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 33349, 641WY 1/4" X 24", 220 Mesh Diamond Cloth Belt, 7010534919
3M 62602, Scotch-Weld Threadlocker TL22, Purple, 50 mL Bottle, 7100039159, 10/case
3M 01326, PSA Cloth Disc 348D, P240 X-weight, 3 in x NH, Die 300V, 7000045069
3M 29611, 641WY 1/4" X 24", 100 Mesh Diamond Cloth Belt, 7010534832
3M 08981, Scotch-Weld Epoxy Adhesive DP105, Clear, 48.5 mL Duo-Pak, 7100148733, 12/case
Dynabrade 11486 Dynabelter Accu-Grinder Abrasive Belt Tool, Heavy-Duty
3M 22392, Roloc Disc 361F, 24 YF-weight, TR, 3 in, Die R300V, 7000045090
Dynabrade 64404 36" W x 60" L (914 mm W x 1,524 mm L) Metal Capture Downdraft Table, 230 V (AC), Side Exhaust
ACS Diamond Cloth Belt, CX1250 3" X 90" 20U
3M 54358, Particulate Respirator 8247, R95, with Nuisance Level, Organic Vapor Relief, 7000002060, 120 EA/Case
3M 26557, Cloth Belt 341D, P180 X-weight, 2 in x 48 in, Film-lok, Single-flex, 7010307963, 50 per case
3M 34556, Cubitron II Net Sheet Roll, 320+, 80 mm x 10 m, 7100283765, 6 Rolls/Case
3M 11412, Roloc Disc 361F, 36 YF-weight, TR, 1 in, Die R100N, 7000045092
3M 87449 Silver Depressed Center Grinding Wheel, T27 Quick Change, 9 in x 1/4 in x 5/8-11 Center Hub Thread, 7010409732, 20 per case
3M 66631, Cloth Belt 341D, 60 X-weight, 6 in x 48 in, Film-lok, Single-flex, 7000118865, 20 per case
Dynabrade 14010 Dynafile Abrasive Belt Tool Versatility Kit
3M 33780, 641WY 1/4" X 24", 400 Mesh Diamond Cloth Belt, 7010534915
Standard Abrasives 873273, S/C Unitized Wheel, 732, 6 in x 1/4 in x 1/2 in, 7010301203
3M 20730, PPS Series 2.0 Spray Cup System UV Kit, Standard (22 fl oz,
650 mL), 125u Micron Filters, 7100128906
3M 20907, PSA Cloth Disc 348D, P120 X-weight, 2 in x NH, Die 200P, 7000118875
3M 25678, Scotch-Brite EXL Unitized Wheel, XL-UW, 2S Fine, 6 in x 1/4 in x 3/4 in, 7000120982
3M 82238, Scotch-Weld Epoxy Adhesive 420, Off-White, Part B, 5 Gallon Drum(Pail), 7100001145
3M 66629, Cloth Belt 341D, 40 X-weight, 6 in x 48 in, Film-lok, Single-flex, 7000118863, 20 per case
3M 84159, Microfinishing PSA Film Disc 366L, 40 Mic 3MIL, Type D, 5 in x NH, Die 500X, 7010325504, 500 per case
3M 22409, Roloc Disc 361F, P120 XF-weight, TR, 1-1/2 in, Die R150S, 7000045103
Dynabrade 53270 7" (180 mm) Dia. Right-Angle Disc Sander
ACS CX1250 Diamond Belt, 1/2" X 24" 30u
Standard Abrasives 530205, A/O Resin Fiber Disc, 7 in x 7/8 in 60, 7010310605
3M 76783, Cubitron II Hookit Cloth Disc 784F, 120+ XF-weight, 5 in x NH, Die 500X, 7100222757
3M 71361, 641WY 1/4" X 24", 1200 Mesh Diamond Cloth Belt, 7010534916
Dynabrade 55501 .1hp Pencil Grinder, Twin Turbine, 100,000 RPM, Nickel-Plated Aluminum Housing, 3mm Collet
3M 22397, Roloc Disc 361F, 60 YF-weight, TR, 1-1/2 in x NH, 7000045097
Dynabrade 53244 7" Dia. Type 27 Vertical Depressed Center Wheel Grinder, 3 HP, 7,200 RPM, 5/8"-11 Spindle
3M 22408, Roloc Disc 361F, P100 YF-weight, TR, 1-1/2 in, Die R150S, 7000045101
3M 11419, Roloc Disc 361F, P240 XF-weight, TR, 2 in, Die R200P, 7000045105
3M 05049, Cloth Belt 384F, 80+ XF-weight, 1 in x 30 in, Fabri-lok, Full-flex, 7100141431, 200 per case
Dynabrade 95848 Dynabrade Gear Oil
3M 26172, PPS Series 2.0 6-Pack Starter Kit, Standard (22 fl oz, 650mL), 200 Micron Filter, 7100166584
3M 22404, Roloc Disc 361F, 80 YF-weight, TR, 3 in, Die R300V, 7000045100
3M 94717, Cubitron ll Cloth Belt 947A, 80+ X-weight, 1 in x 30 in, Fabri-lok, Single-flex, 7010294445, 200 per case 
