What are the differences between the 3-axis, 3+2-axis, and 5-axis machining solutions we often mention? Let me explain:
3-axis machining
Three-axis machining is performed using linear feed axes X, Y, and Z. Machining characteristics: The cutting tool direction remains constant throughout its movement along the entire cutting path. The cutting state of the tool tip cannot be perfectly achieved in real time.
3+2 axis machining method
Two rotary axes first fix the cutting tool in an inclined position, and then the feed axes X, Y, and Z perform machining. This type of machine tool is also called a positioning five-axis machine tool, and it can be programmed using Siemens' CYCLE800 function. CYCLE800 is a static plane transformation that defines a rotating work plane in space through 3+2 axis machine tool machining (such as a rotary head or rotary table). 2D or 3D machining operations can be programmed on this work plane.
Machining characteristics: The rotary axis always rotates to a position where the machining plane is perpendicular to the tool axis for machining, and the machining plane remains fixed during machining.
5-axis machining
5-axis machining involves linear interpolation motion of any five axes: feed axes X, Y, and Z, and rotary axes A, B, and C around X, Y, and Z. Siemens' TRAORI motion conversion command provides excellent support for 5-axis conversion.
Machining characteristics: The tool direction can be optimized during the entire path movement, while the tool moves in a straight line. In this way, the best cutting condition can be maintained throughout the entire path.
Simultaneous machining of 28 parts on five axes
How are the advantages of a five-axis machine demonstrated? Here's an example of a Haas UMC-750P machine tool simultaneously machining 28 parts. Through the design of the rotary table and fixtures, and by combining the machining of three surfaces of a part into a single machining program within the five-axis machining sequence, cycle time is reduced.
Turntables can expand the original processing space through precise positioning. Well-designed fixtures can not only improve processing efficiency but also reduce machine downtime, freeing up operators from the work.
For example, machining the first three sides of a part like the one shown in the image below would take 264 seconds per part if a vise is used (excluding clamping time).
By designing more compact fixtures and making full use of the machining space provided by the rotary table, it is possible to process 28 parts at once.
In the fabrication of the fixture, an aluminum alloy with dimensions of 114mm*114mm*550mm was selected as the base, a locating pin was selected for positioning, and a clamping fixture that occupies less processing space was selected for faster clamping.
Next, mill the four sides of the base flat, and machine a locating pin hole, two slots for locking the clamps to prevent air leakage, and two threaded holes for locking for each part. These are all the manufacturing steps.
The complete fixture consists of: 28 locating pins, 56 reusable locating locking blocks, 56 screws, and a wrench. This fixture design reduces the original machining time from 264 seconds to 202 seconds (excluding clamping time). This means that the machining time has been reduced by 23.5%.
Furthermore, since the machining program has combined the three machining surfaces of the part into one machining program, the cycle time of a single program becomes 95 minutes. During this period, the machine continues to process without waiting for the operator to frequently clamp the parts, which will greatly reduce the labor intensity of the operator.
