Hydraulic bending machine - modern bending equipmentby Kate Summel Sport
Hydraulic bending machine is used in various manufacturing plants for bending sheet metal using a cold method with strict adherence to the specified bending angles.
How did hydraulic plate bending machines come about?
Initially, the world industry produced mechanical and manual bending machines. They were simple and reliable in operation, had a simple design and did not require excessive costs for their production. It is clear that the manual bending machine did not provide the proper bending accuracy, and to use it, it was necessary to apply considerable physical force. More about bending machine at https://blog.harsle.com/category/press-brake/ The mechanical equipment also had a lot of disadvantages:
high degree of vibration and noise during operation;
low quality of manufactured products;
increased risk of injury to the plant operator;
high consumption of electrical energy;
difficulties, if necessary, changeover of machines.
Simultaneously with mechanical presses, pneumatic equipment began to be used for bending metal blanks. It was operated rather limitedly, since for the operation of such units it was necessary to supply compressed air to them through a special line. And the load force they could provide was comparatively small.
A real breakthrough in sheet metal bending was the appearance in the middle of the 20th century of hydraulic presses, which were distinguished by low electricity consumption, high level of work safety, almost perfect reliability and excellent product quality.
The standard hydraulic press brake has undergone many changes in recent years. Nowadays, it is equipped with innovative devices and mechanisms that greatly facilitate the procedure of bending metal blanks. These include the following devices and developments:
a graphical user interface that allows programmatic control of the machine to independently determine and set the bending sequence;
equipment for adjusting the crosshead speed by electronic devices;
protection of the operator from injury;
bending angle control indicators.
The list of modern additional equipment installed on hydraulic bending machines can be quite long. We will talk about many special mechanisms and intricacies of using CNC sheet bending machines, describing their popular brands.
General information about installations and how they work
The described equipment is usually used in production in the following situations:
to obtain products ideal in terms of quality and accuracy;
as one of the stages in the process of industrial processing of metal blanks with a thickness of 3.5 millimeters;
for fast and inexpensive bending of metal sheets with a thickness of less than 3.5 millimeters;
when performing bending operations of the same type of products (when the tool settings do not need to be changed too often).
Hydraulic bending machines are stationary and mobile. The former are used in one place, they can process large volumes of metal. And the second, mobile, are allowed to be operated at different facilities. As a rule, they are purchased by small manufacturing companies. Both the first and the second at the same time operate on the energy of hydraulic cylinders, which eliminates the need to apply efforts on the part of the bending machine operator.
The essence of the operation of the described equipment is to ensure the set values of the stroke (working) of the installation crosshead and the required effort. A traverse is understood as a rigid steel beam. Devices for specific bending modes are mounted on it, taking into account the characteristics of the workpiece being processed.
The traverse moves under the constant control of special linear sensors. Usually, two pieces are installed on the beams (one "follows" the right side of the beam, the other - the left), which guarantees the evenness of the traverse. In addition, on most bending machines, a programmable back stop is mounted. It allows you to obtain a bendable metal edge with certain geometric values.
Sheet bending machines on hydraulic cylinders are today considered indispensable in the production of materials for hull construction, electronic products, appliances and household appliances, vehicles and special vehicles. They are also required for the manufacture of bent products used in mechanical engineering and machine tool building. When installing additional mechanisms, hydraulic plate bending machines handle cylindrical and conical surfaces of different diameters without problems.
Algorithm of metal bending on sheet bending machines with hydraulic cylinders
The technology of processing sheet metal blanks on the equipment under consideration does not have any particular difficulties. At the same time, it provides the maximum productivity of bending machines and high safety of work.
In general, the process of bending workpieces on the units of interest to us is carried out in seven stages:
The traverse is securely fixed at the so-called "dead top" point.
The traverse is started using a pedal or a control button. The beam moves at the speed planned by the operator from top to bottom. The specified speed is called free fall due to the fact that up to a given moment it is higher than the speed of the bending operation itself. At the same time, it is necessary to understand that there is no really free (that is, uncontrolled) fall as such - the equipment that any modern hydraulic press brake has at its disposal controls every movement of the equipment.
The beam receives the operating speed in the gearshift interval. At this stage, the synchronization of the volume and speed of supply of hydraulic fluid to the hydraulic cylinders, the functioning of the two sides of the traverse and the choice of the planned operating speed is noted. All the sounded processes run simultaneously, hardware adjustments or sensors are responsible for the correctness of their implementation.
The traverse, after obtaining the speed required for work, rushes to another dead point (now to the bottom). In this position, the beam remains for a certain time, which is sufficient to ensure a uniform load on the part subjected to bending.
The traverse begins to be lifted at a clearly marked speed to the value required by the conditions of the technical process. This stage is called decompression. It is controlled automatically, the correctness of the lifting of the beam affects the quality of the resulting product no less than the bending operation itself.
The traverse returns to the dead top point at a sufficiently high speed.
Disconnection of equipment.
Bending machines with additional mechanisms can of course function with some additional steps. But the bending of metal products itself is performed precisely according to the described algorithm.
We add that the processing of workpieces on sheet bending machines with hydraulic cylinders is described by three main parameters - the working length of the machine, the power of the developed load on the part, the productivity for a certain time, as well as several additional characteristics (the distance between the unit racks, the speed of performing working operations, the amplitude with which it can move traverse and others).
Created on Nov 22nd 2020 10:36. Viewed 133 times.