Square Tube Equipment

Square tube equipment is a professional mechanical equipment used to produce square tubes. It is widely used in many fields such as construction, machinery manufacturing, automobile industry, furniture manufacturing, etc. The following is an introduction from the aspects of equipment type, working principle, main composition, technical parameters, maintenance, etc.

Equipment type

Cold-bending square tube equipment: metal sheets are gradually cold-bent and deformed through multiple sets of rollers to finally form square cross-section tubes. The square tubes produced by this equipment have high dimensional accuracy and good surface quality. They are suitable for various metal materials such as carbon steel, stainless steel, aluminum alloy, etc., and are currently the most widely used square tube production equipment.

Welding square tube equipment: metal sheets are first processed into strip steel of suitable width through processes such as flattening and stripping, and then the strip steel is rolled into a square tube through a forming machine, and then the weld is welded by welding equipment, and finally the finished square tube is obtained through processes such as sizing and straightening. This equipment can produce square tubes with larger diameters and has higher production efficiency.

Hot extrusion square tube equipment: Put the metal billet heated to a high temperature into the extrusion die, and under strong pressure, extrude the metal billet through the square die hole of the die to obtain a square tube. This method is suitable for the production of square tubes with some special alloy materials or high requirements for tube performance, but the equipment cost is high and the production process is complicated.

Working principle

Cold bending square tube equipment: After the metal sheet is uncoiled on the uncoiler, it is leveled by the leveling machine to eliminate the unevenness of the sheet. Then, the sheet is sent to the cold bending forming unit through the guide device. In the forming unit, the sheet passes through multiple groups of rollers of different shapes in turn and is gradually bent into the shape of a square tube. Finally, the continuously formed square tube is cut off by the cutting machine according to the set length to obtain the finished square tube of the required length.

Welded square tube equipment: First, the strip is uncoiled on the uncoiler and leveled by the leveling machine before entering the forming machine. In the forming machine, the strip is gradually rolled into a square tube through a series of rollers. Next, in the welding area, the butted edges are welded together using high-frequency welding or argon arc welding to form a complete square tube. The welded square tube is calibrated by a sizing machine, straightened by a straightening machine, and finally cut to length by a cutting machine.

Hot extrusion square tube equipment: First, heat the metal billet to a suitable high temperature to give it good plasticity. Then, put the heated billet into the extrusion barrel, and apply huge pressure through the extrusion rod to extrude the billet through a die with a square die hole. The extruded square tube undergoes subsequent processing procedures such as cooling, sizing, and straightening to obtain a finished square tube that meets the requirements.

Main components

Unwinder: used to unwind rolled metal sheets or strips to provide a continuous supply of raw materials for subsequent processing. Unwinders are usually equipped with a tension control system to ensure the stability of the tension of the sheet during the unwinding process to prevent wrinkles or stretching deformation of the sheet.

Leveler: Level the uncoiled plate to eliminate the uneven defects such as wave shape and bend caused by rolling and transportation, so that the plate can enter the subsequent processing smoothly and ensure the quality of square tube forming.

Forming unit: It is the core component of square tube equipment and consists of multiple groups of rollers. For cold-bending square tube equipment, the shape and arrangement of the rollers are designed according to the cross-sectional shape and size of the square tube, and the plate is gradually bent into a square tube through the gradual rolling of the rollers; for the forming machine of the welding square tube equipment, its roller rolls the strip into a square tube.

Welding equipment: It is a special part of the welding square tube equipment. Commonly used welding methods include high-frequency welding and argon arc welding. High-frequency welding has high speed and high production efficiency, and is suitable for mass production of ordinary carbon steel square tubes; argon arc welding has high welding quality and beautiful welds, and is suitable for welding square tubes with high quality requirements such as stainless steel.

Sizing machine: Calibrate the size of the square tube after forming or welding to ensure that the outer diameter, side length and other dimensions of the square tube meet the specified tolerance range. The sizing machine slightly squeezes and shapes the pipe through a mold of a specific shape to improve the dimensional accuracy of the square pipe.

Straightening machine: Eliminate the bending deformation of the square pipe during the forming and welding process, so that the square pipe meets the straightness requirements. The straightening machine generally adopts a multi-roller straightening method. By adjusting the position and pressure of the rollers, the pipe is repeatedly bent and straightened to make its straightness meet the standard.

Cutting machine: Cut the continuously produced square pipe according to the set length to obtain the finished square pipe of the required length. The cutting machine can adopt flying saw cutting, punching and shearing cutting and other methods. Flying saw cutting is suitable for fixed-length cutting on high-speed production lines, and punching and shearing cutting is suitable for cutting small and medium-sized square pipes. It has the characteristics of fast cutting speed and good cutting quality.

Control system: Automatically control the operation of the entire square pipe production equipment, including the start, stop, speed adjustment, fault diagnosis and alarm functions of each part of the equipment. The control system of modern square pipe equipment is usually controlled by PLC (programmable logic controller) or industrial computer, with an intuitive operation interface, which can achieve precise production process control.

Technical parameters

Production speed: The production speed of cold-bending square tube equipment is generally around 5-30 meters per minute, and the specific speed depends on the specifications, materials and equipment configuration of the square tube; the production speed of welded square tube equipment is relatively high, up to 10-50 meters per minute; the production speed of hot extrusion square tube equipment is slow, usually 1-5 meters per minute.

Processing plate thickness: Common cold-bending and welding square tube equipment can process plate thickness ranges from about 0.5 to 10 mm, and different models of equipment can be adjusted according to actual needs; hot extrusion square tube equipment can process a wide range of blank thickness, generally 10-100 mm.

Square tube specifications: The side length of the produced square tube is usually between 10-600 mm, and the maximum and minimum side lengths that can be produced by different equipment are different; the wall thickness range of the square tube is related to the thickness of the processed plate, generally 0.5-10 mm.

Equipment power: Equipment power varies depending on equipment type, production scale and degree of automation. The power of cold-bent square tube equipment is generally 20-100 kilowatts; the power of welded square tube equipment is relatively high due to the inclusion of welding equipment, which is 30-200 kilowatts; the power of hot extrusion square tube equipment is relatively large, which can reach 100-500 kilowatts.