How to disassemble bolts that require high torque?

Firstly, we should fully understand the various characteristics (internal factors) and environmental factors (external factors) of bolts.

The various characteristics of bolts need to be understood by the technical personnel of the bolt manufacturer, including the hardness, strength grade, yield point, elongation after fracture, etc., which should be suitable for the international standard ISO898-1ISO898-2ISO6157-1 and ISO6157-2.

Based on the torque experiment, we recommend that the tightening torque of the bolts be in N.m (Newton meters). The torque value we mentioned here is calculated based on a friction coefficient of 0.14 (new bolts without lubrication without any post-processing), and the data is determined according to the German DIN267 standard quality level.

For M24 bolts: Grade 4.6 (230.5N. m); 5.6 level (308.91N. m); 6.9 level (598.2N. m); Grade 8.8 (711N. m); 10.9 level (1000N. m); Level 12.9 (1196N. m)

M45 bolts: Grade 4.6 (1638N. m); 5.6 level (2177N. m); 6.9 level (4207N. m); 8.8 level (4992N. m); Grade 10.9 (7012N. m); Level 12.9 (8414N. m)

M60 bolts: Grade 4.6 (3932N. m); 5.6 level (5247N. m); 6.9 level (10101N. m); 8.8 level (11964N. m); 10.9 level (116867N. m); Level 12.9 (20202N. m)

External factors affecting bolt torque

Generally, it includes temperature, lubrication, corrosion, whether bolts, gaskets, and reinforcement glue are used, etc.

When facing stubborn bolts, we have the following suggestions: first, lubricate or remove rust on the bolts; It is recommended to use the following tools: tapping wrench, torque wrench, anchor rod torque amplifier, hydraulic wrench.

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