Cures Quickly to Seal Hydraulic and Pneumatic Pipes and Fittings
Our 3M™ Scotch-Weld™ Low Viscosity Air/Hydraulic Sealant HP42 is a one-component, anaerobic sealant that cures and seals hydraulic and pneumatic pipes and fittings. This general purpose, low viscosity pipe sealant is fast-curing, sealing almost instantly. It is formulated to resist pressure and vibration as well as lock and seal medium to coarse straight and tapered threads.
Recommended Applications
- Pressure vessels
- Air compressors
- Hydraulic and pneumatic systems
Features of a Rapid Seal
Our 3M™ Scotch-Weld™ Low Viscosity Air/Hydraulic Sealant HP42 provides an almost instant low-pressure seal. A high-pressure seal results when the bond is fully cured. It seals quickly to stop leaks when applied to threads or compression fittings of most metal and certain plastic pipes, without shredding, evaporation or shrinkage. In addition, this sealant prevents galling as well as helps eliminate the waste and mess of leaking hydraulic fluids, oil, fuel and lubricants.
Formulated for Speed and Strength
Offering a rapid seal that withstands heat, pressure and vibration, 3M™ Scotch-Weld™ Low Viscosity Air/Hydraulic Sealant HP42 is an excellent solution for fast results. Resilient and durable, this pipe sealant is formulated to produce the strong seal necessary for a wide variety of demanding applications.
Understanding Anaerobic Adhesives
Anaerobic adhesives are uniquely formulated to cure in the absence of oxygen. The term “anaerobic” means “living without air” and when the oxygen is excluded, a chemical chain reaction begins that causes the adhesive to polymerize. Contact with metal speeds the polymerization process and rapidly accelerates the curing process, forming tough cross-linked plastic that provides aggressive adhesion with effective shear strength.
More commonly referred to as threadlockers, pipe sealants, retaining compounds, and gasket makers, these adhesives are often used to enhance the seal, or holding force, in the threads of joined fastener systems such as nut-and-bolt assemblies. A nut-and-bolt assembly may have as little as 15% metal-to-metal contact and even a small amount of anaerobic adhesive readily fills any air voids between the threads and then hardens to a thermoset plastic. These unique adhesives are easy-to-dispense, cure rapidly, and provide effective torque strength while resisting temperature and vibration and sealing out moisture and gasses to protect against corrosion. Anaerobic adhesives can decrease manufacturing costs, enhance equipment reliability, minimize aftermarket breakdown, and reduce warranty claims.

3M 22393, Roloc Disc 361F, 36 YF-weight, TR, 3 in, Die R300V, 7000045093
3M 22405, Roloc Disc 361F, P100 YF-weight, TR, 3 in, Die R300V, 7000045102
3M 77154 Scotch-Brite Durable Flex Belt, 1/2 in x 18 in, A FIN, Trial Pack, 7010310032
3M 22404, Roloc Disc 361F, 80 YF-weight, TR, 3 in, Die R300V, 7000045100
Dynabrade 15420 Dynafile III Abrasive Belt Tool
Dynabrade 90875 2" Dia. Super Fine NWN DynaBrite Locking-Type Disc, 25/pack
3M™ 72787, Calibration Kit 529-04-48, Large, 7000052154, 1 EA/Case
Standard Abrasives 42564, A/O Flap Wheel 611403, 1 in x 1 in x 1/4 in 40, 7010310476, 10 per case
Dynabrade 51623 .1 hp Straight-Line Extension Pencil Grinder, Central Vacuum, 1/8" Collet
3M 22394, Roloc Disc 361F, 50 YF-weight, TR, 3 in, Die R300V, 7000045096
3M 97419, Aluminum Foil Tape 3380, Silver, 48 mm x 45 m, 3.25 mil, 7000049613
Dynabrade 77765 4-1/2" Dia. x 7/8" Center Hole, 120 Grit, Type 27, Ceramic DynaCut Flap Disc, 10/pack
Insize 7232, SCRIBER, 6928640320088
3M 77558, Cubitron II Hookit Cloth Disc 947A, 77558, 40+ to 120+, 6 in x NH, Die 600Z, 7100232737
Dynabrade 96101 Dynabrade Air Lube 10W/NR 24 Per Box
3M 10119, Synthetic Steel Wool Pad 10119NA, 0000 Super Fine, 7000126181
Standard Abrasives 42621, A/O Flap Wheel 621406, 1 in x 1 in x 1/4-20 in 80, 7010369106, 10 per case
Dynabrade 51731 .1 hp Straight-Line Pencil Grinder, 60,000 RPM, 1/8" Collet
Dynabrade 92150 1/2" W x 18" L 80 Grit Ceramic DynaCut Scalloped Edge Belt, 50/pack
3M 45714, Cubitron II Hookit Cloth Disc 947A, 120+ X-weight, 3 in x NH, D/F 3HL, Die 300BE, 7100113113
Dynabrade 91429 1/2" W x 12" L 80 Grit A/O DynaCut Belt, 50/pack
3M 71358, 641WY 1/4" X 24", 600 Mesh Diamond Cloth Belt, 7010534894
3M 06524, Scotch Steel Gray Masking Paper, 06524, 24 in x 1000 ft, 1 per case, 7000045442
Dynabrade 95821 Dynabrade Air Lube 10W/NR, 4oz Bottle
3M 62663, Scotch-Weld General Purpose Retaining Compound RT09, Green, 250 mL Bottle, 7010367430, 2/case
Dynabrade 78425 4-1/2" Dia. x 3/8" Coarse DynaBrite Surface Conditioning Disc, 25/pack
Standard Abrasives 700718, A/O Straight Cartridge Roll, 1/4 in x 1-1/2 in x 1/8 in 180, 7100080030
3M 10118, Synthetic Steel Wool Pads, 10118NA, #0 Fine, 7000126148
3M 20886, PSA Cloth Disc 348D, P100 X-weight, 5 in x NH, Die 500X, 7000148148
3M 50010, VentureClad Insulation Jacketing Tape 1577CW-WME, White, 99 mm x 13.7 m, 7010379907
Dynabrade 95544 Gear Grease, 2.5oz. Tube
Standard Abrasives 32905, PSA A/O Disc, 706487, 1 in x NH, 120, 7010331819
ACS CX1250 Diamond Belt, 1/2" X 24" 30u
ACS Diamond Cloth Belt, CX1250 1/4" X 24" 75U
3M 06506, Scotch Steel Gray Masking Paper, 06506, 6 in x 1000 ft, 6 per case, 7000045440
3M 15913, Scotch-Brite Roloc Disc High Strength, TR, 2 in X NH A Medium, 7000000710 
