Rolling, roll bending or plate rolling is a continuous bending operation in which a long strip of metal (typically coiled steel) is passed through consecutive sets of rolls, or stands, each performing only an incremental part of the bend, until the desired cross Rolling is ideal for producing parts with long lengths or in large quantities.

Plate roller (Plate rolling machine) is a machine tool for continuous bending of the plate, with the function of rolling O-type, U-shaped, multi-segment R and other different shapes of the plate.The metal sheet can be rolled into a circular, curved and tapered workpiece within a certain range by bending machine.

Plate metal bending using Plate rollers is the preferred technique for any relatively thick metal.

Although plates of various sizes and thicknesses can be used, this is the main manufacturing process for metal curved large plates.

The roll bends are fed using two or three or four rollers and the plate is bent to the desired curvature. The arrangement of the rollers determines the exact bending of the workpiece. Different curves are obtained by controlling the distance and angle between the rolls. The movable reel provides the ability to control the curve.

Plate Roller also been called plate rolling machine or plate bending machine. Plate Roller can be divided into different types due to the use in different industries.From the number of rollers is divided into:

2 Roll Plate Roller

3 Roller Bending Machine

4 Roll Plate Roller

Three-roll bending machine has mechanical and hydraulic type.

Mechanical three-roll bendng machine is divided into symmetrical and asymmetrical type.

The metal sheet can be rolled into a circular, curved and tapered workpiece within a certain range by rolling machine.

Plate roller also been called plate rolling machine or plate bending machine.

From the development of the plate roller, upper roller 3 roller bending machine is the most backward, level down 3 roller bending machine slightly advanced, arc down rolling machine is the most advanced.

These rolls tend to work well in high-volume environments with thin-sheet applications, usually 3⁄16 in. and less. In this setup, a mandrel (also called a spindle pipe) mounted on roll A determines the cylinder radius, so if you need to roll a different radius, you need to change out the mandrel. Once set up, though, operation is simple. You raise roll B against roll A, square the plate against the two rolls, and then execute the rotation.


  • Carbon steels including S275,430B,P265GH,S355
  • Case hardened and tempered steels
  • Copper
  • Duplex & Super Duplex Steels 2205,S31803
  • High Chrome molly material
  • Stainless steels 304L , 316L , 321
  • Specialist steels Hastelloy & Inconel

2 Roll Plate Roller Description:

The upper roller of twin rolls plate bending machine is the rigid metal roller and the lower roller is the elastic roller covered by high strength polyurethane material. It can be adjusted vertically.

When the roller is rotated, the upper roller and the feed plate are pressed under pressure and the elastic layer of the lower roller is pressed into the lower roller to produce elastic deformation.But due to the volume of the elastomer is constant, the pressure pass on all around, and produce high strength, uniform distribution, continuous action of back pressure which forced the plate and the rigid roller stay close continuously, the purpose is to make it rolled into a cylinder with rotation.

The depth of the upper roller, which is the deformation of the elastic layer, is the main technological parameter that determines the bending radius.

According to the experimental study, the greater the reduction, the smaller the sheet metal bending radius, but when the amount of indentation reaches a certain value, the bending radius tends to remain stable, which almost has nothing to do with rolling reduction, this is an important feature of twin roller plate bending technology.

Double roller plate bending rolls mainly aimed at the metal plate with the width of 2000 mm, thickness below 2 mm for round rolling, main apply to batch production of a thin container of household appliances. Generally, it can equip with automatic feeding system and automatic discharging system, with a high degree of automation, and high yield.

2 Roll Plate Roller Features:

High productivity and simple operation

3000-4000 small piece work can be processed per day.

Excellent edge bending, roundness, and cylindrical.

Flat plate, pressed work, work with hole, uneven work can be processed

No scratches on work

aluminum, stainless steel, printed work can be processed.

Automatic deflection stopper

When processing thin and long material by urethane roll, deflection appears on upper roll from pressurizing. Also deflection will be appeared in the center of work where forming pressure is not enough. However ISEL has controlled pressure to push the center of urethane roll by hydraulic system and solved this problem.(PAT.)’

2 Roll Plate Roller Disadvantages:

Due to each change in the diameter of the making parts need to make guide roller wheel, it is not suitable for multi-variety and small-batch production.

It cannot be processed with the thick plate and the maximum thickness of the plate is 6 ~ 9mm.

