Three Methods for Making Round Tubes with a Bending Machine: Professional Die Selection and Operation Guide

Introduction

In modern manufacturing, bending machines are essential tools widely used in metal processing. They can bend metal sheets into various complex shapes, meeting diverse production needs. Generally, rolling machines are used to make round tubes. However, today we will discuss three solutions for using a bending machine to create round tubes in special cases.

Core Function of Bending Machines

The primary function of a bending machine is to bend metal sheets into the desired shapes using mechanical force. They are extensively used in industries such as construction, automotive, aerospace, and furniture. According to Mordor Intelligence, the global bending machine market is projected to reach about $2.8 billion by 2024, reflecting their importance and growing demand in industrial production.

Article Theme and Purpose

This article aims to introduce three methods for making round tubes with a bending machine. By detailing the required dies, operational steps, and the pros and cons of each method, we hope to help readers choose the best method for making round tubes.

Method 1: Using Standard Bending Dies

Overview

Standard bending dies are among the most commonly used in bending machines, mainly for conventional metal sheet bending. They are simple, easy to operate, and widely applicable, making them ideal for small-batch production of round tubes.

Required Dies

• Standard Bending Dies: Comprising an upper die and a lower die, typically made of high-strength die steel to withstand high pressure and maintain precision.
• Press Head: Used to press the metal sheet into the lower die, shaping it according to the die’s form.
• Die Selection: Choose dies based on the tube’s diameter and thickness to ensure bending precision and consistency.

Steps

1. Preparation
   • Equipment Check: Ensure the bending machine and dies are in good condition, adequately lubricated, and pressure settings are correct.
   • Material Preparation: Select metal sheets suitable for tube making, such as stainless steel, aluminum alloy, or low-carbon steel.
2. Installing Dies
   • Adjust Bending Angle: Adjust the machine’s bending angle and depth according to the desired tube diameter.
   • Install Upper and Lower Dies: Follow the machine’s manual to install and align the dies securely.
3. Bending Operation
   • Position Metal Sheet: Place the metal sheet on the lower die in the correct position.
   • Start Bending Machine: Gradually press the upper die down to bend the sheet into shape.
   • Repeat if Necessary: Repeat the steps if multiple bends are needed until the sheet forms a complete tube.
4. Completion and Inspection
   • Remove Finished Product: Carefully remove the finished tube to avoid damage.
   • Quality Check: Inspect the tube’s dimensions, shape, and surface quality to ensure it meets the requirements.

Advantages and Disadvantages

1. Advantages:
   • Simple operation suitable for most operators.
   • Lower cost, making it ideal for small to medium enterprises.
   • Versatile, suitable for various metals and sheet thicknesses.
2. Disadvantages:
   • Lower precision compared to custom dies.
   • Limited to less complex shapes and specifications.

Method 2: Using Custom Dies

Overview

Custom dies are designed and manufactured to meet specific production needs. They offer higher precision and consistency, suitable for special shapes or specifications required in high-demand environments like aerospace and medical devices.

Required Dies

• Custom Tube Dies: Tailored upper and lower dies made of high-strength alloy steel or other specialized materials to ensure durability and precision.
• Auxiliary Tools: May include special clamps, locators, or other tools for precise positioning and fixing during bending.

Steps

1. Preparation
   • Needs Analysis: Communicate with clients to determine exact tube specifications, materials, and precision requirements.
   • Design Dies: Design dies based on needs using CAD software to create detailed drawings.
   • Manufacture Dies: Produce dies according to the design, ensuring accurate dimensions and surface smoothness, and apply necessary treatments.
2. Installing Dies
   • Install Custom Dies: Align and secure custom dies as per design requirements.
   • Adjust Equipment Parameters: Set the machine’s pressure, angle, and depth according to the tube specifications.
3. Bending Operation
   • Position Metal Sheet: Place the sheet on the lower die and ensure proper positioning with auxiliary tools.
   • Start Bending Machine: Gradually press the upper die down to shape the sheet.
   • Monitor Process: Continuously monitor the state of the dies and material to ensure accuracy.
4. Completion and Inspection
   • Remove Finished Product: Carefully remove the tube.
   • Quality Check: Use precise measuring tools to inspect the tube’s dimensions, shape, and surface quality.

Advantages and Disadvantages

1. Advantages:
   • High precision and consistency tailored to specific needs.
   • Capable of producing complex shapes and special specifications.
   • Increases efficiency in batch production with high quality.
2. Disadvantages:
   • Higher cost for design and manufacturing.
   • Longer production cycle.
   • More complex maintenance requiring professional handling.

Method 3: Using Roll Bending Equipment

Overview

Roll bending equipment is designed to roll metal sheets or profiles into round or arc shapes. Unlike traditional bending machines, roll benders apply continuous rolling pressure, making them suitable for long and large-diameter tubes in industries like construction, energy, and transportation.

Required Dies

• Roll Bending Machine: Core equipment with an upper and lower roller system to adjust the spacing and angle for different diameters.
• Roller Dies: Various sizes of rollers made from high-strength alloy steel to withstand high pressure and long operation times.
• Die Selection: Choose rollers based on tube diameter and material for stable and precise bending.

Steps

1. Preparation
   • Material Preparation: Select metal sheets or profiles like stainless steel, aluminum alloy, or low-carbon steel.
   • Equipment Check: Inspect the roll bender and roller dies to ensure smooth operation and no surface damage.
2. Installing Dies
   • Install Roller Dies: Set up rollers for the required tube diameter and material, adjusting spacing and angle.
   • Equipment Testing: Start the roll bender and test for smooth, even rolling.
3. Bending Operation
   • Position Metal Sheet: Feed the sheet into the roll bender, ensuring it enters the rollers smoothly.
   • Start Roll Bending Machine: Rollers rotate and gradually bend the material into the desired shape.
   • Monitor Process: Continuously check the operation to maintain precision and consistency.
4. Completion and Inspection
   • Remove Finished Product: Stop the machine and carefully remove the tube.
   • Quality Check: Measure the tube’s dimensions, shape, and surface quality to ensure it meets design requirements.

Advantages and Disadvantages

• Advantages:
  • High efficiency for large-scale production.
  • Uniform pressure application ensures high consistency and precision.
  • Wide applicability for various metals and tube diameters, especially large ones.
• Disadvantages:
  • High initial investment and maintenance costs.
  • Requires skilled operation and training.
  • Less effective for small-diameter or complex shapes.

Choosing the Right Method

Based on Production Needs

• Conventional Needs: Standard dies are best for regular production without high precision or complex shapes, offering simplicity and low cost.
• Custom Needs: Custom dies are ideal for special shapes, high precision, or unique materials, despite higher costs and longer cycles.
• Large-Scale Production: Roll bending equipment is optimal for large-scale production, especially for large-diameter or long tubes, providing high efficiency and long-term cost-effectiveness.

Based on Budget

• Low Budget: Standard dies are suitable for small to medium enterprises with limited budgets.
• High Investment Return: Custom dies and roll bending equipment are worth the investment for high-quality products, offering better returns in precision and efficiency.

Based on Production Scale

• Small to Medium Scale: Standard dies fit small to medium batch production due to their simplicity and broad applicability.
• Large Scale: Roll bending equipment enhances production efficiency and consistency for large-scale operations.