What size of electric torque tightening wrench is generally used for auto repair?

　　What size of electric torque tightening wrench is generally used for auto repair?

The torque of around 380 to 500 is enough. The screw torque on the car rarely exceeds 500. Just remove the tire screws. In fact, the tire screws are not as tight as Yuanbaoliang screws. The tightest screw on the car is probably the front crankshaft pulley screw. In fact, as long as the electric wrench can reach above 350n.m, it basically meets daily needs. Generally, electric wrenches are used to disassemble and assemble threaded parts and fasteners. Because electric wrenches are fast and have large torque, they can basically be used for daily disassembly and assembly.

Generally, a wrench of about 220n.m is used to disassemble and install tires, and a wrench of about 8-25n.m is generally used to tighten spark plugs. The model is selected according to the bolt.

Small torque wrench 4-20NM

Used for high-precision torque applications such as tightening gearbox filter screws. The gearbox is easy to buckle. Once the preset torque is exceeded, the threaded parts will be damaged.

Medium torque wrench 10-50NM

Used to tighten oil drain screws, spark plugs, oil filters, and brake calipers. If the screws are too strong, the threads will be damaged and it will be difficult to disassemble. In particular, the oil paper filter can easily cause the casing to rupture, and the spark plug buckle will require a higher price.

Large torque wrench 60-300NM

Used to tighten tire screws, ordinary screws 120NM, anti-theft screws 110NM.

How to determine the actual required locking torque?

Users can determine the locking torque according to the design requirements of their own equipment; if there are no design requirements, it is recommended to determine it according to the recommended data in the table.

The specific method is: locking torque = (data in the table) × (70-80)%.

For example: Grade 8.8, M48 bolts, the recommended pretightening torque in the table is 3923N·m, then the actual locking torque is: 3923×80%=3138N·m.