Size

Custom

Other Attributes

Place of Origin	Zhejiang, China
Brand Name	CF680/CF670/CF676

Supply Ability

Supply Ability

10000 Piece/Pieces per Month

Product Details

1) Heat shock stablity

2) chemical corrosion-resistant

3) High temper-endure(up to 1650°)

4) Wearing/corrosion/oxidation resistant

5) Highly performance of mechanical strength

6) Cleaning or etching the hardest sub-surfaces

7) Used for grinding, lapping, and wire saw cutting as well as abrasive blasting

Material And Component Codes

Description	Material	Material Feature & Suitable Scope
Rotary /Stationary Face	Carbon	Resistant against: erosive heat. suitable for water and oil medium.
	Ceramic	Resistant against:shore hardness,abrasion. Suitable for dusted water and oil.
	Silicon Carbide	Resistant against:heat,abrasion,erosive. Suitable for industrial pumps, submersible pump sewage pump etc
	Tungsten carbide	Resistant against:heat,abrasion,erosive. Suitable for industrial pumps, submersible pump sewage pump etc
Bellow Cup gasket Oring	NBR	Resistant against:pressure,abrasion,high elasticity and mechanical strength. Suitable for water and Oil Under -20°C-120°C
	EPDM	Resistant against:heat freeze,chemical reagent depending. Suitable for water and Oil Under -40°C-150°C
	MVQ	Resistant against:heat, oil, reagent, medicine, acetone.Suitable for high temperature. Hydraulic equipment and vacum equipment Suitable for erosive medium under  -20°C-180°C
	ECO	Resistant against:ozone aging merely ocetum, ammomia ethanol. Suitable for medium -40°C-150°C
	SUS304 SUS316	Resistant against: freon, rock oil. Suitable for medium -30°C-130°C
Retainer driver ring\spring Spring seat	SUS304 SUS316	Resistant against: abrasion, antirust of feature

How to choose What you want

Let me Help you find it what mechanical seal do you want

The First step: Do you know Type name?  you can choose from the list below.

The Second Step: Do you know what material do you want? Choose from the list below.

The Third step: Do you know what shaft size?

If you don’t know any, please do not hesitate to ask us, we will help you to find out the best way.

Contact Us Now

Why Choose Us

Type 680/670/606 Metal Bellow John Crane Mechanical Seals: Advanced Sealing Solutions for Demanding Applications

1. Introduction to Metal Bellow John Crane Mechanical Seals

Metal Bellow John Crane Mechanical Seals are engineered to provide superior performance in extreme operating conditions, including high temperatures, corrosive media, and abrasive environments. The Type 680, 670, and 606 models are specifically designed for reliability in industries such as oil & gas, chemical processing, and power generation. Unlike conventional elastomer-based seals, Metal Bellow John Crane Mechanical Seals utilize welded metal bellows to eliminate secondary sealing elements, ensuring zero leakage and extended service life.

Key Advantages of Metal Bellow John Crane Mechanical Seals

✔ Zero-Leakage Design – Hermetically welded bellows prevent fugitive emissions
✔ High-Temperature Resistance – Operates from -200°C to 450°C (-328°F to 842°F)
✔ Corrosion & Abrasion Resistance – Premium materials for harsh chemical and slurry applications
✔ Reduced Maintenance – No elastomer degradation, longer lifespan

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2. Material Composition & Manufacturing Excellence

2.1 Premium Materials for Extreme Conditions

The Type 680/670/606 Metal Bellow John Crane Mechanical Seals utilize:

• Bellows Material: Hastelloy C276, Inconel 625, or 316L stainless steel for superior corrosion resistance.

• Seal Faces: Silicon carbide (SiC), tungsten carbide (WC), or diamond-coated for wear resistance.

• Secondary Seals: Flexible graphite or PTFE for high-temperature stability.

2.2 Advanced Manufacturing Process

✔ Laser Welding – Ensures hermetic sealing and structural integrity
✔ Dynamic Balancing – Minimizes vibration in high-speed applications
✔ Helium Leak Testing – Guarantees zero leakage before shipment

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3. Applications of Metal Bellow John Crane Mechanical Seals

3.1 Oil & Gas Refineries

• High-pressure hydrocarbon pumps

• Sour gas (H₂S) environments with NACE MR0175 compliance

3.2 Chemical Processing

• Acid & caustic transfer pumps (sulfuric acid, hydrochloric acid, sodium hydroxide)

• Polymerization reactor feed pumps

3.3 Power Generation

• Boiler feed pumps (up to 400°C / 752°F)

• Geothermal steam applications

3.4 Cryogenic & LNG Services

• LNG transfer pumps (-160°C / -256°F)

• Liquid nitrogen and oxygen handling

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4. Installation & Maintenance Best Practices

4.1 Proper Installation Guidelines

1. Pre-Installation Checks

• Verify shaft runout (≤0.05mm) and seal chamber dimensions.

• Ensure clean, debris-free pump internals.

2. Mounting the Seal

• Carefully slide the Metal Bellow John Crane Mechanical Seal onto the shaft.

• Secure with manufacturer-recommended torque settings.

3. Final Adjustments

• Remove shipping clips (if applicable).

• Perform a dry rotation test to confirm smooth operation.

