Application Case of ThreeBond TB1212 Fast Tack Oxime RTV Silicone Liquid Gasket

This case covers two mass-production sealing projects of domestic auto component factory and agricultural diesel engine manufacturer: automotive aluminum engine oil pan & agricultural machinery gearbox housing, adopting original Japan ThreeBond TB1212 solvent-free fast-cure oxime RTV formed-in-place gasket to replace traditional combined nitrile rubber and paper gasket. The new sealant solved three core pain points: high-temperature engine oil leakage, long waiting curing cycle during assembly, leakage caused by poor flange flatness. Mass production has been running stably since 2020, with annual consumption over 42,000 cartridges (310ml per piece), becoming a typical benchmark application of TB1212 in powertrain sealing industry.

ThreeBond TB1212 is single-component, solvent-free, moisture-curing oxime silicone sealant in off-white paste. At 25℃, viscosity is 100Pa·s and specific gravity is 1.04. Its core advantage is ultra-fast tack-free time of only 7min, much shorter than TB1211’s 40min to save assembly waiting time. Continuous operating temperature ranges from -60℃ to +200℃. After full curing under standard condition, Shore A hardness is 30, ultimate elongation 300%, tensile strength 2.0MPa, aluminum-to-aluminum shear strength 1.0MPa. Chemical resistance test data: +5.0% weight change after engine oil immersion, +1.3% after water soaking, -15.1% shrinkage after gasoline immersion, showing outstanding oil & water resistance. Solvent-free and low-odor formula features excellent initial pressure resistance, compatible with aluminum, cold-rolled steel, cast iron and mainstream powertrain metals, fully matching mass-production assembly requirements of engine oil pan.

1. Passenger car aluminum oil pan (0.1~0.25mm flange gap, working oil temp 95~125℃ with continuous vibration during driving): Traditional composite rubber gasket deforms permanently under thermal cycling and long-term engine oil soaking; oil leakage occurs after 6,000km driving with after-sales repair rate 6.9%. Rubber swells and cracks after gasoline immersion leading to worse leakage especially in high-temperature summer.
2. Agricultural diesel cast iron gearbox housing (uneven flange, local gap up to 0.2~0.3mm): Original paper gasket softens and breaks after long gear oil immersion; dust and rainwater penetrate into housing and cause gear rust with 7.1% field failure rate during farm operation. Conventional RTV sealants need over 30min tack-free waiting time and slow down production line efficiency seriously.
3. Various customized gaskets lead to high mold and inventory cost with poor part versatility among different engine models.

Remove grease, cutting fluid and dust on flange surface via sanding and isopropanol wiping, air dry completely before gluing. Warm up sealant to 10~25℃ at workshop before opening container to avoid inner condensation spoiling curing effect.

Automatic pneumatic dispenser applies continuous 2.5~3mm width glue bead around full flange. Benefit from 7min ultra-fast tack-free property, workers fasten all bolts and close housing within 7min after dispensing without extra waiting. High viscosity (100Pa·s) non-sag paste prevents glue sagging on vertical flange and fills uneven cast iron flange gaps effectively. Partial surface cure finishes in 24h under ambient humidity; full depth cure requires standard 23℃/50%RH environment before finished product delivery after 7 days.

Wipe uncured squeeze-out residue with clean cloth; remove cured surplus glue by original ThreeBond TB2890E cleaner. Seal leftover product tightly and store in cool dark warehouse at 10~25℃, never pour transferred leftover glue back into original container.

• Automotive oil pan: Zero leakage after 100,000km durability road test. 300% high elongation offsets thermal expansion & shrinkage of aluminum housing; after-sales leakage repair rate drops from 6.9% to below 0.25% based on certified TDS fluid resistance data.
• Agricultural gearbox: Only +1.3% weight change after hot water immersion, no water ingress or gear rust after field rain & mud exposure, field failure rate down to below 0.4%. 7min fast tack-free feature boosts production line hourly output by 28%.

Cancel customization & stock of more than 20 kinds of rubber/paper gaskets to cut mold expense; automatic dispensing replaces manual gasket placement, overall sealing cost per unit reduces by 16%.

Based on field verification, the manufacturer expands TB1212 to mass production of motorcycle crankcase housing, small construction machinery hydraulic pump flange and air compressor end cap sealing. Important Warning: TB1212 is oxime-cured silicone, will corrode copper & copper alloy under fully enclosed sealing condition, forbidden for copper component sealing; choose alcohol-type ThreeBond sealant instead.

1. Automotive Industry: Oil pan, valve cover, transmission housing, starter/generator shell, small diesel engine flange sealing for passenger car & light truck (official core recommended usage by ThreeBond Japan);
2. Agriculture & Construction Machinery: Tractor diesel housing, harvester gearbox, garden equipment power casing sealing;
3. General Mechanical & Electrical: Medium-small motor end cover, hydraulic valve flange, air compressor cabinet, stainless steel pipeline thread sealing;
4. New Energy Equipment: Waterproof & insulation sealing for small auxiliary on-board electronic control enclosure.