

Application
Properties
Application
- Sealmax Style 940M – Mill Type PTFE Envelope Gasket is manufactured by wrapping a PTFE sheet around a soft compressible filler, forming a continuous folded (milled) PTFE envelope without slits.
- This construction ensures complete PTFE coverage on all sealing surfaces, providing superior chemical resistance while the insert offers resilience and sealing strength
- Style 940M envelopes are preferred where higher integrity, better creep resistance and longer service life are required compared to slit type designs.
- Style 940M is suitable for Chemical Processing Equipment, Pharmaceutical and biotech plants, Food & beverage processing units, petrochemical and refinery services, Glass-lined reactors and fragile flange joints, corrosive fluid pipelines and vessels etc.
Properties
- Excellent chemical resistance.
- Continuous PTFE envelope (no slit exposure).
- Better creep resistance than slit type.
- Excellent sealing at low to moderate bolt loads
- Non – toxic and non-contaminating
- Suitable for glass-lined and brittle flanges
- Smooth, low-friction sealing surface
Technical Specifications | ||||
Sr.No. | Properties | Unit | Test Method Reference | Specified Values |
1. | Density | gm/cm3 | ASTM D-792 | 2.15 – 2.20 |
2. | Tensile Strength (Min.) | Mpa | ASTMD-638 | 20 – 30 |
3. | Hardness | – | Shore D | 60 |
4. | pH range | – | – | 0- 14 |
5. | Maintenance factor (m) | – | – | 2.5 |
6. | Seating stress (y) | – | – | 1500 psi |
General Specifications | |||
Sr.No. | Parameters | Specifications | Remarks |
1. | Material | 100% Virgin PTFE | – |
2. | Colour | White | – |
3. | Operating Temperature | Max 260⁰ C | – |
4. | Pressure range | Upto 60 bar | Depends on insert and service conditions |
5. | Size range | DN 15 to DN 600 and above | Customized sizes on request(Fused Type is available for bigger sizes) |
6. | Available thickness | 0.5mm to 6.0mm | Customized on requests |
7. | Available inserts | CNAF, Rubber, Graphite | Customized insert on request |