Loctite SI 5699 Grey RTV Silicone Gasket Maker 300ml

Loctite SI 5699 is a grey, one-component oxime silicone that cures with moisture from the air (RTV). The paste is thixotropic, so it stays where it is dispensed.

Henkel designed it mainly for sealing rigid flanges, such as transmissions and cast metal housings, where excellent oil resistance is needed. The oxime cure is non-corrosive. It is a sealant, not a structural adhesive: its lap shear strength is low.

Where this product is used

• Rigid flange sealing on transmissions
• Sealing cast metal housings
• Flanges that need excellent oil resistance
• Assemblies where a non-corrosive cure is needed

Features

• One component, no mixing
• Grey, thixotropic paste
• Room temperature vulcanising (RTV) moisture cure, oxime silicone
• Tack-free in 30 minutes or less at 25 °C and 50 % RH
• Non-corrosive cure
• Excellent oil resistance on rigid flanges
• Cured Shore A hardness 45 to 75, elongation at least 100 %

Key specifications

Available sizes

Selecting the right option

Other one-component silicone gasket makers in the Loctite range include Loctite SI 587 Blue High Performance RTV Silicone Gasket Maker 95g and Loctite SI 5900 Flange Sealant 300ml. Check each data sheet for the flange type and fluids it is intended for.

Using it

Mate the parts within a few minutes of dispensing, because the moisture cure starts as soon as the paste is in the air.

Allow the sealant to cure (for example seven days) before heavy service loads. Excess can be wiped off with non-polar solvents.

Storage and handling

Store unopened in a dry location, ideally between 8 °C and 21 °C. Storage below 8 °C or above 28 °C can adversely affect the properties of the product.

Limits and safety

Not recommended for pure oxygen or oxygen-rich systems, as a sealant for chlorine or other strong oxidising materials, or for contact with petrol. Lap shear strength is low (0.1 to 2.1 N/mm² depending on the substrate), so do not use it as a structural bond.

Frequently asked questions

How long does Loctite SI 5699 take to skin over?

Tack-free time is 30 minutes or less at 25 °C and 50 % RH. Allow about seven days before heavy service loads.

What is Loctite SI 5699 used for?

Rigid flange sealing with excellent oil resistance, for example on transmissions and cast metal housings. It is a one-part oxime RTV silicone and is non-corrosive.

Can I use Loctite SI 5699 with petrol?

No. Henkel does not recommend it for contact with gasoline (petrol).

What are the cured properties of Loctite SI 5699?

After 1 week at 25 °C and 50 % RH: Shore A hardness 45 to 75, elongation of at least 100 % and tensile strength of at least 2.4 N/mm².

What temperature range does Loctite SI 5699 handle?

The Henkel data sheet states no service temperature range. It gives hot strength and heat ageing charts only, so check these before using it on hot flanges.

Is Loctite SI 5699 food safe?

No. It is registered to NSF Category P1 for use as a sealant where there is no possibility of food contact in and around food processing areas. Henkel notes this is a regional approval.

Related products

See also: Loctite SI 587 Blue High Performance RTV Silicone Gasket Maker 95g, Loctite SI 5900 Flange Sealant 300ml, Loctite 598 Black RTV Silicone Gasket Maker 95g, Loctite 587 Blue Maxx Silicone Flange Sealant 300ml, Loctite 5920 Copper Maxx Silicone 85g.