I. Introduction

   Plate rolling machine is a forging and pressing equipment.Plate rolling machine is mainly used in the field of cold machining of industrial containers and pressure tanks, etc.Required molding consistency, arcs are standard, good welding seam connection.Traditionally, industrial containers and tanks are formed by hand - by - hand, step - by - step, experience - operated roller.Due to the increasing demand for natural gas pipelines and oil tankers, traditional production has been unable to meet the requirements of the market.Fully automated machines are needed to realize large-scale industrial production.

II. Process analysis

Plate rolling process is a forming process that USES the plate rolling machine to make continuous 3-point bending of the plate. As shown in figure 1, the plate rolling process is composed of pre-bending -- centering -- coil circle --rounding

1. Pre-bending

  Plate rolling, plate at both ends of a length, because the plate did not contact the roller, not bending, which is called the remaining straight side.In order to avoid the plate from the work roll out, the actual residual straight edge is often larger than the theoretical value.Because the remaining straight edge is difficult to eliminate in the straightening, and causes a large weld stress and equipment load, easy to produce quality and equipment accidents, so the sheet material must be pre-bending the plate edge before rolling, so that the remaining straight edge is close to the theoretical value.

2. Centering

  The purpose of centering is to make the workpiece busbar parallel to the roll axis to prevent the occurrence of skew.

3. Coil circle

  The method of rolling the circle is divided into one feeding and multiple feeding.

The rebound of cold coiling is remarkable, and a certain amount of over coiling is needed.

4. Rounding

  Rounding is generally divided into three steps：

   4.1.Loading.Adjust the roller to the required maximum corrected curvature according to experience or calculation;

  4.2.Rounding.Roll the roller for 1-2 circles under straightening curvature (especially roll near the weld zone), so that the curvature of the whole circle is uniform;

   4.3.Unloading.Gradually remove the load so that the workpiece rolls several times under gradually reduced corrective load.

III.Main structure and work principle

This machine is symmetrical rolling machine, down up roller and then let up and down roller do opposite roll to bend steel plate.

   B. This machine composed of two parts those are working part welded in whole chassis and moving part. Working part composed of left and right bearing base, one up roller, two bottom rollers (the material of the three rollers is 45#steel and do heat treatment), lifting screw and turbine and other accessory parts. Down rollers drive up roller to move, up roller can do up and down move by height way. Drive part composed of main motor, main speed reducer and other accessory parts.

   C. Bottom rollers were drove by main motor through main speed reducer, output spindle of main speed reducer driven to two down rollers by one group gears, the revolve direction of rollers adjusted by main motor.

   D. Upper roll lifted by accessory motor through vice speed reducer drive worm and worm wheel mechanism of right/left rolls bearing base. That to let the lifting pole do up and down move.

   E. Unloading device is designed to remove the workpiece after drums bended into shape. Before unloading the upper rolls move to up limit position, the balance device on upper rolls ends hit upper rolls, draw out the spindle of the pin, then to remove the workpiece.

IV.Technical parameter

1.Universal upper roll rolling machine

2.Asymmetric plate rolling machine

3.Mechanical symmetrical plate rolling machine

4.Horizontal adjustable plate rolling machine

5.Four-rollers plate rolling machine