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.

Dynabrade 91428 1/2" W x 12" L 60 Grit A/O DynaCut Belt, 50/pack
3M 24049, Wetordry Cloth Disc 281W, P1000 YF-weight, 8 in x NH, Die 800JM, 7000045052
3M 52750, Particulate Respirator 8211, N95, 7000029720, 80 EA/Case
3M Scotchkote Liquid Epoxy Coating Spray System HSS Mix Nozzle, RightAngle, 7000058900
Dynabrade 11684 Dynabelter Contact Arm Assembly 4" DIA X 5/8" W., 40 Duro Serrated
3M 20903, PSA Cloth Disc 348D, P240 X-weight, 2 in x NH, Die 200P, 7000118877
3M 33349, 641WY 1/4" X 24", 220 Mesh Diamond Cloth Belt, 7010534919
Standard Abrasives 850034, Unitized Wheel Steel Screw Mandrel, 7/8 in x 1/4 in Shank, 7000121879
Dynabrade 51622 .1 hp Straight-Line Pencil Grinder, Central Vacuum, 35,000 RPM, 3mm Collet
3M 13714, Cloth Belt 963G, 80 YN-weight, 2 in x 48 in, Film-lok, L-flex, 7000118462, 50 per case
3M 22970, Disc Holder Adapter 9, 5/8-11 External 3/8-24 Internal, 7000046093
Insize 6315, MICROMETER MEASURING FORCE DETECTOR, 6928640351143
3M 62816, Adhesive Sealant 760 UV, White, 600 mL Sausage Pack, 7000046609, 12/Case
3M 27423, Cloth Belt 340D, 80 X-weight, 6 in x 48 in, Film-lok, Single-flex, 7100231504, 20 per case
3M 10120, Synthetic Steel Wool Pads, 10120NA, #000 Extra Fine, 7000126149
3M™ 17323, Versaflo™ Respiratory Helmet Assembly M-407, with Premium Visor and Flame Resistant Shroud, 7000002395, 1 EA/Case
3M 53914, Performance Plus Duct Tape 8979N Nuclear Red, 48 mm x 54.8 m 12.1 mil, 7000049014, 24/ case
Norton 66261014792 - 2" Medium Grade Aluminum Oxide Bear-Tex Speed-Lok High Strength Maroon TR Non-Woven Abrasive Disc 160 Each
3M 53038, 663FC, 3/8" X 90", 20u, Diamond Trizact Belt 7100205972
3M 15913, Scotch-Brite Roloc Disc High Strength, TR, 2 in X NH A Medium, 7000000710
3M 22407, Roloc Disc 361F, 80 YF-weight, TR, 1-1/2 in, Die R150S, 7000045099
Dynabrade 53270 7" (180 mm) Dia. Right-Angle Disc Sander
Dynabrade 02084 Angle Housing Assembly,Steel, Rear Exhaust
3M 45707, Cubitron II Hookit Cloth Disc 947A, 40+ X-weight, 6 in x NH, Die 600Z, 7100113121
Dynabrade 51629 .1 hp Straight-Line Pencil Grinder, Central Vacuum, 1/8" Collet
Standard Abrasives 541150, Quick Change TS P.A.R.T. #10 Disc Mandrel, 5/8 in TA4 (PILOT), 7000121722
3M™ 72787, Calibration Kit 529-04-48, Large, 7000052154, 1 EA/Case
3M 45718, Cubitron II Hookit Cloth Disc 947A, 120+ X-weight, 5 in x NH, D/F 5HL, Die 500FH, 7100113075
Standard Abrasives 863110, A/O Unitized Wheel, 631, 2 in x 1/4 in x 1/4 in, 7000144629
3M 62606, Scotch-Weld Threadlocker TL42, Blue, 50 mL Bottle, 7100039193, 10/case
3M 07189, Particulate Welding Respirator 8515/07189(AAD), N95, 7000002112, 80 EA/Case
Standard Abrasives 42527, A/O Flap Wheel 623410, 2 in x 1 in x 1/4-20 in 180, 7010368975, 10 per case
3M 71346, 675L, 1" X 120", 125u, Diamond Microfinishing Film Belts, 7010534823
3M 76783, Cubitron II Hookit Cloth Disc 784F, 120+ XF-weight, 5 in x NH, Die 500X, 7100222757
3M 77558, Cubitron II Hookit Cloth Disc 947A, 77558, 40+ to 120+, 6 in x NH, Die 600Z, 7100232737
Dynabrade 56850 5" Dia. Non-Vacuum Dynorbital Supreme Random Orbital Sander, 3/32" Orbit
Dynabrade 95843 Dynabrade Air Lube 10W/NR, 1 Gallon
3M 66631, Cloth Belt 341D, 60 X-weight, 6 in x 48 in, Film-lok, Single-flex, 7000118865, 20 per case
3M™ 94275, Versaflo™ Gold Coated Tinted Over-Visor with UV/IR Protection M-967N, 70071696879, 1 EA/Case
Dynabrade 90211 1/8" W x 18" L 60 Grit A/O DynaCut Belt, 50/pack
3M 45711, Cubitron II Hookit Cloth Disc 947A, 40+ X-weight, 3 in x NH, D/F 3HL, Die 300BE, 7100113118
3M 34784, 663FC, 2" X 48", 20u, Diamond Trizact Belts, 7010509133
3M 33780, 641WY 1/4" X 24", 400 Mesh Diamond Cloth Belt, 7010534915
3M 65033, Scotch-Brite Diamond Wheel, 645DC 6 in x 1/2 in x 1 in, 7010365574, Box of 3 
