Alumina/ceramic cartridge mechanical seals are hygienic, OEM-style cartridge seals developed for food, beverage, dairy, pharmaceutical and clean-process pump applications. The seal combines food-grade alumina ceramic faces with FDA-compliant elastomers such as EPDM or silicone, making it suitable for potable water, juices, syrups, dairy products, CIP/SIP cleaning cycles and mildly acidic or oxidizing food media.
The cartridge construction allows quick, error-free installation—spring load, face alignment and gland dimensions are preset at the factory. Wetted metal parts are available in stainless steel or Hastelloy C and can be electropolished to reduce product adhesion and bacterial growth. Smooth exterior geometry plus flushable gland ports support effective cleaning, sterilization and hygiene compliance in sanitary pumping systems.
Key Features
• FDA Compliant Materials: Constructed with food-grade Ceramic faces and FDA-approved EPDM or Silicone elastomers, ensuring product safety.
• Corrosion Resistant: Alumina Ceramic provides superior resistance to oxidizing agents and acidic food products compared to standard metals.
• Hygienic Design: Smooth exterior geometry and flushable gland ports allow for effective cleaning and sterilization.
• Thermal Shock Resistance: Our specific ceramic grade is engineered to withstand the rapid temperature changes of hot water washdowns better than standard commercial ceramics.
• Polished Metal Surfaces: All wetted metal parts are electropolished to prevent product adhesion and bacterial growth.
Technical Specs | Materials | ||
Mediums | Chemical, Food, Oil, Petroleum, Pharmaceuticals Paper and pulp, Sewage treatment | Stationary Ring | Carbon/Sic/Ssic/TC |
Temperature | Elastomer Dependent | Rotary Ring | Sic/Ssic/TC |
Pressure | ≤2.8MPa | Secondary Seal | Viton/EPDM/Chemraz/Kalrez/Aflas, etc. |
Speed | ≤35m/s | Spring and Metal Part | Stainless Steel/Hast C |


