The Plate Bending Machine/Sheet Metal Rolling Machine has a very specific set of strengths, making it ideal for certain materials, thicknesses, and volumes. Choosing the right plate bending machine for your machine shop or sheet metal fabrication business(rolling plate) requires understanding the differences between each one, and their unique characteristics, uses, and advantages. Make the right choice and you’ll be happy, act in haste and you might regret it later.
2-roll bending machines, 3-roll bending machines, and 4-roll bending machines…Three different types of Plate Bending Machines that together fill the needs of industry admirably.
Which is best for your particular needs? It is important to understand what finishing processes you need to perform manually.
Read More: Profile Bending Machines: 3 Types and Top 5 Things To Consider Before Buying
2 Roll Plate Bending Machine
The 2-roll bending machines are not quite as common as 3-roll bending machines and 4-roll bending machines series but if you are working with thin sheet metal they can offer a serious alternative. It is capable of creating cylinder shapes, semi-circles, and other basic curved shapes. One pass bending means impressive efficiency and automation, and has a minimum of flat areas, with minimum interaction from the operator.
Machines consist of two rollers between which the sheet metal is passed, and then the force of the rolling causes the metal to bend into the desired circular shape. Some models do provide the ability to create flanges, but they do not support cones or other detailed geometric shapes.
3 Roll Plate Bending Machine
3-Roll Bending Machines can represent a lower initial investment than their 4-Roll Bending Machines, it can perform the same functions as 2-roll bending machines. The key difference is that, with 3-roll bending, you have greater control over the desired output shape. The most common ones support single-pinch bending functions, which require inserting the sheet metal twice to pre-bend both ends. Flat spots on the leading and trailing edges aren’t as small as the 4-Roll bending machines. So some people wrongly assume that is because they are older technology and less popular these days in comparison.
However, there are also double-pinch models available to make pre-bending processes on both ends easier, faster, and more precise, for a wider range of materials and a greater range of thicknesses, 3-Roll Bending Machines can be the perfect solution. BIT supplies a 3-Roll Bending Machine with CNC control.
4 Roll Bending Machine
The biggest benefit a 4-roll plate bender has over 2-roll and 3-roll bending machines is it makes bending processes easier and simpler. A smaller flat spot and the leading and trailing material edges and much greater suitability to CNC control and that is just the start for the 4-Roll Bending Machine.
These machines are fully capable of performing the same functions as 2 or 3-roll plate rolling machines, hydraulic power delivers bending capacities up to 85mm and widths up to 4100mm. Furthermore, 4 roll benders make it possible to create rectangular and square-shaped output by carefully bending the metal in specific areas as it passes through the machine.
The NC controller takes care of accuracy and throughput volumes meaning high production runs and complex bends are easily and routinely taken care of once programmed. You can even perform operator-controlled bends in the usual way and record each stage via the NC control for future reference.
Why CNC plate bending machine is better?
There are 6 many reasons to consider investing in a CNC plate rolling machine
- Consistent leading and trailing edges
- Consistent accuracy
- Consistent shape production
- Simple development of irregular shapes
- Reliability for both low and high volumes
- Automation in varying degrees
CNC facilitates simple programming and consistency with varying degrees of automation.
The plate is loaded automatically onto the feeding table on fully automated lines. Motorized alignment ensures that the plate is parallel to the roll input, and the material is prebent, rolled, and supported. Then it is auto-ejected and transferred to the welding station.
6 Functions and Require to Consider Before Buying a Plate Rolling Machine
- Pre-bending function, most plate bending machines on the market still require pre-bending, but the straight edge caused by pre-bending is often not what customers need. This problem has been solved with the advent of new steel plate rolling machines that do not require pre-bending and have controllable straight-sided sections.
- NC control, modern production often requires a high degree of automation of equipment, and CNC plate rolling machines are also an inevitable development trend.
- Product accuracy requirements, such as roundness, error, angle, opening size, etc., customers should choose according to their own needs.
- Requirements for safety protection devices. As the safety production specification becomes more and more strict, the requirements for the safety protection of the coiling equipment will inevitably increase.
- Integral structure, simple foundation, easy to move The equipment adopts an integral chassis, no anchor bolts are required, the foundation is simple, and it is convenient to move as a place.
- According to the requirements of the rolling shape, including U-shaped, O-shaped, polygonal, etc., you can choose the required rolling machine according to your own requirements.
Workpieces that need to be bent
The most important thing to factor in is to be realistic. Base your requirements on your day-to-day needs not necessarily your future needs such as;
- Propane Tanks
- “Tin” Cans
- Fuel Tanker Trucks
- Water Tanks
- Heavy Equipment Accessories
Width of plate
The machine rolling width capacity is very important, the overall rolling capacity is determined by the physical length of the roll. Rolling machines are available in a range of widths but consider a machine with a width capacity that would suit 80% of your production. The wider you go in capacity the larger the top will be, the adverse reflection of that is the larger the diameter you will need to be rolling.
The yield strength is the strength of the material you are rolling plate, or better put, the strength of resistance to bending that the material has. The harder the material the higher the yield strength and the larger/stronger the plate roll must be to roll the material. Yield points vary greatly from Aluminum to Stainless and other materials in between. Make sure you know the Yield strength of your material as plate rolls are all offered on a mild steel (30,000 PSI) yield strength rating but can be sized in accordance with your needs.
Grade and quality of material
The material of the sheet to be rolled is a crucial factor that will help determine the design of the rolling plate machine you choose. As such, there are essential factors that manufacturers need to consider when purchasing a metal sheet roller. These include the yield strength, temper brittleness of the metal, and the use of the sheet. Most company capacity charts relate to mild steel rolling/bending specifications. Generally, when rolling stainless steel, you should deduct a third of the capacity but increase the capacity by a fourth when rolling aluminum. The grade of the material will also dictate roll crowning. Stainless steel needs more crowning than mild steel whereas aluminum requires zero crowning. The crowning prevents the barrel effect when rolling a cylinder.
Minimum bending diameter
The minimum bending diameter required can be the key factor when choosing sheet bending rolls. Essentially, the smaller the diameter of the roll, the more pressure you’ll need and thus the more yield in the rolls you will have. As a rule of thumb, the minimum bending diameter on a sheet roll is calculated by the top roll diameter x 1.5. Some CNC machines have the capability of rolling down to 1.2 x top roll diameters. Theoretically, a plate rolling machine can roll material to a diameter of 1.5X the top roll diameter and in some applications even down to 1.3X However this is entirely dependent on the material itself and the capacity of the plate rolling machine you are using.
For you to get the best plate roller machine, you need to know the quantity of your output. This will help you determine the type of plate roll machine that will resonate with these needs.
If medium to large production required electric or hydraulic sheet bending rolls a digital display for roll positions could help speed up your production.
The CNC three and NC or CNC four plate roll bending machines are considered to be the best for massive projects, but they boast distinct operational complexity, accuracy levels, and features. You’ll have to choose whether you’ll prefer the three-roll bending machines which are known for their versatility and affordability, or the four-roll bending machines, which are swift, accurate, and precise.