Loctite 638

SKU : 638

Pack Size : 250 ml

10 Piece per Cartoon

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Description

LOCTITE® 638™ is designed for the bonding of cylindrical fitting parts, particularly where bond gaps can approach 0.25 mm and where maximum strength at room temperature is required. The product cures when confined in the absence of air between close fitting metal surfaces and prevents loosening and leakage from shock and vibration. Typical applications include locking bushings and sleeves into housings and on shafts. LOCTITE® 638™ provides robust curing performance. It not only works on active metals (e.g. mild steel) but also on passive substrates such as stainless steel and plated surfaces. The product offers high temperature performance and oil tolerance. It tolerates minor surface contaminations from various oils, such as cutting, lubrication, anti-corrosion and protection fluids

Application

  • Locking and securing components on shafts: This is a primary use, ideal for keeping parts like gears, pulleys, and sprockets firmly in place.
  • Retaining bearings: The compound is excellent for securing bearings in housings or onto shafts, ensuring a 100% contact to prevent corrosion and fretting.
  • Bonding bushings and sleeves: It is commonly used for locking bushings and sleeves into their respective housings or onto shafts.
  • Securing close-fitting cylindrical parts: The adhesive is designed for components with narrow gaps, typically up to 0.25 mm (0.01″).
  • High-strength threadlocking and thread sealing: In demanding environments, it can be used for sealing metal threaded fittings exposed to high pressures or extreme conditions.
  • Assembly of slip-fitted, press-fitted, and shrink-fitted parts: It improves the performance of conventional assembly methods by filling all voids, distributing stress evenly, and enhancing load transmission. 

Direction to Use

For Assembly 1. For best results, clean all surfaces (external and internal)with a LOCTITE® cleaning solvent and allow to dry. 2. To accelerate cure speed or where large gaps are present, use activator and allow to dry. 3. For Slip Fitted Assemblies, apply adhesive around the leading edge of the pin and the inside of the collar and use a rotating motion during assembly to ensure good coverage. 4. For Press Fitted Assemblies, apply adhesive thoroughly to both bond surfaces and assemble at high press on rates. 5. For Shrink Fitted Assemblies, the adhesive should be coated onto the part to produce a smooth, even film of material. If heating the hub for assembly, coat the pin. If the pin is to be cooled for assembly, coat the hub. If both heating and cooling is to be done, apply material to cooled part. Avoid condensation on cooled parts. 6. Parts should not be disturbed until sufficient handling strength is achieved. For Disassembly 1. Remove with standard hand tools. 2. If needed, apply localized heat to the assembly to approximately 250 °C. Disassemble while hot. 3. If this temperature is not possible, heat as much as possible and use mechanical aids. For Cleanup 1. Cured product can be removed with a combination of soaking in a Loctite solvent and mechanical abrasion such as a wire brush.