4.2 Maintenance & Troubleshooting

Maintenance Tips:
✔ Annual inspections for bellows integrity
✔ Vibration monitoring to detect early failure signs
✔ Flush system optimization for abrasive services

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5. Why Choose Type 680/670/606 Metal Bellow John Crane Mechanical Seals?

• API 682 & ISO 21049 Compliance – Meets global industry standards.

• Customizable Designs – Available in multiple face materials and bellows configurations.

• Global Technical Support – Rapid response for troubleshooting and spare parts.

Final Recommendation:
For industries requiring high-performance, zero-leakage sealing, the Type 680/670/606 Metal Bellow John Crane Mechanical Seals deliver unmatched reliability. Their welded metal bellows design ensures long-term performance in the most demanding conditions.

Contact us today for a custom sealing solution tailored to your needs!

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Here are 12 professional Q&As about Type 680/670/606 Metal Bellow John Crane Mechanical Seals 

1. Q: What are the key differences between Type 680, 670 and 606 Metal Bellow John Crane Mechanical Seals?
   A: While all three models feature welded metal bellows, they differ in:

• Type 680: Standard duty for general chemical services

• Type 670: Heavy duty for high-pressure refinery applications

• Type 606: Specialized for extreme temperatures (-200°C to 450°C)
  All Metal Bellow John Crane Mechanical Seals share the same quality manufacturing standards.

2.Q: Why choose Metal Bellow John Crane Mechanical Seals over conventional elastomer seals?
A: Metal Bellow John Crane Mechanical Seals provide:

• 50% longer service life in harsh conditions

• Zero fugitive emissions compliance

• Elimination of elastomer degradation

• Superior thermal cycling capability
  Making them ideal for critical hydrocarbon and chemical services.

3.Q: What materials are recommended for sour gas (H2S) service?
A: For sour gas applications, Metal Bellow John Crane Mechanical Seals should use:

• NACE MR0175 compliant Hastelloy C276 bellows

• Tungsten carbide vs. carbon faces

• Flexible graphite secondary seals
  This combination resists sulfide stress cracking while maintaining seal integrity.

4.Q: How do I select the right Metal Bellow John Crane Mechanical Seal for my API 610 pump?
A: Selection requires:

1. Pump operating conditions (pressure, temperature, speed)

2. Process media characteristics

3. Shaft size and seal chamber dimensions

4. Required API flush plan
   Our engineers can recommend the optimal Type 680/670/606 configuration.

5.Q: What's the typical MTBF for these seals in refinery services?
A: Metal Bellow John Crane Mechanical Seals typically achieve:

• 3-5 years in clean hydrocarbon services

• 2-3 years in mild abrasive services

• 1-2 years in severe slurry services
  Proper flush system maintenance can extend service life by 30%.

6.Q: Can these seals handle thermal shock in FCCU applications?
A: Yes, Metal Bellow John Crane Mechanical Seals are designed for:

• Rapid temperature changes up to 300°C/hour

• Thermal cycling between -50°C to 400°C

• Continuous operation at 450°C
  Their prestressed bellows design accommodates thermal expansion/contraction.

7.Q: What maintenance is required for Metal Bellow John Crane Mechanical Seals?
A: Recommended maintenance includes:

• Monthly visual inspections

• Quarterly vibration monitoring

• Annual comprehensive checks
  Unlike conventional seals, they don't require O-ring replacements.

8.Q: How do I troubleshoot premature bellows failure?
A: For Metal Bellow John Crane Mechanical Seals showing early failure:

1. Check for excessive vibration or misalignment

2. Verify proper flush system operation

3. Inspect for chemical attack or corrosion

4. Review operating conditions vs. design limits

9.Q: Are these seals suitable for LNG cryogenic applications?
A: Absolutely. Our cryogenic Metal Bellow John Crane Mechanical Seals feature:

• Special low-temperature alloys (304L, 316L)

• Thermal contraction compensation

• LNG service certification
  Proven in -160°C LNG transfer pumps.

10.Q: What's the proper installation procedure?
A: Correct installation of Metal Bellow John Crane Mechanical Seals requires:

1. Verify shaft runout <0.05mm

2. Clean seal chamber thoroughly

3. Use alignment tools during mounting

4. Torque to manufacturer specifications

5. Remove all shipping restraints

11.Q: Can existing pumps be retrofitted with these seals?
A: Yes, our engineering team can develop retrofit kits to adapt Metal Bellow John Crane Mechanical Seals to most existing pump designs, typically improving reliability by 30-50%.

12.Q: What ROI can I expect when upgrading to these seals?
A: Documented benefits include:

• 40-60% longer MTBR vs. conventional seals

• 50% reduction in maintenance labor

• Payback period of 6-12 months
  For a customized ROI analysis, provide your current seal performance data.

Key Takeaway:
Metal Bellow John Crane Mechanical Seals provide unmatched reliability in demanding services through their robust construction and advanced materials. Their welded metal bellows design eliminates common failure points while meeting stringent environmental regulations. For application-specific recommendations, consult our sealing specialists with your operating parameters.

Pro Tip: Always reference the complete model number (680/670/606) when ordering Metal Bellow John Crane Mechanical Seals to ensure proper configuration for your specific application requirements. Our technical support team is available for emergency consultations 24/7.