Positioning control method of strip head in thin strip steel

Abstract

The invention discloses a location control method for a strip head of thin strip steel, and belongs to the technical field of automatic control. The method comprises the following steps: 1) a weldingmachine, a pinch roll device and an optical grating detector are installed, and the pinch roll device comprises an upper press roll, a lower roll, a motor, a motor tail coder, a power cylinder and a lower roll coder; 2) three thickness specification interval sections of the strip steel are divided and input into a main-line PLC, the upper press roll is controlled to fall off by the main-line PLC until the strip steel is clamped between the upper press roll and the lower roll by virtue of a set clamping force separately; and 3) the running speed of the motor is calculated through the motor tailcoder, the strip steel is conveyed at a speed V1, when the optical grating detector detects the strip steel, the strip steel is conveyed at a speed V2, and meanwhile, the lower roll coder installed on the lower roll starts to calculate the length L of the strip steel passing through the optical grating detector, and location for the strip head is completed. According to the method, the distance error of the strip head at a welding stopping position is reduced, so that the compensation accuracy is increased; and the method is completely feasible, and capable of achieving a good effect.

Description

technical field [0001] The invention relates to a thin strip head positioning control method, in particular to a thin strip head positioning control method when the thin strip is welded at a welding machine in a continuous production line, and belongs to the technical field of automatic control. Background technique [0002] According to the applicant's knowledge, in the actual production of the hot-dip galvanizing unit and the hot-dip galvanizing unit in the cold rolling mill, because the product specifications of the galvanizing unit in the cold rolling mill are 0.28 to 1.2mm in thickness and 700 to 1250mm in width, in the production of the above-mentioned When the thickness of the strip steel is thin, the head of the strip steel is carried out on the welding machine for welding positioning, and the positioning is often inaccurate. The time is long and the time is short. It is necessary to cut the head at the welding machine before welding, which is easy Welding failure, r...

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Problems solved by technology

[0004] 1) After the thickness and width specifications of the feeding strip steel change, the feedback value of the encoder deviates from the actual value. The reason is that the thickness of the strip steel specification changes. It is also increasing. When the downforce of the pinch roller remains unchanged, the pinch force of the pinch roller to the strip also increases, the friction between the roller and the strip also increases, and the inertial force of the operation also increases. These points The problem is that the distance from the front grating of the welding machine to the center line of the welding machine is greater than the original actual distance. The frictional force between the steels and the running inertial force are all decreasing, which causes the distance that the strip runs from the front grating of the welding machine to the center line of the welding machine to be smaller than the original actual distance

[0005] 2) In the embodiment, the strip steel thickness is 1.56mm and the thickness of the strip is 1.56mm, and the thickness of the strip is 1.56mm. There is no control method for the welding and positioning of the strip head with a thickness of 0.28 to 1.2mm.

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