Pulling Winch

Pulling winch is a small and light winch device that uses a drum to wind steel wire rope to pull heavy objects. There are two types of pulling winches: electric and hydraulic power winch.

Pulling winch can be used to pull various loads horizontally and diagonally:

• Pulling heavy materials during construction
• Long-distance traction of concrete, steel structure, steel cable, etc.
• Installation and disassembly of mechanical equipment
• Pulling large ships out of the water

The winch must be equipped with at least one brake. The braking torque of the brake should be greater than 1.5 times the static torque at the rated tension of the wire rope. The brake controlled by power must be normally closed.

How do you calculate a winch line pull? Here is an example of a 10 ton winch:

According to the φ28 steel wire rope quality certificate: the total measured breaking force of a single-strand φ28 steel wire rope is 457.66 kN, the minimum breaking force is: 457.66÷9.8×0.82=38.29(t).

Lifting weight of a 10t winch: Q=148.2÷2+0.155+3=77.255t

Calculation coefficient of pulling force of pulley block wire rope running head: f0= fn-1(f-1)/( fn-1)

=1.0417-1(1.04-1)/( 1.0417-1)

=0.079037039

The traction force of the winch wire rope is F=f0KQ

=0.079037039×1.1×77.255

=6.72t

K is the dynamic coefficient

f is the drag coefficient of the pulley

When the stator rises to 9.5m, the angle between the traction wire rope and the pulley block wire rope is:

arctg1/2.4=22.60

Then the safety factor of φ28 steel wire rope is: 457.66÷9.8÷(6.72÷cos22.60)=6.42

Load rate of 10t winch: 6.95÷cos22.60÷10=75.3%.

The winch can either lift or pull a load by means of rope. Some winches can be designed to lift and pull heavy loads and some are designed just to perform pulling function.

• The winch designed for pulling delivers horizontal load movement. In the design of such winch machine, you need to calculate the line pull. The winch for pulling can be fitted with clutch.
• The lifting winches are meant for lifting vertically. They are commonly designed for on land uses.

The pulling or lifting winch is designed for different purposes. Therefore, when selecting a winch product, please consider the task at hand. For example, what is the winch used for? Where will the winch be used? Knowing the purpose of the winch will help you determine the equipment that is suitable for your application.

The direction of the winch wire rope is generally horizontal, and the rope is discharged from the bottom of the drum, so that a relatively small tipping moment can be generated.

However, the rope can also be taken out from other directions. At this time, when the wire rope is inclined, an upward component force will inevitably be generated, which will change the stress state of the anchor bolt. In this case, the specific data of anchor bolt anchoring should be given in the instructions for use.

Regular inspection – The inspection cycle should be determined according to the degree of heavy work of the winch and the harsh environment, but not less than once a month. The inspection includes the following items:

• Any damage and destruction that can be observed during operation and may occur during the inspection period.
• The working performance of the winch and whether the control mechanisms are in good working conditions.
• Check all safety protection devices.
• Check the wear and deformation of each part, especially pay attention to the wear of the wire rope and the fixing of the end.

Periodic inspection – The inspection period should be determined according to the heavy workload and harsh environment, but not less than once a year. Periodic inspections should be recorded and included in the equipment files. The inspection content includes the following items:

• Wear, deformation, cracks, and corrosion of parts.
• Connection of bolts and rivets.
• Whether electrical equipment such as controllers, contactors, switches, buttons, etc. have pitting or abrasion.

Notes When Maintaining:

• Before maintenance, cut off the main power supply and hang maintenance signs.
• All joysticks should be set to the zero position before maintenance.
• The wire rope pulling winch can only be used after all the guards are installed, the safety devices are back to work, and the maintenance equipment is removed.