3 Roller Bending Machine Features:

Can equip with numerical control system with PLC,low requirement for the operatorEasy to use,easy to operate, no cumbersome steps are required; CNC have Clear operation and various bending options,the possibility of error is small

It can bending medium thickness plate without slipping,for the conditions and requirements of the roller, the manufacturer can also provide customers with solutions and methods in the first time.

Machine cleaning is also very convenient,in terms of materials, cleaning and maintenance are very easy, low maintenance rate.

Horizontal feeding,does not need to equip with expensive side push device,able to rolling large angle conical workpiece.

Price below the four roller plate bending rolls with same bending ability.

4 Roll Plate Roller Features:

4 roll plate roller are known for their speed, mainly because the workpiece doesn’t have to be removed before rolling to perform the second prebend. You introduce the plate, and the machine grips it between rolls D and C. Roll A then moves up for the first prebend. The system then forms the cylinder, after which roll B raises up to perform the second prebend.

Adopts a torsion-axis synchronous structure, has high precision and roundness after being rolled up! Hydraulic transmission, compared with mechanical transmission, low noise, compact structure, convenient maintenance and use, environmentally friendly and energy efficient.

Has function of roll round, pre-bending, correct the circle, with coarse leveling function. Can pre-bending and rolling of the end of sheet metal can be carried out on the same equipment, reeling process is completed in one pass, including bilateral pre-bending.Straight plate is short (the precision of the formed part is high.) and the pre-bending effect is good! More suitable for roll cones.

The material plate can be directly shaped and flat on the equipment, and the surface quality of the parts is good.

It can be rolled up in many shapes, including round, curved, conical under certain conditions, etc., to obtain a larger tortuous curvature and a high yield.

Fast, efficient, and easy to operate, requiring only one operator. With automatic alignment and clamping function, the plate will not slide and run off, has anti-overload and hydraulic protection functions.With anti-wear, permanent lubrication-free features.


2 Roller Bending Machine Bending Process

Lower roll pressurized → Feeding work and edge bending → Roll rotates → Lower roll move down and complete

The steel cylindrical bending process by urethane roll is using the performing of lower urethane roll by pressurizing from upper roll (steal). by work is pressed and rotate between urethane roll and upper roll wtih pressure for processing. For changing work diameter size, it required to change upper roll diameter or installing the forming ring.

Urethane, Two Roll

These rolls tend to work well in high-volume environments with thin-sheet applications, usually 3⁄16 in. and less. In this setup, a mandrel (also called a spindle pipe) mounted on roll A determines the cylinder radius, so if you need to roll a different radius, you need to change out the mandrel. Once set up, though, operation is simple. You raise roll B against roll A, square the plate against the two rolls, and then execute the rotation.

3 Roller Bending Machine Bending Process

Driven roller Ⅱ, Ⅲ is driven by motor and reducer, which rotates in the same direction at the same speed (or in the opposite direction).

Because of the friction between the roller and the plate, the plate is driven forward and the roller is rotated.

Adjust the position of the upper roller properly, and the roll of different curvature of the plate can be made.

If the workpiece cannot meet the desired curvature after a rolling process, the upper roller can be reduced properly, and then make the reverse rolling again and again until it is rolled into the desired shape.

As can be seen from the above figure, the three rolls of the symmetrical three roller bending machine are arranged in an isosceles triangle, so in the rolling process, the two ends of the workpiece are bound to leave a straight line.

The length of the straight-line segment is about half the distance of the center of the two lower rollers. This part of the straight line is the place where the roller cannot roll, which is the biggest disadvantage of the symmetrical three-axis roller.

Despite the disadvantages of the symmetrical three roller plate bending machine, it has been widely used because of its simple structure, convenient operation and low cost.

As for the problem of eliminating the straight-line segment, it can be solved by different methods in combination with the specific situation, as shown in the table below.

Elbow pre-bendingThis method uses the die to prebend two ends of the steel plate at the pressure machine to achieve the desired curvature.
Keep allowanceAdd appropriate plate allowance at plate ends. After the two ends roll out a certain length, then cut off the remainder (also known as the straight-line segment).
Add base plate for pre-bendingThis method is performed on the roll machine, as shown in figure 3b.
However, when this method is adopted, the ability of the rolling machine should be fully considered, that is, the sum of the bending force of the work and the required gasket should be less than that of the roll plate machine.

