What is sheet metal bending : its definition, purpose, working principle, advantages, and applications

• What is sheet metal bending : its definition, purpose, working principle, advantages, and applications
  • Definition of sheet metal bending
  • Working principle of sheet metal bending
  • Complete Sheet Metal Bending Part Manufacturing Process and Work Steps
  • Advantages of sheet metal bending
  • Various types of sheet metal bending techniques
  • Factors affecting the accuracy of sheet metal bending parts
  • Types of materials used in sheet metal bending
  • Applications of sheet metal bending parts
  • What is the difference between sheet metal forming and sheet metal bending?
    • What type of part is called: sheet metal bending?
    • What type of parts are called: sheet metal forming
  • Elimold’s sheet metal bending services
  • in conclusion
  • FAQ

Sheet metal bending is one of the most common sheet metal manufacturing techniques and a fundamental process in metal processing. This is primarily because it allows for the creation of complex shapes and structures using flat metal sheets. This technology is widely used across various industries. This article aims to explore the basic concepts, working principles , advantages , and applications of sheet metal bending . As a business owner who needs sheet metal housing parts , after reading this article, you will understand the basic information about sheet metal bending processes and be able to resolve various communication issues that may arise when undertaking sheet metal bending projects with sheet metal parts manufacturers .

Definition of sheet metal bending

First, let’s talk about what sheet metal bending actually is. It’s a specialized manufacturing process for large electronic product casings and structural components. The main concept is to bend a flat sheet of metal along a straight line until plastic deformation occurs. This technique deforms a flat sheet of metal into a specific angle or curvature. It doesn’t change the thickness of the sheet. Instead, plastic (permanent) deformation is what results in the final shape. Typically, a bending machine or similar equipment applies pressure along a straight axis, bending the metal into a specific angle. Sheet metal bending is usually done by a bending machine with adjustable pressure.

Working principle of sheet metal bending

As mentioned earlier, plastic deformation refers to the stage where a material cannot return to its original state after being subjected to force. This depends on the type of metal used and its elastic limit. Sheet metal bending utilizes this principle. Its basic principle is to use a bending machine, which consists of a lower die and an upper die (called a punch). The punch applies force to the sheet metal, pressing it into the lower die, ultimately obtaining a part of the desired shape.

The principle behind the entire bending process: Applying force to an object, causing it to deform, twist, or bend, is called “bending.” Generally, when a force is applied to an object, it deforms. However, when the force is removed, the object returns to its original shape. Or, if the applied force exceeds the allowable limit, the object will lose its original shape and strength, thus becoming damaged. However, some materials, such as metals and heated resins , deform under force and will not return to their original shape or lose their original strength even when the force is removed. The processing method that utilizes this property of materials is called “bending processing.” Depending on the specific application requirements, sheet metal bending techniques can be varied.

Complete Sheet Metal Bending Part Manufacturing Process and Work Steps

A typical CNC bending operation can be viewed as a meticulously choreographed technical feast , broken down into five seamlessly connected stages:

position	The operator places the sheet metal flat on the lower die and pushes it backward until its edge precisely contacts the back gauge pointer. The position of the back gauge, controlled by the CNC system with micron-level precision, directly determines the flange width.
suppress	The slider drives the upper punch downwards at high speed from the top dead center, automatically switching to the set operating speed when it is only a few millimeters away from the surface to ensure safety and accuracy.
Forming	The punch continues downward at a steady working speed, pressing the sheet metal into the V-groove of the lower die. Plastic deformation begins when the pressure exceeds the material’s yield strength. Depth and pressure are monitored in real time by a CNC system.
Hold and Press	The slider reaches the bottom dead center position calculated by the CNC system and may pause briefly according to process settings (such as bottoming) to ensure accurate angle formation and minimize springback.
return trip	The slider quickly rises to the set safe height or returns to the top dead center, completing one bending cycle. The operator can then safely remove or reposition the workpiece for the next bending operation.

Advantages of sheet metal bending

Sheet metal bending offers numerous advantages, particularly noteworthy due to its excellent manufacturability. Some of these advantages are listed below:

Multifunctionality	Sheet metal bending can produce products with a wider range of shapes and sizes, making it very suitable for various applications.
Cost-effectiveness	For small to medium batch production, sheet metal bending is more cost-effective than other methods such as casting or machining.
accuracy	Because there is no need to connect different surfaces and the finished product is molded in one piece, this process has higher precision.
strength	For structural components such as brackets, bending can increase structural strength.
efficiency	Modern bending machine technology is faster, and automation can significantly shorten production time.

