LOCTITE® 638 is designed for the bonding of cylindrical fitting parts, particularly with narrow bond gaps approaching 0.25 mm. The product cures when confined in the absence of air between close-fitting metal surfaces and prevents loosening and leakage due to shock and vibration. It not only works on active metals but also on passive substrates, exhibiting robust cure performance. The product offers high-temperature performance and good oil tolerance, and tolerates minor surface contaminants.

• Ideal for shafts, gears, pulleys and similar cylindrical parts
• High strength on all metals, including passive substrates (e.g. stainless steel)
• High temperature resistance
• Tolerates minor contaminants, including industrial oils
• DVGW Approval (EN 751-1): NG-5146AR0619