Where Is 5-Axis Better Than 3-Axis?

What are the differences between the 3-axis, 3+2-axis and 5-axis processing schemes we often mention?

3-axis processing method:

3-axis machining is carried out by linear feed axes x, y and Z. Machining features: the cutting tool direction remains unchanged during the movement along the whole cutting path. The cutting state of the tool tip cannot be perfect in real time.

3+2 processing method:

The two rotating axes first fix the cutting tool in an inclined position, and then process it by the feed axes x, y and Z. This kind of machine tool is also called positioning 5-axis machine tool. The rotating work plane in space can be defined by 3+2-axis machine machining (such as rotary head or rotary table). In this work plane, 2D or 3D machining operations can be programmed.

Machining features: the rotation axis always rotates to the position where the machining plane is perpendicular to the tool axis for machining, and the machining plane remains fixed during machining.

5-axis processing method:

5-axis machining consists of linear interpolation movement of feed axes x, y and Z and any five axes of rotation axes a, B and C around x, y and Z.

The tool movement can be optimized along the straight line during the whole machining process. In this way, the best cutting state can be maintained on the whole path

How to embody the advantages of 5-axis machine? Here is an example of processing 28 parts at the same time. Through the design of turntable and fixture, and the combination of three machining surfaces of parts in one machining program in 5-axis machining program, the purpose of reducing cycle time is realized.

The turntable can expand the original processing space through accurate positioning. The well-designed fixture can not only improve the processing efficiency, but also reduce the idleness of the machine, and the operators can draw themselves out of it.

For example, machining the first three faces of parts like the following figure requires a total of 264 seconds for each part if the clamping method of vice is used (excluding the clamping time).

By designing more compact fixtures and making full use of the processing space provided by the turntable, we can have the opportunity to process 28 parts at a time.

In the production of the fixture, an aluminum alloy with a size of 114*114*550mm is selected as the matrix, the positioning pin is selected as the positioning, and the compression fixture with less processing space is selected for faster clamping.

Then mill the four surfaces of the substrate, and process a locating pin hole for each part, two slots for avoiding the empty locking fixture, and two threaded holes for locking. This is all the manufacturing steps.

A complete set of locking pins (including 56 set of locking pins and 56 reusable locking blocks). This fixture design can shorten the original processing time from 264 seconds to 202 seconds (excluding the clamping time). This means that the processing time has been reduced by 23.5%.

Moreover, 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 has been processing without waiting for the frequent clamping of the operator, which will greatly reduce the labor intensity of the operator.