Product Specifications
| D1 (mm) | D2 | D3 | D5 | L1 | L2 | L3 | L5 |
| 43.5 | 104 | 12.5 | 19 | 38 | 25 | 62 | |
| 25 | 43.5 | 104 | 12.5 | 19 | 38 | 25 | 62 |
| 28 | 46.5 | 104 | 12.5 | 19 | 38 | 25 | 62 |
| 30 | 48.5 | 104 | 12.5 | 19 | 38 | 25 | 67 |
| 32 | 50.5 | 104 | 12.5 | 19 | 38 | 25 | 67 |
| 33 | 50.5 | 104 | 12.5 | 19 | 38 | 25 | 67 |
| 35 | 53.5 | 110 | 12.5 | 19 | 38 | 25 | 70 |
| 38 | 56.5 | 125 | 14.7 | 19 | 38 | 25 | 75 |
| 40 | 58.5 | 125 | 14.7 | 19 | 38 | 25 | 75 |
| 42 | 60.5 | 133 | 14.7 | 19 | 38 | 25 | 80 |
| 43 | 61.5 | 133 | 14.7 | 19 | 38 | 25 | 80 |
| 45 | 63.5 | 140 | 14.7 | 19 | 38 | 25 | 82 |
| 48 | 66.5 | 140 | 14.7 | 19 | 38 | 25 | 82 |
| 50 | 68.5 | 140 | 14.7 | 19 | 38 | 25 | 87 |
| 53 | 71.5 | 150 | 17.5 | 19 | 38 | 25 | 92 |
| 55 | 73.5 | 150 | 17.5 | 19 | 38 | 25 | 92 |
| 60 | 78.5 | 160 | 17.5 | 19 | 38 | 25 | 100 |
| 65 | 83.5 | 165 | 17.5 | 19 | 38 | 25 | 105 |
| 70 | 88.5 | 180 | 17.5 | 19 | 38 | 25 | 120 |
| 75 | 100 | 190 | 17.5 | 20.5 | 41.5 | 30 | 125 |
| 80 | 105 | 190 | 17.5 | 20.5 | 41.5 | 30 | 130 |
| 85 | 110 | 220 | 21.5 | 20.5 | 41.5 | 30 | 135 |
| 90 | 115 | 220 | 21.5 | 20.5 | 41.5 | 30 | 140 |
| 95 | 120 | 220 | 21.5 | 20.5 | 41.5 | 30 | 145 |
| 100 | 125 | 220 | 21.5 | 20.5 | 41.5 | 30 | 150 |
| D1 (inch) | D2 | D3 | D5 | L1 | L2 | L3 | L5 |
| 1.000 | 1.713 | 4.094 | 0.492 | 0.748 | 1.496 | 0.984 | 2.441 |
| 1.125 | 1.831 | 4.094 | 0.492 | 0.748 | 1.496 | 0.984 | 2.441 |
| 1.250 | 1.988 | 4.094 | 0.492 | 0.748 | 1.496 | 0.984 | 2.638 |
| 1.375 | 2.107 | 4.331 | 0.492 | 0.748 | 1.496 | 0.984 | 2.756 |
| 1.500 | 2.225 | 4.921 | 0.579 | 0.748 | 1.496 | 0.984 | 2.953 |
| 1.625 | 2.382 | 5.236 | 0.579 | 0.748 | 1.496 | 0.984 | 3.150 |
| 1.750 | 2.500 | 5.512 | 0.579 | 0.748 | 1.496 | 0.984 | 3.228 |
| 1.875 | 2.618 | 5.512 | 0.579 | 0.748 | 1.496 | 0.984 | 3.228 |
| 2.000 | 2.697 | 5.906 | 0.579 | 0.748 | 1.496 | 0.984 | 3.425 |
| 2.125 | 2.815 | 6.102 | 0.689 | 0.748 | 1.496 | 0.984 | 3.622 |
| 2.250 | 3.012 | 6.299 | 0.689 | 0.748 | 1.496 | 0.984 | 3.937 |
| 2.375 | 3.091 | 6.469 | 0.689 | 0.748 | 1.496 | 0.984 | 3.937 |
| 2.500 | 3.209 | 6.693 | 0.689 | 0.748 | 1.496 | 0.984 | 4.055 |
| 2.625 | 3.406 | 7.067 | 0.689 | 0.748 | 1.496 | 0.984 | 4.724 |
| 2.750 | 3.484 | 7.480 | 0.689 | 0.748 | 1.496 | 0.984 | 4.724 |
| 2.875 | 3.858 | 7.480 | 0.689 | 0.807 | 1.634 | 1.181 | 4.843 |
| 3.000 | 3.937 | 7.480 | 0.689 | 0.807 | 1.634 | 1.181 | 4.921 |
| 3.125 | 4.134 | 8.661 | 0.689 | 0.807 | 1.634 | 1.181 | 5.118 |
| 3.250 | 4.252 | 8.661 | 0.846 | 0.807 | 1.634 | 1.181 | 5.236 |
| 3.375 | 4.331 | 8.661 | 0.846 | 0.807 | 1.634 | 1.181 | 5.315 |
| 3.500 | 4.528 | 8.661 | 0.846 | 0.807 | 1.634 | 1.181 | 5.512 |
| 3.625 | 4.606 | 8.661 | 0.846 | 0.807 | 1.634 | 1.181 | 5.591 |
| 3.750 | 4.725 | 8.661 | 0.846 | 0.807 | 1.634 | 1.181 | 5.709 |
| 3.875 | 4.921 | 8.661 | 0.846 | 0.807 | 1.634 | 1.181 | 5.906 |
| 4.000 | 4.921 | 8.661 | 0.846 | 0.807 | 1.634 | 1.181 | 5.906 |
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 seals undergo rigorous trials, including thermal cycling and pressure tests, to ensure durability, minimal leakage, and long service life in demanding industrial environments.




Industry Solutions




Case Study
Bottling Plant: Replaced expensive SiC with Ceramic for sugar syrup pumps. Reduced costs by 30% with perfect hygiene and cleaning results.
Testimonials
We use these on our juice transfer lines. They clean up easily during CIP cycles and handle the acidic fruit juice without any pitting.
—Maintenance Supervisor, Beverage Company
FAQs
Q: Is Alumina Ceramic brittle compared to other materials?
A: Alumina Ceramic is harder than steel but can crack under heavy mechanical impact. However, in a stable centrifugal pump environment, it is extremely durable. We use high-purity 99.5% Alumina to maximize strength and thermal shock resistance.
Q: Are alumina/ceramic cartridge seals safe for food and beverage applications?
A: Yes. The seal uses food-grade alumina ceramic faces with FDA-compliant EPDM or silicone secondary seals, making it suitable for dairy, juice, syrup, bottled water, pharmaceutical liquids and other hygienic processes. All wetted metal parts can be electropolished to reduce product adhesion and bacterial growth, supporting CIP/SIP cleaning and sanitary pump requirements.
Q: Is alumina ceramic too brittle for centrifugal food pumps?
A: Alumina ceramic is harder than steel and can crack under heavy mechanical impact, but in a stable centrifugal pump environment it is very durable. MIAOYU uses high-purity alumina and engineered ceramic grades that provide excellent wear resistance, corrosion resistance and thermal-shock performance during hot-water washdowns and frequent start/stop duty.

Our company is specialized in the production of sealing materials, mechanical seals , cartridge seals.
E-mail: gechacha@aliyun.com
Mobile: +86-18758835650
WhatsApp: +86-18758835650
Add: No8-2, Jinsha road Yuelin Street, Fenghua District, Ningbo, Zhejiang