Replace Brand: John Crane mechanical seal
Specification: type 6/type 8/type 9/type 21/109b/2100/5610/8b1/8b2
Temperature: high temperature mechanical seal
Balance: Unbalanced
Type: Multi-Spring
Accreditation: ISO, SGS, UL, ROHS
Service: OEM/ODM
Origin: China
Key Features
• Classic Design: We offer high-quality aftermarket replacements for the entire range of John Crane O ring pusher mechanical seals (e.g., Type 8-1, Type 9, Type 8B1).
• High Pressure & Versatility: pusher mechanical seal Known for their ability to handle higher pressures than bellows mechanical seals due to the robust pusher design.
• Balanced Options: Available in balanced (Type 8B1) configurations for high-pressure applications.
• PTFE Backup Rings: Many pusher mechanical seal models include PTFE backup rings behind the O-ring to prevent extrusion at high pressures.
• Multi-Spring Distribution: Uses multiple small springs to provide even face loading, ensuring a compact axial length suitable for modern centrifugal pumps.
Pusher Mechanical Seal Technical Specs | Materials | ||
Mediums | Water, oil, acids, alkali, etc. | Stationary Ring | Carbon/Sic/TC |
Pressure | ≤1.2MPa | Rotary Ring | Carbon/Sic/TC/SUS304 |
Temperature | -30℃ to 200℃ | Secondary Seal | NBR/EPDM/Viton |
Speed | ≤18m/s | Spring and Metal Part | Stainless Steel |
Product Specifications
| Metric Shaft Size D1 | Size Code | D3 | D7 | L1 | L4 |
| 14 | 0140 | 25.00 | 25.00 | 25.00 | 10.00 |
| 16 | 0160 | 27.00 | 27.00 | 25.00 | 10.00 |
| 18 | 0180 | 33.00 | 33.00 | 26.00 | 11.50 |
| 20 | 0200 | 35.00 | 35.00 | 26.00 | 11.50 |
| 22 | 0220 | 37.00 | 37.00 | 26.00 | 11.50 |
| 24 | 0240 | 39.00 | 39.00 | 28.50 | 11.50 |
| 25 | 0250 | 40.00 | 40.00 | 28.50 | 11.50 |
| 28 | 0280 | 43.00 | 43.00 | 31.00 | 11.50 |
| 30 | 0300 | 45.00 | 45.00 | 31.00 | 11.50 |
| 32 | 0320 | 47.00 | 47.00 | 31.00 | 11.50 |
| 33 | 0330 | 48.00 | 48.00 | 31.00 | 11.50 |
| 35 | 0350 | 50.00 | 50.00 | 31.00 | 11.50 |
| 38 | 0380 | 55.00 | 56.00 | 31.00 | 14.00 |
| 40 | 0400 | 57.00 | 58.00 | 31.00 | 14.00 |
| 43 | 0430 | 60.00 | 61.00 | 31.00 | 14.00 |
| 45 | 0450 | 62.00 | 63.00 | 31.00 | 14.00 |
| 48 | 0480 | 65.00 | 66.00 | 31.00 | 14.00 |
| 50 | 0500 | 67.00 | 70.00 | 32.50 | 15.00 |
| 53 | 0530 | 70.00 | 73.00 | 32.50 | 15.00 |
| 55 | 0550 | 72.00 | 75.00 | 32.50 | 15.00 |
| 58 | 0580 | 79.00 | 78.00 | 37.50 | 15.00 |
| 60 | 0600 | 81.00 | 80.00 | 37.50 | 15.00 |
| 63 | 0630 | 84.00 | 83.00 | 37.50 | 15.00 |
| 65 | 0650 | 86.00 | 85.00 | 37.50 | 15.00 |
| 68 | 0680 | 89.00 | 90.00 | 34.50 | 18.00 |
| 70 | 0700 | 91.00 | 92.00 | 42.00 | 18.00 |
| 75 | 0750 | 99.00 | 97.00 | 42.00 | 18.00 |
| 80 | 0800 | 104.00 | 105.00 | 41.80 | 18.20 |
| 85 | 0850 | 109.00 | 110.00 | 41.80 | 18.20 |
| 90 | 0900 | 114.00 | 115.00 | 46.80 | 18.20 |
| 95 | 0950 | 119.00 | 120.00 | 47.80 | 17.20 |
| 100 | 1000 | 124.00 | 125.00 | 47.80 | 17.20 |
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 pusher mechanical 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
Pipeline Station: Replaced OEM Type 8B1 seals on a mainline pump. Our aftermarket version matched the pressure rating perfectly and was delivered in 1 week versus 12 weeks for the OEM.
Testimonials
We use these to service all our older API pumps. The dimensions are identical to the Crane originals, but the price allows us to be competitive on repairs.
—Pump Service Center, Texas
FAQs about O-Ring Pusher Mechanical Seals
Q: What is the difference between Type 8-1 and Type 9 mechanical seal?
A: They are mechanically similar pusher seals. The Type 9 typically uses a PTFE wedge for chemical resistance, while the Type 8-1 uses an O-ring. We supply replacements for both.
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
