Folge der Sägebörse auf Twitter Die Sägebörse auf Facebook Die Sägebörse auf LinkedIn

New multicut saw from RSA

Aktualisiert am: 06.01.2006 09:32
Sawing performance up to 5,000 pieces/hour including preparation

With the multicut saw centre RASACUT MC from the company RSA in Germany which can be run with HSS as well as with carbide saw blades, more than 5,000 tube sections per hour can be produced and moreover it is possible to integrate flexibly and into one line follow-up processing procedures, such as deburring, measuring, cleaning, stacking, and packing of the sections. Though the output is high, accuracy and quality of the saw cuts are durably kept. Furthermore the saw and all follow-up processing stations can be quickly reset thus resulting in short ancillary times.

This combined, highly efficient sawing and preparing enables tube suppliers and other users to increase their productivity, to achieve favourable piece costs and so to face the competing tube imports from Eastern Europe and Asia. Users made preliminary calculations of the return on investment (ROI) resulting in excellent payback times. Furthermore, the sawing and preparing centre offers the possibility to increase the added value.

New developments increase sawing performance

The entirely new designed multicut saw RASACUT MC is basing on some especially efficient functional units which have already been proven in other RSA machines. The saw forward feed - equipped with a servo axis - is exemplary. It operates against the power that is produced by a compressed air cylinder and because of that it is free from play. So the precision of the saw cut is increased and vibration is avoided thus improving particularly the working life of carbide blades.

A further example is the linear saw geometry: the saw head moves linearly top down through the tubes. Compared with a curved saw geometry which offers some advantages in case of single cut, due to the linear process the cutting time is reduced by 35 % for a multicut saw. A pre-condition for this solution is the exact centric clamping of the workpiece layer below the centre axis of the saw blade. In this connection the development engineers of RSA have come up with a special idea: an intelligent clamping vice. Both clamping jaws are electromotively moved, the clamping vice computes automatically the correct retention force. The clamping jaws are rapidly moving up to the outer contours of the tube and then are developing at creep speed the optimal clamping pressure, which holds the piece safely without deforming it. This value is saved in the control system of the machine. During the following sawing operation only a minimum clamping jaw pass becomes necessary in order to guarantee a reliable clamping. According to RSA set-up times are greatly reduced, whereas the process and handling security is improved due to the development of a new clamping vice.
The feed gripper is equipped with the same clamping system and is integrated into the sawing module. The traverse is designed in correspondence with the fixed length. Advantage: no re-indexing and consequently fewer ancillary times as well as improvement of precision. Moreover another workpiece layer is fed to the gripper already during the cutting process so that subsequently the gripper can immediately carry out the forward feed.

The multicut saw with a drive power from 5.5 kW or more, a continuous r.p.m. range from 30 up to 250 min-1 and equipped with saw blades of up to 350 mm diameter is in the position to cut round tubes with diameters ranging from 20 mm up to 90 mm in single cut as well as round tubes from 10 mm up to 50 mm diameter in multicut. Square and rectangular tubes can be arranged in layers with a width up to 90 mm. Larger tube dimensions and layers are possible on request. Depending on the workpiece dimensions it is possible to obtain an hourly output of about 5,000 pieces.

Preparation goes along with high sawing speed

According to the specific requirements of the users it is possible to individually integrate or to later on retrofit the saw with further modules for deburring, measuring, cleaning, and stacking of the tube sections without any problems. All modules are unreservedly in the position to process the high output of the multicut saw in one line. So it is possible - in comparison with preparing in independent working stations - to realise considerably reduced piece costs.

After cutting a gripper system takes over the cut fixed length sections and stacks them in the follow-up automatic deburring machine, whereas short and long remnant pieces and trim cuts are automatically ejected. Furthermore the automatic deburring machine singles the tube sections automatically. The deburring station automatically adjusts itself - according to the known saw parameters - to the respective geometrical workpiece characteristics. High performance brushes round off all inner and outer edges of the round, square, and rectangular tubes with a high degree of reproducibility accuracy.

The following measuring module, too, is able to execute a contact-free checking of 5,000 workpieces per hour. An extremely high degree of accuracy is attained, because 2,000 measurements per second are recorded. All measurement results are collected and can be submitted to statistical evaluations such as a Cpk-analyse by means of special RSA software. The measuring module automatically ejects Workpieces being out of the predefined range of tolerance.

Subsequently all dirt particles are removed from the inside and outside of the tube sections by an efficiently working four-stage cleaning process. A constant high-grade cleaning result all over the complete fixed length is ensured which is rounded off by a drying process.

A robot stacking the tube sections into standard containers such as skeleton boxes or europallets or containers designed to user specifications finishes the preparing procedures. The quantity of the stacked tube sections as well as the layer figure within the container can be defined at the central control panel.