Various types of sheet metal bending techniques

The similarities among different sheet metal bending methods lie in their ultimate goal of transforming a metal structure into the desired shape. However, they differ in their operational procedures. Understanding how to bend sheet metal requires recognizing that factors such as material thickness, bending dimensions, bending radius, and intended use determine the method. Different techniques have varying impacts on the overall effect of the sheet metal bending process. Below are some commonly used sheet metal bending techniques.

Air bending	In air bending, you use a punch to press a sheet of metal into a V-shaped die. However, this process can cause the sheet to not perfectly conform to the die’s shape. This allows you to create shapes more flexibly and better control bending parameters such as the bending angle and radius.
Bottom bend	During bottom bending, the sheet metal is pressed between the punch and the die until it reaches the bottom of the die. This sheet metal bending technique is highly precise, ensuring consistent results. The force applied is greater than air bending but less than embossing bending.
Embossing	In this process, the sheet metal is subjected to significant stamping force exceeding its yield strength on the mold. This forces the sheet metal into the mold, completely filling the cavity. The embossing process gives the sheet metal a shape similar to the mold, with similar bending angles and radii.
fold	In the folding process, a portion of a metal sheet needs to be bent at a precise angle along a straight line. Clamps are typically used during folding, rather than punches and dies. The folding process revolves around the clamping point and can be completed manually or automatically.
curling or flattening	You can use flattening as an auxiliary technique to enhance previous bending operations. For example, you can use flattening to smooth out folds. This is suitable for situations that require multiple folding operations.
Meshing or meshing bending	A tenon bend creates a small bend in metal, called a tenon, which results in offset. This bend allows two metal plates to overlap while remaining flush. It also provides clearance for assembled parts such as fasteners.
Rolling	Roll bending is an ideal process for creating curves, cylinders, or large-radius bends. Roll bending machines are particularly suitable for structural components such as pipes. Roll bending machines can be equipped with three to four rollers.
Rotational bending	In rotary bending, you need to use a rotating die to bend a sheet of metal. Rotary bending can be either standard rotary bending or rotary original bending. The former is used for bending sheet metal, allowing for precise bending while minimizing stress and surface damage.
Three-point bending	Three-point bending technology utilizes controlled force to achieve high-precision bending with a larger radius compared to other methods. It employs a three-point bending machine or press with a punch and a pair of adjustable support anvils.
U-shaped bend	A U-shaped bending machine uses a structure of parallel supports and a bending base to bend sheet metal into a U-shape. The U-shaped bending machine includes a U-shaped die, a punch for performing the stamping, and a bending machine for initiating the stamping process.
Wipe the bend or wipe	In edge bending, you use a set of punches and dies to bend sheet metal along its edge. The die provides a stable surface for the sheet metal and defines the bend location. The punch acts on the sheet metal to form the bend, while the bending machine provides the necessary force.

Factors affecting the accuracy of sheet metal bending parts

There are many factors that affect sheet metal bending. The overall process of sheet metal bending involves multiple factors, some of which are briefly explained below:

Material properties	Metals with good ductility and malleability (such as aluminum and copper) are easier to bend than brittle metals (such as stainless steel).
Mold Design	Factors such as punch angle, die width, and tool direction all affect die design and ultimately the quality of the formed product.
Bending allowance	This is the maximum bending limit that the sheet metal can withstand. This allowance needs to be calculated very precisely because it affects the final product.
rebound	This is a factor primarily influenced by the principle of plastic deformation. When a metal undergoes plastic deformation, it retains its deformed shape; however, during springback, the metal does not reach its plastic limit and instead returns to its original state.

Types of materials used in sheet metal bending

Bending , a sheet metal processing technique, can be applied to a wide variety of sheet materials. However, the choice will vary depending on the required performance and the intended bending method. Typically, bending aluminum, stainless steel, and copper sheets are the most common in manufacturing projects. Below is a list of the various materials we can offer and their common applications.

metal or alloy	grade	Key attributes
aluminum plate	1100, 3003, 5052, 6061	Lightweight, corrosion-resistant, good formability, soft to medium strength, etc.
Stainless steel	304, 316, 410	High strength, excellent corrosion resistance, and heat resistance
carbon steel	A36, 1018, 1045	High toughness, ductility, strength and cost-effectiveness
brass	C26000, C28000	It has good strength, high ductility, and corrosion resistance.
copper	C11000, C12200	Excellent electrical and thermal conductivity,
titanium	Second and third grade	High strength, excellent corrosion resistance and biocompatibility
Nickel alloy	Chromium-nickel-iron alloy 625, Monel alloy 400	It has good thermal stability, corrosion resistance, and strength.
Zinc	Zamak 3, Zamak 5	It has good toughness, high ductility, and high impact strength.

