced simulation and material analysis. All alfa laval pump mechanical seals undergo rigorous trials, including thermal cycling and pressure tests, to ensure durability, minimal leakage, and long service life in demanding industrial environments.

1. CAD & FEA Engineering Design Workstation (R&D Stage)

Machine/Tool: SolidWorks 3D CAD & ANSYS Finite Element Analysis (FEA) Workstation.

Role in Production: Before machining begins, this station is used to build precise 3D mathematical profiles of the 12mm seal. It simulates thermal stress and fluid dynamics of the carbon-to-ceramic interfaces at pressure loads of up to 2.5 MPa and linear speeds of up to 15m/s, ensuring perfect structural optimization before raw material is cut.

2. High-Resolution Metallurgical Microstructure Analyzer (Material Inspection)

Machine/Tool: Polarized Metallurgical Microscope System (with digital imaging).

Role in Production: To guarantee the mechanical seal meets hygienic standards for food, beverage, and dairy loops (e.g., Alfa Laval SolidC and LKH pumps), this analyzer inspects the grain density of our resin-impregnated FDA-grade carbon graphite and Alumina Oxide Ceramic. It ensures the sealing faces are completely non-porous and free of micro-cracks.

3. Monochromatic Helium Light & Optical Flat Interferometer (Flatness Validation)

Machine/Tool: Helium Monochromatic Light Source with Precision Optical Flats.

Role in Production: To prevent fluid bypass, the contact faces of the carbon and ceramic rings must achieve sub-micron level flatness. Operators place polished sealing faces beneath a monochromatic light source; the resulting interference fringes (light bands) are monitored to verify a strict flat threshold of less than 0.6 µm (1 to 2 light bands).

4. Hydrostatic & Dynamic Multi-Parameter Seal Test Rig (Performance Testing)

Machine/Tool: Hydraulic Dynamic Pressure and Leakage Test Bench.

Role in Production: This final testing station subjects completed mechanical seal cartridges to simulated operational parameters. It evaluates secondary seal integrity (such as EPDM, NBR, and Viton compounds) during fast thermal cycling and high-pressure runs up to 2.5 MPa, logging leakage data to ensure full compliance with ISO 9001 standards.

Industry Solutions

FAQs about 12mm Carbon/Graphite Mechanical Seals for Alfa Laval Water Pump

Q: Can I use this for abrasive fluids?

A: No, Carbon is relatively soft. If your water contains sand or grit, Carbon will wear quickly. For dirty water, upgrade to Silicon Carbide (SiC) faces.

Q: Is this seal a direct replacement for my Alfa Laval water pump?

A: Yes. This 12mm carbon graphite mechanical seal is designed as a drop-in cartridge replacement for Alfa Laval centrifugal pumps (such as the LKH, SolidC, or MR series) that use a 12mm shaft diameter. Its dimensions and configuration are engineered to match OEM specifications, allowing for straightforward installation without pump modification.

Q: Do you supply Alfa Laval pump mechanical seal replacements as a manufacturer with factory direct price?

A: Yes. MIAOYU is an ISO 9001 certified manufacturer of carbon graphite mechanical seals in China. We supply directly to pump distributors, OEMs and end users at factory direct prices – no middleman markup. OEM/private label packaging, bulk discounts and annual contracts are available.