1. Working Principle of Threadlocker
Threadlocker is a type of anaerobic adhesive. It cures inside the gap between metal threads without oxygen. It fills thread clearances to prevent loosening caused by vibration, and provides sealing and anti-rust performance. Different strength grades bring different bonding strength, which determines whether you can disassemble the fastener later.
2. Features & Application of Different Threadlocker Grades
2.1 Removable Medium Strength Threadlocker
Medium strength threadlocker is the most universal option. It provides reliable locking after curing, and can be disassembled with standard hand tools. After cleaning residual adhesive on threads, the fastener can be reassembled again. Recommended for positions requiring regular inspection and maintenance: equipment service bolts, general frame fasteners, low-pressure pipe fittings, normal maintenance replacement. Not suitable for heavy load or continuous heavy vibration working conditions without regular access.
2.2 High Strength Permanent Threadlocker
High strength threadlocker forms strong bonding after curing. It cannot be loosened by ordinary wrenches. Heating is normally required to soften the adhesive before disassembly, and thread damage often occurs during removal. It is designed for permanent installation with rare disassembly, heavy load and severe vibration: heavy machinery fixed threads, permanently assembled components, structures with strict anti-loosening requirements and no maintenance plan. Important reminder: Never use high-strength permanent threadlocker on joints that need regular disassembly and inspection, this is the most frequent selection mistake made by customers.
2.3 Low Strength Removable Threadlocker
Low strength threadlocker has low bonding force, which can be separated by simple hand tools. It is mainly used for fine threads and plastic threads to avoid thread locking and stripping, widely used in precision instruments and plastic assemblies.
3. Main Selection Checklist
Confirm maintenance requirement first: choose low or medium strength if disassembly is needed; select high strength only for permanent fixing.
Confirm thread size and material. Primers may be needed for passive metals such as stainless steel and galvanized steel to support curing.
Check working conditions: vibration level, ambient temperature, exposure to oil or chemical liquid.
Check extra requirements such as sealing and leakage prevention.
4. Common Wrong Selections & Consequences
High-strength threadlocker on service joints: impossible to disassemble for repair. Forced removal causes thread stripping or bolt breakage, and parts become scrapped.
Medium-strength threadlocker on heavy vibration / heavy load points: loosening failure happens gradually under long-term vibration and leads to equipment malfunction.
High strength threadlocker on plastic threads: curing stress cracks the plastic base material.
5. Application Tips
Clean oil and dust from thread surface before application. Oil contamination stops anaerobic curing and causes locking failure. Do not apply excessive adhesive to prevent overflow and contamination. Follow the curing time specified by the product datasheet before applying load.
6. FAQ
Q1: Will anti-loosening performance reduce after multiple disassembly of medium strength threadlocker?
A1: The anti-loosening function can be restored after removing old adhesive and reapplying threadlocker. Stable medium-strength grade is recommended for repeated assembly.
Q2: Can fasteners bonded with high-strength threadlocker be removed without damage?
A2: In most cases, heating is required to soften the high-strength anaerobic adhesive before removal. Non-damaged disassembly is difficult. Correct grade selection in advance is the best solution.
