Why Need Gasket Sealant?
A gasket sealant is applied to joints or gaskets to create a perfect, leak-proof seal. It fills tiny surface flaws, stops fluid or gas leaks, and makes connections last longer. Ideal for cars, machinery, and plumbing.
Why Do Solid Gaskets Leak?
- Even best-machined
flanges have tiny irregularities that solid gaskets can’t fully seal—worse on cast or sheet metal parts. - Gaskets lose compression over time (compression set).
- Pressure and vibrations push them out.
- Hard to find exact replacement sizes during repairs.
flanges have tiny irregularities that solid gaskets can’t fully seal—worse on cast or sheet metal parts.Solution: Switch to Liquid Gasket Sealants Supex liquid sealants replace solid gaskets as “Formed-in-Place” (FIPG) gaskets.
Key Benefits:
- 100% leak-proof for the assembly’s life.
- No need for expensive flange machining—works on cast/stamped parts.
- Easy to apply: manual, pneumatic, or automated.
- Zero downtime—create any shape on-site.
Choose Supex for reliable, durable seals!
Types of Liquid flange Sealants
Silicone-Based Sealants (RTV – Room Temperature Vulcanizing):
- Highly flexible, heat-resistant, and waterproof.
- Used for automotive engines, valve covers, and water pumps.
- Example: Supex 280 Silicone RTV
Anaerobic Sealants:
- Designed for metal-to-metal joints with minimal gaps.
- Cures in the absence of air, forming a strong, durable seal.
- Example: Supex 574
Non-Hardening Sealants:
- Remain soft and pliable to handle vibration and thermal expansion.
- Ideal for gaskets that may need frequent removal or adjustment.
Hardening Sealants:
- Cure to a rigid state for permanent seals.
- Often used in applications where the joint will not need to be reopened.
Copper-Based Sealants:
- Contain metallic particles for improved heat resistance and conductivity.
- Commonly used in high-temperature applications, such as exhaust systems.
Liquid Gasket Sealants:
- Applied directly to replace traditional gaskets.
- Fill surface imperfections for a custom seal.
Industries and Applications
Liquid gasketing is becoming very popular with Automotive industry. All the automotive manufacturers , viz: Passenger cars, 2 wheelers, Commercial vehicles, Tractors, Agricultural machines, Railway Engines, Gensets use Liquid gaskets for all critical flange joints.
- Oil pan sump gasket sealing
- Head gasket dressing with high temperature sealant
- camshaft cover sealing
- transmission cover sealing
- exhaust manifold gasket sealer
- differnetial gasket sealer
- thermostat gasket sealer
- water pump gasket sealer
- fuel pump gasket sealer
- valve cover gasket maker
Process plants like Power, Steel, Paper, Waste water treatment, Mining industry, textiles use ‘Liquid gasketing’ for flange sealing of various equipment like Gear Box , Oil pan, Cam shaft cover, transmission buckle up etc.
How to use RTV gasket sealant
Cleaning:
- Clean the area to be sealed such that it is free from dust, loose particles
- ensure that cleaning is done using acetone or MEK. Do not use kerosene, diesel or petrol to clean the flanges. It leaves residue that react with the sealants and create leak path.
- Use firm and dry cotton cloth and not jute or loose fabric which will remain on the flange surface.
Application:
- cut the tip of the silicone cartridge or puncture the silicone sealant tube.
- Apply a uniform bead of the sealant from the tube
- assemble the flanges within the skin formation time of rtv sealant , ie: within 10- 15 minutes for regular grade of rtv gasket sealants.
- Preferably use anaerobic theadlocker to lock the bolts after assembling.
For industrial shop floor high speed production lines we can set up fully automatic or semi automatic dispensing systems.
Supex 280, High Temperature RTV Gasket sealant
RTV Silicone sealant seals Cast iron , sheet metal flanges. 
- Can fill gap between flanges upto 2 mm
- Automotive fluids, oil, water resistant
- can withstand internal pressure upto 10 bars
- withstand temperature upto 300 C
- Flexible , can withstand loads, jerks, vibrations
- Easy to apply manually or dispensed automatically for line production
What Are Gasket Sealants?
Gasket sealants are semi-paste or liquid materials applied directly to flanges for a permanent, leak-proof seal. They fill gaps and surface imperfections completely, bonding the two surfaces into one strong unit—no separate gasket needed. Ideal for engines, gearboxes, pumps, and machinery.
Can I Use Silicone Instead of a Solid Gasket? Yes! RTV silicone sealants are excellent replacements, especially for cast, stamped, or sheet metal flanges with gaps over 1mm. They withstand temperatures up to 250°C and pressures up to 10 bars.
How Long Do Liquid Gaskets Take to Dry? RTV silicone needs 2 hours to set and 24 hours for full cure before adding fluids. Anaerobic sealants cure in about 1 hour.
Do I Need Sealant on a Rubber Gasket? Yes—coating both sides ensures a longer-lasting, leak-free seal. For rubber used as spacers, apply sealant to flange faces for maximum protection until maintenance.
Choose high-quality gasket sealants for reliable, durable performance!
3 Responses
Thanks for providing this blog related to liquid-gasket-sealant. You have explained each & everything like how to use and involved in which applications.
thank you for the blog