Description:
Replacement of John Crane 680, welded metal bellow seals design.
The Type 680 is the ideal seal for general-purpose applications. Its rotating Alloy-20 bellows provide corrosion resistance in a broad range of corrosive media. Its cost-effective design, combined with a reliable performance history, has made the Type 680 a standard for low-temperature applications found in the chemical, water and wastewater, pulp and paper, and utility industries. The seal is available with hard faces for abrasive applications and a wide range of elastomers to cover a broad range of applications.
Operating Range:
Temperature: -75° C to +290° C/-100° F to +550° F
Speed: Up to 25mps / 5, 000 FPM
Pressure: Vacuum to 25 barg/360 psig
Standard size: 18-115mm/0.75''-5.25''
Equivalent to John crane Type 680
Material:
Bellows: SS-680 Alloy 20 (UNS N08020)
End-Fittings: SS-680 Alloy 20
Insert/Primary Ring: Premium Carbon Grade; Tungsten Carbide, Silicon Carbide;
Static Seals: Fluorocarbon, EPR, PTFE- Encapsulated Fluorocarbon, Nitrile, Perfluoroelastomer
Applications: Oil,light hydrocarbon,aromatic hydrocarbon, organic solvents,weak acids, alkali,Ammonia,etc.
Metal bellow seals Size: 12mm~112mm in inch

680 Dimentions(mm) | ||
A | B | C |
18 | 32.0 | 27.5 |
20 | 33.3 | 27.5 |
22 | 36.0 | 27.5 |
24 | 38.1 | 30.0 |
25 | 39.0 | 30.0 |
28 | 42.0 | 32.5 |
30 | 44.0 | 32.5 |
32 | 46.0 | 32.5 |
33 | 47.0 | 32.5 |
35 | 49.2 | 32.5 |
38 | 52.4 | 34.0 |
40 | 55.6 | 34.0 |
43 | 58.7 | 34.0 |
45 | 58.7 | 34.0 |
48 | 61.9 | 34.0 |
50 | 65.1 | 34.5 |
53 | 68.3 | 34.5 |
55 | 71.0 | 34.5 |
60 | 74.6 | 39.5 |
65 | 84.1 | 39.5 |
70 | 87.3 | 45.0 |
75 | 95.3 | 45.0 |
80 | 98.4 | 44.5 |
85 | 104.8 | 44.5 |
90 | 108.0 | 49.5 |
95 | 114.3 | 49.5 |
100 | 120.7 | 49.5 |
105 | 131.7 | 48.3 |
110 | 138.1 | 48.3 |
115 | 144.5 | 48.3 |
680 Dimentions(mm) | ||
A | B | C |
0.750 | 1.312 | 1.250 |
0.875 | 1.437 | 1.250 |
0.937 | 1.500 | 1.250 |
1.000 | 1.562 | 1.250 |
1.125 | 1.687 | 1.250 |
1.250 | 1.812 | 1.312 |
1.375 | 1.937 | 1.437 |
1.500 | 2.062 | 1.437 |
1.625 | 2.187 | 1.437 |
1.750 | 2.312 | 1.437 |
1.875 | 2.437 | 1.500 |
2.000 | 2.562 | 1.500 |
2.125 | 2.687 | 1.500 |
2.250 | 2.812 | 1.562 |
2.375 | 2.937 | 1.562 |
2.500 | 3.187 | 1.562 |
2.625 | 3.312 | 1.625 |
2.750 | 3.437 | 1.625 |
2.875 | 3.625 | 1.687 |
3.000 | 3.750 | 1.687 |
3.125 | 3.875 | 1.750 |
3.250 | 4.000 | 1.750 |
3.375 | 4.125 | 1.750 |
3.500 | 4.250 | 1.875 |
3.625 | 4.375 | 1.875 |
3.750 | 4.500 | 1.875 |
3.875 | 4.625 | 1.875 |
4.000 | 4.750 | 1.875 |
4.250 | 5.187 | 1.903 |
4.500 | 5.438 | 1.903 |
4.750 | 5.688 | 1.903 |
5.000 | 5.938 | 1.903 |
5.250 | 6.213 | 1.903 |
Structural Features: single end, balanced, independent direction of rotation, bellow transmission. The bellow provides sealing faces with the closing force and also transmits the torque.
The O-ring does,not have axial movements so it has good tracing ability and strong capacity of resisting disturbance. This seal component is easy to install and adjust and hasespecially good performances of being used in medium-and-low viscosity mediums.
Industrial Standards: DIN24960, ISO3069, GB6556, EN12756
Scopes of Application: widely used in petrochemical engineering, oil refining, chemical processing, chemical fiber manufacturing, food and beverage processing, pharmacy,
thermoelectricity and paper making. Designed for chemical pumps, oil pumps, screw pumps, compressors and oil extraction equipment.






We offer products and services to a wide range of mechanical seal users across the nation. We supply electric motor and pump repair shops, HVAC contractors, municipalities, utility companies (electric, power and water) and a variety of other distributors.
As Follows:
We are always committed to the imported mechanical seals localization and have accumulated a wealth of experience .
Our product range includes Component Seals, Metal Bellow Seals, Cartridge Seals, Agitator seals, Dry Gas Seals and Split Seals.
To great our service, we present the products and solutions while using the very good top quality at the reasonable cost for Metal Bellow Mechanical Seals. To ensure you get what exactly you need, our professional team will help you work through all the details straight to your target. With our powerful team support, you would not have to worry about anything. Our company establishes the management system in strict accordance with the requirements of international standards and makes detailed after-sales service commitment.
We are manufacturer.We are based in Hangzhou, China, start from 2010,sell to Domestic Market(33.00%),North America(15.00%),South America(10.00%),Western Europe(8.00%),Eastern Europe(6.00%),Souther Europe(6.00%),Southeast Asia(5.00%),Mid East(5.00%),Northern Europe(5.00%),Oceania(2.00%),South Asia(2.00%),Africa(00.00%),Eastern Asia(00.00%),Central America(00.00%). There are total about 51-100 people in our office.
2. how can we guarantee quality?
Always a pre-production sample before mass production; Always final Inspection before shipment;
3.what can you buy from us?
PTFE Seals/Oil Seals/O Rings/Rubber Seals/Plastic Seals/Mechanical Seal/O-RING/ RING Seals.
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