Maximum Strength for Loose-Fitted Parts | Sold as a Case of 24 Bottles

SONLOK 3638 is a fast-curing, high-strength anaerobic retaining compound engineered for permanently securing cylindrical components, especially loose-fitted parts with bond gaps up to 0.25 mm (0.01”). Designed to deliver maximum strength at room temperature, this green retaining compound is ideal for demanding industrial and mechanical assemblies.

Manufactured by Parson Adhesives, SONLOK 3638 is a single-component anaerobic adhesive that cures rapidly in the absence of air when confined between close-fitting metal surfaces. It provides exceptional retaining, sealing, and locking performance with outstanding resistance to heat, vibration, and aggressive chemicals. Supplied in 50ml bottles and sold as a case of 24, it is well suited for production, maintenance, and OEM environments.

Key Features & Benefits

• Maximum-strength anaerobic retaining compound
• Fills gaps up to 0.25 mm (0.01”)
• Fast handling cure for reduced downtime
• Green color for easy visual identification
• Excellent retaining, sealing, and thread-locking capability
• High resistance to heat, vibration, oils, fuels, and chemicals
• Ideal for loose-fitted cylindrical assemblies

Typical Applications

• Locking bushings and sleeves into housings
• Retaining bearings, gears, and collars on shafts
• Cylindrical slip-fit, press-fit, and shrink-fit assemblies
• Industrial machinery and mechanical assemblies
• High-load applications requiring permanent retention

Adhesive Properties

Composition: Urethane Methacrylate
Color: Green
Viscosity: 2,500 cps @ 25°C
(Brookfield RVT, Spindle 4 @ 20 rpm)
Specific Gravity: 1.09
Maximum Gap Fill: 0.25 mm (0.01”)
Flash Point: >93°C
Solvent Content: None
Shelf Life: 1 Year

Curing Properties

Handling Cure Time: ~5 minutes
Functional Cure Time: 1–3 hours
Full Cure Time: 24 hours

Compressive Shear Strength (ISO 10123):
• After 24 hrs @ 22°C (Steel pins & collars):
>25 N/mm² (>4,300 psi)
• After 30 min @ 22°C:
15–17 N/mm² (~2,250 psi)

Service Temperature Range: −55°C to 150°C

Physical Properties

• Coefficient of Thermal Expansion: 80 × 10⁻⁶ (ASTM D696)
• Thermal Conductivity: 0.10 W/(m·K) (ASTM C177)
• Specific Heat: 0.30 kJ/(kg·K)

Chemical Resistance

(% Initial Strength Retained)

Directions for Use

For Assembly

• Clean all surfaces with solvent and allow to dry
• For inactive metals or slow cure, use Activator 3071 or 3049
• Slip fit: Apply adhesive to pin and collar, assemble with rotation
• Press fit: Coat both bond surfaces and assemble quickly
• Shrink fit: Apply adhesive to pin, heat collar, then assemble
• Do not disturb parts until handling strength is achieved

For Disassembly

• Apply localized heat to approximately 250°C (482°F)
• Disassemble while hot

Packaging & Storage

• Package Size: 50ml bottles
• Selling Unit: Case of 24 bottles
• Store unopened containers in a cool, dry place
• Ideal storage temperature: 46°F to 82°F (8°C to 28°C)
• Do not return unused material to original container

SONLOK 3638 Anaerobic Retaining Compound delivers maximum holding strength, excellent gap-filling capability, and long-term durability, making it a trusted solution for permanent retention of cylindrical components in demanding industrial environments—now conveniently packaged in case quantities of 24.