Some industrial processing procedures that demand high technology and accuracy require laser equipment for operations such as laser cutting, welding, drilling, special machining, material forming etc.
Comparing with traditional oxyacetylene and plasma cutting processes, laser cutting has a lot of advantages, such as faster speed, narrower kerf, smaller heat affected zone, better vertical of slit edge, smoother trimming, and its processing quality is unmatched. Laser cutting is widely used in automotive, mechanical, electrical hardware, aerospace system, transportation, petroleum, elevators, conditioners, switches for electrical appliances, knitting machines, home appliances, grain machines, tools and other fields.
Laser cutting can cut many kinds of materials both metallic and non-metallic. Since the types of material and shape processing are almost unlimited, laser cutting is recognized worldwide as and indispensable basic technology. Laser cutting can get a very high dimensional accuracy and minimal thermal deformation; first-class cutting results are obtained with high efficiency, high accuracy and low cost.
Achieving efficiency and accuracy of laser cutting requires high-end CNC’s with technological features like following control, the optical path compensation, leapfrog, scan cutting, power control, gantry axis control, five-axis interpolation, etc.
Part following control
The purpose of following control is to maintain the distance between the laser cutting head and the work piece constant. Only high-precision, high-dynamic performance of following control, to ensure a smooth and accurate kerf. This reduces workpiece scrap and increases efficiency and cutting speed.
Leapfrog consists in managing the movement between two independent cutting zones. In the past, these movements were made following a rectangular path. The new way of moving is a parabolic path (leapfrog) thatsimplifies programming and reduces the movement time between two points.
Scan cutting is an advanced laser cutting technology. It is mainly used for repetitive operations that require cutting lots of identical profiles. While the axes move at high speed, the laser turns on in the cutting areas and turns off in the transitions between cuts. Thanks to this feature, the processing time of all the cuts is drastically reduced.
Laser power control
Uniform cutting is crucial in a laser cutting process. The longer the part is exposed to laser light, the larger the “burned” area will be. The laser light flow must be adapted to the speed of the axes because if the power of the lase is kept constant for different moving speeds, the resulting grooves will have different widths, consequently damaging the part.
Gantry axis and RTCP
High-end machines usually require functions like Gantry axis for moving heavy laser cutting equipment. Two synchronous drive motors with a single axis ensure high dynamic performance of the entire system.
Also, higher-end laser machines usually cut surfaces that require moving more than three axes at the same time. This type of machines require multi-axis interpolation to keep the orientation of the tip of the laser constant with respect to the part surface. Fagor calls this feature RTCP (Rotating Tool Center Point).
The Fagor CNC 8070 is a point of reference for laser cutting machines in China. The main Chinese manufacturer of this type of machines, Shanghai Unity Prima Laser Machinery Co., Ltd sold 250 laser cutting machines were equipped with Fagor CNC in 2012.