Initial Pinch, Three Roll

One of the most common plate rolling configurations, the initial-pinch system entails introducing the plate to the rolls so that roll A and B grip the part, while roll C performs the first prebend. Next, you turn the material 180 degrees and insert the plate to prebend the other edge. Then, you use all three rolls to close the cylinder.

Double Pinch, Three Roll

In this setup, you first lower roll C and raise roll B, then introduce the plate between A and B. Once the plate is gripped, you raise roll C to form the first prebend. Next, you pass the roll through the machine so that the plate is gripped between rolls A and C, then raise roll B to perform the second prebend. Finally, you position the rolls in a standard pyramid configuration and roll the cylinder.

Double Pinch, Variable Geometry

Unlike any other plate roll type, the variable-geometry variety offers a top roll that is not fixed, but instead moves up and down. In this arrangement, you introduce the plate, and then move rolls B and C horizontally so that roll B is almost directly under roll A. You bring roll A down to form the first prebend on one plate edge, then feed the plate through and move the bottom rolls horizontally so that now roll C is almost completely under roll A. Roll A descends to perform the second prebend. Finally, you position the rolls in a standard pyramid to roll the cylinder.

4 Roll Plate Roller Bending Process

The steel plate is placed between the upper and lower rolls, and the upper and lower rolls sandwich the steel plate.

The one side roll is raised and the steel plate is placed against the side roll to align the sheets.

The roller rotates to bring the steel plate to the pre-bending position, and the end of the plate is at the center line of the upper and lower rolls.

The side roller rises to bend the end of the sheet.

The end curvature is measured, several times, and pre-bent to the desired curvature.

Adjust the side roller position, one side of the roller is lowered, and the other side of the roller is adjusted to the plate.

The roller is rotated and rolled, and the position of the side roller should be adjusted during the winding.

In this position, the other end of the plate is pre-bent and the barrel is formed

Double Pinch, Four Roll

These machines are known for their speed, mainly because the workpiece doesn’t have to be removed before rolling to perform the second prebend.

You introduce the plate, and the machine grips it between rolls D and C. Roll A then moves up for the first prebend.

The system then forms the cylinder, after which roll B raises up to perform the second prebend.


2 Roll Plate Roller Application:

  • Automotive muffler
  • Motor casing
  • Outer cylinder of hot water pot
  • Air conditioning duct
  • Oil filter
  • Concrete pile
  • combustion cylinder of stove
  • Exterior panel
  • Incinerator
  • Fire extinguisher tank
  • Dumper
  • Drum can
  • Boiler tank
  • Solar heating device
  • Compressor tank
  • Agricultural device
  • Pole trance
  • Air filter
  • Coil core

3 Roller Bending Machine Application:

Power plant and reactor construction

Petrol and Offshore (pressure vessels and heat exchanger; Silos and storage tanks; Steel structures for platforms and monopiles )


3 Roller Bending Machine Specification:

ModelPressure(Ton)Max bending thickness(mm)Max rollinglengthmmUpper rollerdiametermmDown rollerdiameter mmRollersdistanceMotor kw
Pre-bendingmmMax bendingmmmmDrivingHydraulicMoving

4 Roll Plate Roller Application:

The 4 roll plate roller is suitable for bending and forming of metal plate,and can do rounding cambering word,and coning work in a certain rang

Four roll plate bending machine has a plate-end pre-bending function,and the width of remaining straight edge is small,and has high word efficiency.

It can do rough plane calibrating of metal plate.

It is ideal bending roll machine for all kinds of metal working industry like energy, transportation ,petroleum, chemical, shipping-building, boiler with high technology, full function, high precision and easy in operation character.

4 Roll Plate Roller Specification:

Model Max.Roll ThicknessMax.RolLwidthUpper roller diamaterSide Roller DiematerMotor


Disregarding the regulations that can be done acting directly on the mechanical parts of the machine on some plate roller ( plate bending machine ), we can distinguish the different controls as:

• Manual control

• Control by programmable positioner

• Control by CNC (Computer Numerical Control)

Manual Control

The manual control is performed acting on buttons, joysticks or foot pedals present on the control panel of the  plate roller ( plate bending machine ).

To each single action executed (pressure of the push button etc..) corresponds a movement of the machine.

