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 01328, PSA Cloth Disc 348D, P180 X-weight, 3 in x NH, Die 300V, 7000045068
3M 22392, Roloc Disc 361F, 24 YF-weight, TR, 3 in, Die R300V, 7000045090
Dynabrade 91426 1/4" W x 12" L 80 Grit A/O DynaCut Belt, 50/pack
3M 29611, 641WY 1/4" X 24", 100 Mesh Diamond Cloth Belt, 7010534832
Norton 66261013403 - 3" X 1/2" Extra Coarse Grade Silicon Carbide Bear-Tex Rapid Strip TR Stripping Disc, 10 Each
3M 25705, Scotch-Brite Roloc Surface Conditioning Disc, SC-DR, A/O Medium, TR, 3/4 in, 7000120983, 200/case
3M 11137, Roloc Disc 361F, 50 YF-weight, TR, 1-1/2 in, Die R150S, 7000045094
3M 77157 Scotch-Brite Durable Flex Belt, 77157, 1/2 in x 18 in, A MED, Trial Pack, 7010365702
Dynabrade 13509 Dynastraight Finishing Tool, Rear Exhaust, 6,000 RPM, 5/8" (16 mm) or 1" (25 mm) Dia. Arbor
Standard Abrasives 32985, Aluminum Oxide Overlap Disc, 714721, 60 Grit, 2 in x 8-32 x 2 Ply, 7100116380
3M™ 37018, Supplied Air Respirator Vortex Cooling Assembly V-100/37018(AAD), 70070799013, 1 EA/Case
3M 16553, Scotch-Brite Extra Duty Hand Pad 6444, 6 in x 9 in, 7000028548, 60/Case
3M™ 17379, Versaflo™ Length Adjusting Breathing Tube BT-30, 7100009685, 1 EA/Case
Dynabrade 51622 .1 hp Straight-Line Pencil Grinder, Central Vacuum, 35,000 RPM, 3mm Collet
Dynabrade 95843 Dynabrade Air Lube 10W/NR, 1 Gallon
Dynabrade 11476 Dynabelter Abrasive Belt Tool, Heavy-Duty
Dynabrade 51630 .1 hp Straight-Line Extension Pencil Grinder, Central Vacuum, 1/8" Collet
Dynabrade 51702 .1 hp Straight-Line Pencil Grinder, Rear Exhaust, 60,000 RPM, 3/32" Collet
3M 09548, Scotch-Brite EXL Deburring Wheel, XL-WL, 8S Fine, 6 in x 1/2 in x 1 in, 7000136514
3M 45714, Cubitron II Hookit Cloth Disc 947A, 120+ X-weight, 3 in x NH, D/F 3HL, Die 300BE, 7100113113
Insize 6210-81E, UNIVERSAL MAGNETIC STAND, 6928640358197
Standard Abrasives 32953, PSA A/O Disc, 711880, 2 in x NH, 60, 7010310798
3M 71358, 641WY 1/4" X 24", 600 Mesh Diamond Cloth Belt, 7010534894
3M 77231, Scotch-Brite Roloc Deburr and Finish PRO Unitized Wheel, DP-UR, 2S Fine, TR, 2 in x 1/4 in x NH, 7010365721
Dynabrade 51811 .1 hp Straight-Line Pencil Grinder, Rear Exhaust, 1000,000 RPM, 1/16" Collet
Dynabrade 22093 4-1/2" x 9" Hand Sanding Block
3M 11414, Roloc Disc 361F, P120 XF-weight, TR, 1 in, Die R100N, 7000045104
3M 22408, Roloc Disc 361F, P100 YF-weight, TR, 1-1/2 in, Die R150S, 7000045101
3M 35827, Hookit Dust Extraction Flexible Sanding Block, 273 mm x 67 mm, 7100256623
3M 08025, Adhesive Sealant 740 UV, Black, 600 mL Sausage Pack, 7100057385, 12/Case
3M 17094, Versaflo Hood Assembly with Inner Shroud & Premium Head Suspension S-657, 7000002348, 1 EA/Case
3M 35828, Hookit Dust Extraction Flexible Sanding Block, 406 mm x 67 mm, 7100256624
3M 07414, Hand Sanding Metal Finishing Pad 7414NA, 4.375 in x 11 in, Maroon Medium, 7010315820
Dynabrade 51812 .1 hp Straight-Line Pencil Grinder, Rear Exhaust, 1000,000 RPM, 3/32" Collet
3M 08858 Scotch-Brite Surface Conditioning Belt, 1/2 in x 18 in, A CRS, 7000028455
3M Scotchkote Liquid Epoxy Coating Spray System HSS Mix Nozzle, RightAngle, 7000058900 
