Cures Quickly to Seal Hydraulic and Pneumatic Pipes and Fittings
Our 3Mâ„¢ Scotch-Weldâ„¢ 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 3Mâ„¢ Scotch-Weldâ„¢ 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, 3Mâ„¢ Scotch-Weldâ„¢ 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 22409, Roloc Disc 361F, P120 XF-weight, TR, 1-1/2 in, Die R150S, 7000045103
3M 20922, PSA Cloth Disc 348D, 60 X-weight, 1-1/2 in x NH, Die 150S, 7010326528.
3M 22392, Roloc Disc 361F, 24 YF-weight, TR, 3 in, Die R300V, 7000045090
3M 11419, Roloc Disc 361F, P240 XF-weight, TR, 2 in, Die R200P, 7000045105
3M 26022, PPS Series 2.0 Adapter, Type S12, 10 mm Male, 1.0 mm Thread, 7100135943
3M 45557, Cubitron ll Cloth Belt 784F, 60+ YF-weight, 2 in x 72 in, Film-lok, Single-flex, 7010299100, 50 per case
3M 26118, PPS Series 2.0 Adapter, Type S26, 11 mm Male, 1.0 mm Thread, 7100135924
3M 22408, Roloc Disc 361F, P100 YF-weight, TR, 1-1/2 in, Die R150S, 7000045101
3M 50010, VentureClad Insulation Jacketing Tape 1577CW-WME, White, 99 mm x 13.7 m, 7010379907
Dynabrade 51633 .1 hp Straight-Line Extension Pencil Grinder, Central Vacuum, 1/8" Collet
3M 22404, Roloc Disc 361F, 80 YF-weight, TR, 3 in, Die R300V, 7000045100
3M 76783, Cubitron II Hookit Cloth Disc 784F, 120+ XF-weight, 5 in x NH, Die 500X, 7100222757
Dynabrade 95848 Dynabrade Gear Oil
3M 08025, Adhesive Sealant 740 UV, Black, 600 mL Sausage Pack, 7100057385, 12/Case
3M 35827, Hookit Dust Extraction Flexible Sanding Block, 273 mm x 67 mm, 7100256623
3M 11414, Roloc Disc 361F, P120 XF-weight, TR, 1 in, Die R100N, 7000045104
3M 90195, Drywall Pole Sander, DRPS-009, 3.25 in x 8.75 in, 7010370891
3M 27257, Ultra Durable 5 inch Power Sanding Discs, Universal Hole, 180 grit, 7100188462, 5 per pack
3M 64324, Foil Tape 3340, Silver, 72 mm x 45.7 m, 3.9 mil, 7010335734
3M 09099, Scotch-Brite Paint and Rust Stripper Large Area 9099NA, 7010375230 