The position of the driven movable parts can be referred directly on the machine by rulers or on the control panel by digital display that are receiving the signal from encoders.

Example of control panel for manual control

Control By Programmable Positioner

The programmable positioner is an instrument that allows to store one or more positions of one or more driven movable parts of the section bending machine.

Once stored, the position can be loaded and the movable part will move from the position occupied to the stored position.

This instrument is particularly useful to perform bending works where more passages between the rolls are required, both to guarantee an higher repeatability (doing the regulations manually it is possible to commit come mistakes), and to speed up the operations.

Example of control panel for manual control with integrated programmable positioner

Control By CNC

The numerical control based on computer (CNC) allows to store command sequences that will be later automatically executed by the machine.

The commands can affect all or only some parts of the machine.

The main advantage of this type of control is that, excluding the operator participation to the working phase, a higher repeatability is guaranteed and moreover it is possible also for unskilled people to work with the  plate roller ( plate bending machine ).

The usage of CNC in combination with  plate rollers ( plate bending machines )  allows to obtain bending geometries like:

– Straight parts followed by curves

– Multiple radius curve

– Ellipses



1. The plate roller ( plate bending machine ) must have a person responsible for management.

2. The operator must be familiar with the structural performance and usage of the coiling machine and only operate with the consent of the management personnel.

3. Check the safety device carefully before starting the machine.

4. When operating, it is strictly forbidden to place the hands and feet on the roller and transmission parts and the workpiece.

5. After the work is interrupted, the clutch should be hit to neutral.

6, multi-person collaborative work must be directed by someone.

7. It is strictly forbidden to work overload.

8. The dumping reset of the lifting roller of the upper roller and the balance of the upper roller shall be performed after the main drive is stopped.

9. It is forbidden to pile up workpieces and sundries in the workplace, so as to keep the machine and the site clean at all times.


Generally, the relationship between the operating efficiency and the failure rate of the mechanical equipment and the operator is very close. As an operator of the dangerous equipment, it is necessary to know more about the relevant knowledge in order to effectively avoid some misoperations or accidents due to the operator. The accident occurred. Let us take a look at the safety requirements for the details of the plate roller ( plate bending machine ) operation.

First of all, the operator should arrange the environment around the work before the operation, and maintain a good operating environment. At the same time, the operator must be neat and tidy, avoiding the roll of clothes and the like in the roll during the work. It must be noted that the operator can only stand on both sides of the workpiece to be the most reasonable position. If you want to adjust the roundness of the measurement dimension during the operation, then you must stop the operation and prohibit the operation during the operation. The workpiece must have a certain margin at the end.

The process of measuring the roundness of the dimension prohibits the operator from standing on the rolled cylinder and prohibits standing on the workpiece that needs to be machined. For some workpieces that are difficult to process: thicker, or larger diameter, higher hardness or strength of the raw materials, etc., it should be done through a small amount of work at the same time to achieve the desired effect. For some workpieces with small diameters, they should be placed in the middle of the rolls for rolling.


1. According to the requirements of the machine lubrication diagram, refuel the oil cup lubrication and manual lubrication points as required.

2. The coil is made according to the parameters specified by the plate roller ( plate bending machine ) . The thickness of the coil is 20mm, the maximum length is 2500mm, and the yield limit of the coil material is less than 250Mpa.

3. After the power is turned on, carry out the lifting movement of the lower roller in the forward and reverse directions and the upper roller to check whether the movement is abnormal or not.

4. Operate strictly according to the processing procedure and operation method of the bending plate. When the upper roller is lifted to the limit position, it is necessary to pay great attention to the safe operation of the equipment.

5. When the main drive is stopped, the upper roller can be lifted and lowered, the tilting of the inverted bearing and the lifting of the upper roller.

6. In the course of operation, if irregular noise or impact is found, it should be stopped immediately.

7. The personnel in the operation should coordinate with each other and listen to the command of the person in charge of the coil. Without a password, it is forbidden to start the machine.

8. When carrying out the bending operation, it should be very careful that the hand is pressed by the steel plate and rolled together with the steel plate.

9. When lifting the steel plate or reel with the vehicle, be careful not to collide with the machine. After the completion of the bending plate, the site of the finished material is cleared, and the maintenance work of the equipment is completed, and the power supply is turned off in time.