Today, Unison Tek wants to share with you some small knowledge of metal processing. I hope to share the evolution of metalworking machine tools from the historical context. In fact, he is closely related to the ability of humans to use tools and the degree of industrial development.
Taiwan is a manufacturing company, but there are very few articles about our manufacturing technology. It is a pity. However, there are quite a lot of types, classifications and processes for metal processing.
For example, Unison Tek specializes in CNC lathes, milling machines, punching machines and universal spring machines. Welcome to Taipei to find us.
What is metal processing?
Metalworking is a process technology that processes metal materials into individual parts, assemblies, or large structures. Metalworking parts are required from large ships, bridges, precision engine parts, and fine jewelry.
After the Stone Age of mankind using various ores as tools and weapons, it entered the era of metal processing. For example, prehistoric humans used iron to make most of the tools and weapons of production.
The Shang Dynasty had many rituals made of bronze. Device. Metal processing can be said to be the only way for the evolution of human civilization.
Metal processing from manpower production to machine making history
However, before the industrial revolution, metal processing was still using the stage of manpower processing, for example, using silver to knock out various types of silver tableware; metal casting was also a relatively early technology.
Originally used in the early stages of the industrial revolution, manual parts were still being processed. In the industrial revolution, in order to create a stronger and more powerful steam engine, more stringent tolerances and parts were required, which led the new factory to develop a wide range of machine tools and parts.
Especially in 1775, John Wilkinson developed a horizontal drilling machine to advance the metal machining tolerance to mm mm, successfully solving the key technical difficulties of the Watt steam engine, and making the metal processing technology even higher. In particular, the invention of machine tools enabled machines to make machines, and the era of factory explosions followed.
After the power is universal, the power of the machine tool is provided by the electric motor, which can speed up the processing.
Use metal tools to machine metal parts to improve accuracy and speed.
The machine tool can be divided into: according to the degree of computerization:
(1) Traditional metal cutting machine (complete manual control)
(2) Numerical control NC (no CNC, but automatic control)
(3) Computer numerical control CNC (complete computer control) machine tool.
Machines such as Unison Tek's turning and milling machines are computer numerical control CNC (fully computer controlled) machine tools. The differences between the three models are described below.
(1) Traditional metal cutting machine
The metal to be machined on the machine tool is called a “workpiece”, and the tool used to cut the workpiece is called a tool. The power tool provides power to cause relative motion of the workpiece and the tool, and precisely controls this relative motion to remove unwanted portions of the workpiece.
Advantages: Simple products can be processed, precision requirements are not high, processing can be fast, but some people need to look at the machine. The disadvantage is that each action such as cutting, cutting, drilling is individual work of individual machines, or parts that can only be used for simple modeling and tolerance.
If you are going to make high-precision parts, you must first go to the factory to see if it is a CNC model, and if there is at least 2.5D testing equipment.
(2) Numerical control NC (no CNC, but automatic control)
CNC machine tools are machine tools that can be automatically machined with precise instructions that have been previously edited. In simple terms, numerical control can be used to control some machine processing actions by electronically controlling signals.
A series of instruction codes consisting of characters, numbers, symbols, etc. are input to control various actions of the machine. These instruction codes are converted into two electronic control signals, pulse and ON/OFF. The pulse output signal is used for positioning and feed speed control of the spindle and workpiece.
The ON/OFF output signal performs the following functions: (1) controlling the spindle rotation speed and direction (2) controlling the cutting fluid switch (3) cutting tool selection (4) Others, such as pause, selective pause, automatic clamping and release. Typical CNC machine tool appearance, processing area is located in the machine body.
The emergence of CNC machine tools is also a machine developed to improve precision. When the US produced helicopter propellers in the 1940s, a large number of precision machined parts were required.
The US Air Force commissioned mechanical engineers from all walks of life to find ways. Finally, in 1947, John T. Parsons began using the computerized computing machine's cutting path, and then worked with the Massachusetts Institute of Technology to combine the numerical control system with the Cincinnati milling machine to develop the first NC work machine.
Then in 1958 Parsons and Kearney & Trecker successfully developed a machining center with an automatic tool changer. MIT has also developed APT (Automatic Programming Tools). In 1959, Fujitsu of Japan made two major breakthroughs in numerical control: the invention of the oil pulse motor and the algebraic calculation method pulse tween loop. This speeds up the progress of numerical control.
(3) Computer numerical control CNC (complete computer control) machine tool
Between 1960 and 2000, numerical control systems were extended to other metalworking machines. Until the computer microprocessor is applied to the numerical control, the working machine can be operated not only manually, but also by adding automatic control and greatly improving the function.
Such a system is called computer numerical control (CNC). A fast, multi-axis new machine tool also appeared during this period. In particular, Japan succeeded in breaking the traditional machine tool spindle form, moving the machine tool spindle with a spider-like device, and controlled by a high-speed controller, which is a fast, multi-axis machine tool.
The CNC machine also makes a part, not just the work of the technician, but the programmer is also a big factor.
CNC: Computerized Numerical Control, CNC machine tool controller, read into G-Code to start processing
The CNC program can be divided into main program and sub-program (sub-program). Any part that is repeatedly processed can be written with a sub-program to simplify the design of the main program.
Character (numerical data) → word → single section → machining program.
Just open the notepad in the Windows operating system to edit the CNC code, and the written CNC program can use the simulation software to simulate the correctness of the tool path.
Advantages and Disadvantages of CNC: Compared with traditional machine tools and mass production machines, CNC machine tools are more suitable for the production of small or medium-volume high-quality precision parts, and can also adapt to the production of a variety of different products.
Advantage:
High efficiency, high quality and high yield. This is especially noticeable when the finished product is complex and fine.
Increase working hours and increase machine usage (still unattended after work)
Diversification of processing. Unit costs can be reduced in a small number of different production modes.
The data is easy to store and modify.
If the programming is good, it can be used for machine tools at different time and place.
Produce the same product without redesigning.
Reduce fixtures and fixtures. Therefore, the lead time and preparation time are reduced.
Automatic tool change, feeding, etc., with a higher degree of automation.
"Adaptation Control" maintains the tooling machine in optimal production conditions.
Long tool life.
Advantages of personnel management:
Reduce labor and personnel costs. An operator can operate several machines at the same time.
The processing time and unit cost are easy to control, so the production plan can be effectively mastered and the material can be reduced.
Easy to operate. Once the programming is complete, the operation reduces the reliance on high-tech operators.
Eliminate operator error and increase yield.
Disadvantages:
The initial cost of the CNC machine tool is high.
The programmer must have knowledge of processing, operation, etc.
The equipment is sophisticated and has high maintenance and maintenance costs.
Rely on programmers, mechanical maintenance professionals. Such personnel training is more difficult than the average technician.