This article details the key differences between three-roll and four-roll plate bending machines.The core distinctions are that three-roll machines (symmetrical and asymmetrical) are mechanically simpler and more affordable but often require separate equipment for pre-bending plate ends and offer lower automation.In contrast, four-roll machines are fully hydraulic with CNC systems,enabling high automation by performing pre-bending and complete rolling on a single machine.This results in superior processing accuracy,efficiency,and final workpiece quality,though at a higher price point.The choice depends on budget, production needs,and required precision.

This document outlines the composition and key features of an upper-roll universal CNC three-roll plate bending machine, which is based on technology introduced from Japan. The machine's main structure consists of several critical assemblies: the main drive system, which provides forward and reverse working power; the lower rollers and horizontal movement mechanism for feeding and pre-bending plates; the drum-shaped upper roll for deflection compensation; the adjustable support roll assembly; and a tilting mechanism for easy workpiece removal. Key components like the rolls are manufactured from high-grade materials (such as 42CrMo and carbon steel) and undergo heat treatment like quenching and tempering to achieve high surface hardness and durability, ensuring robust performance across various industrial applications.

A plate rolling machine performs continuous bending to form metal sheets into cylinders. While efficient, standard symmetrical three-roll models leave straight "dead edges" on the workpiece, which the pre-bending function is designed to eliminate, streamlining production. This robust machine, built with critical forged steel rolls and a rigid frame, is controlled by a reliable electrical system and is indispensable in key industries like boiler manufacturing, shipbuilding, and petroleum engineering for creating cylindrical components.