Applications of sheet metal bending parts

Sheet metal bending technology can be applied to many industries. Some examples are listed below:

automotive industry	Bending technology is crucial in the automotive industry, commonly used in the manufacture of automotive components such as brackets, chassis, body panels, and exhaust systems. Its precision ensures parts meet stringent specifications, improving vehicle quality and safety.
Aerospace industry	In the aerospace industry, bending technology is used to produce critical components such as aircraft frames, wing parts, and engine cowlings. By bending aluminum and titanium alloys, precision and reliability are ensured to meet aerospace requirements.
Home appliance industry	Sheet metal bending technology is mainly used in the home appliance industry to produce refrigerator panels, washing machine casings, and air conditioner components. Its precision and flexibility allow metal sheets to be bent accurately to meet design specifications.
Construction industry	In the construction industry, it is used to manufacture structural components and metal parts, such as I-beams and metal floor slabs for building projects.
Furniture manufacturing	In furniture manufacturing, bending is used to create metal frames, supports, and decorative components by bending sheet metal into various shapes and angles to enhance the design and functionality of the furniture.
medical equipment	In the medical device manufacturing industry, bending sheet metal is used to produce precision metal components, improving efficiency and quality to meet the specifications of medical devices. For example, bending machines are used to manufacture components for surgical instruments, diagnostic equipment, and hospital furniture, where precision is crucial to meeting safety and performance standards.
Electronic and electrical equipment	In the electronics industry, it is used to produce precision metal housings and components, such as bent metal sheets for housings and brackets, to ensure equipment functionality and safety.
Defense Industry	In the defense industry, it is mainly used to manufacture high-strength metal plates and alloy components, such as ammunition storage containers, armored vehicles and armor plates, thereby improving the durability and safety of military equipment.

What is the difference between sheet metal forming and sheet metal bending?

Are you unsure whether your part needs to be “shaped” or “bent”? Using the wrong terminology can prevent a part from being shaped at all. Let’s clarify this simple yet important point. Generally, we want to distinguish between the two: “bent” refers to a part changing shape along a straight line, forming an angle or corner. “Shaping,” on the other hand, is a more general term referring to any part that is shaped by external force. A part can be both shaped and bent simultaneously.

Precise communication helps us complete your design in one go. For my clients in Europe and North America, clear communication is key to avoiding costly mistakes and delays.

What type of part is called: sheet metal bending?

You should use the term “bend” when you’re talking about creating simple straight angles on a sheet of metal. I often help clients design brackets, channel steel, and housings. These components are primarily made by bending. If your drawings clearly show angles such as 90 degrees or 45 degrees along a straight axis, then the word “bend” is very suitable for describing the desired operation.

What type of parts are called: sheet metal forming

The term “forming” is more appropriate when the shape of a part is more complex than simple angles. If a part has curves, recesses, or protrusions, more than just bending is required. For example, a car door panel is a formed part. It has complex curves and requires the use of stamping presses and custom molds to manufacture. The term “forming” tells me that the manufacturing process may involve more specialized tools. It has a higher level of complexity than simply bending a bracket.

Elimold’s sheet metal bending services

Are you looking for expertise and state-of-the-art sheet metal fabrication facilities to execute your bending designs? At Elimold, our sheet metal bending service boasts a team of experienced engineers and CNC bending machines to handle your projects. We offer over 50 metal and alloy options. You can choose any sheet metal of a specific grade to meet your needs. Therefore, we specialize in providing dedicated surface treatments for sheet metal bending parts, ensuring the desired aesthetics and finish. So, upload your sheet metal design and request a quote. We will then contact you with detailed and accurate information.

in conclusion

In conclusion, it can be confidently stated that sheet metal bending is a key technology widely used in manufacturing processes. Various improvements are being made in this field worldwide, with the latest advancements including the automation of these processes. This development in sheet metal bending technology can open new avenues for innovation in product design and development. As a manufacturer, this article can serve as a practical guide to sheet metal bending, and it is essential to keep in mind the factors mentioned above that can influence the entire process.

FAQ