The GMW multiwire machine range, represents the excellence in granite and marble sawing thanks to its heavy structure vibrations free, that allows a longer life of the wire, an easy user control system and an unmatched reliability.
GMW Series+ User friendly
In-depth design research
The GMW multi-wire was entirely designed with one of the most advanced 3D CAD systems on the market.
All the important structural components have been designed and verified, both in terms of resistance to the stresses produced during the work phase and to the deformations undergone, through the use of a sophisticated FEM software.
With the use of these design support systems, objectives that were unthinkable with the old methods were achieved, both in terms of optimization of the material for the purpose of stiffness and in terms of final performance of the machine.
Sinergy SKF/Gaspari Menotti
Pulley guiding precision and reliability were the most demanding GMW design challenges immediately. The operating, driving and tensioning system of the diamond wires requires the use of a number of ball bearings equal to the maximum number of wires that can be fitted to each GMW model, plus the same number of bearings that support the tensioning pulleys of smaller diameter, individually operated by a hydraulic actuator and arranged staggered on two axes.
Taking into account the unavoidable clearances, in the axial space of about 20 mm there must be one bearing with a cage, the rolling elements, the two rings and the seals. All in a hostile environment, characterized by the presence of water mixed with granite dust. Furthermore, the presence of hundreds of lubrication points constituted a significant source of costs and an intrinsic limitation for the reliability of the system. The result of this collaboration, with a high technological content, was the definition of a special bearing, characterized by the coupling of the pulley by means of a flange and lubricated with grease for life, exploiting a technology already used in the manufacture of bearings for car wheels.
Simple as a two-columns machine but with the same reliability and rigidity as a four-columns machine
The GMW is designed with a two-column structure in which the cursors that support the arch-shaped cutting frame run.
The driving part consists of a large diameter flywheel, connected to the engine with a special synchronous belt, while the tensioning part is composed of a shaft with idle pulleys and a system of single tensioning pulleys for each diamond wire.
The constructive choice of the two columns allows ease of use and economy in the assembly and disassembly of the wires. The arch structure, made with bent and box-shaped steel plates that give it extreme stiffness, withstands the tension of the diamond wires, leaving only the burden of supporting the cantilevered part on the columns. This solution makes it possible to combine the advantages of two-column machines with regard to ease of use and management of the wires with those of the four-column machines regarding the non-deformability of the system.
For a louger life of the wire
The diamond wire moves around three rollers, a motor drum A, a neutral axis B a tensioning pulley C.
The wire is tensioned diagonally on the pulleys C.
The machine is equipped with a pre-tensioning and a final precision tensioning, both of hydraulic type. This allows:
- longer life of the wire as it is subject to a lower number of bends, thanks to the bigger diameter of the tensioning pulleys, compared to other machines on the market;
- greater cleanliness of the parts suitable for wire tensioning. In fact, the inclined configuration allows better evacuation of dirt;
- greater machine reliability due to the lower total number of bearings and lower stress on the tensioner pulley bearings;
- easy maintenance of the tensioner pulley bearings, which can be simply removed individually.
The frame structure
The structure is made of bent and box-shaped of electro-welded steel plates to achieve maximum rigidity and minimal deformation.
The tensions of the wires both from the motor side and from the tensioner side are discharged, through shaft supports, symmetrically on the structure of the frame, which, thanks to its non-deformability, guarantees absence of vibrations, constancy and precision of tensioning.
The great advantage of this solution consists in the fact that every single diamond wire works in the same tensioning conditions, thanks to the total symmetry of the frame structure, allowing to obtain slabs with constant thickness and excellent surface finish.
The columns are made of electro-welded steel plates with a box-like structure of exceptional rigidity. In the front part there are vertical sliding and rectified steel profiles on which the large cursors slide with adjustable skids in anti-friction material.
The movement takes place through the combined action of an oleodynamic cylinder and a screw-and- nut system with a generous trapezoidal profile, driven by a brushless gear motor and grease lubricated; everything is protected by a bellows. The slide-guide system is lubricated through greasing points located in an easy position directly on the slider.
The whole column-cursor assembly has been studied to guarantee great stability to the machine and continuity of work over time.
The electrical panel board: a concentrate of technology certified industry 4.0
The electrical / electronic system has been designed and built by adopting a FIELD BUS system, with consequent simplification of the wiring, guaranteeing a reduction in the possibility of failures and, possibly, a more rapid and punctual search for them.
Inside there are the best electrical and electronic components in order to guarantee extremely high reliability.
The use of the latest technology follows the guidelines dictated by the canons of “Industry 4.0” so as to make the machine already compatible with future technologies, and translates into greater overall reliability and much faster and safer diagnostics.
Pretensioning of wires
In multiwire machine, for each individual wire, it is essential to guarantee precise, constant and easily manageable tension in the various working phases, so as to make the best use of the cutting and durability qualities of the diamond tool.
Gaspari’s solution includes a double tensioning system.
At first, the GMW performs the general pre-tensioning of the entire idle pulleys assembly, to bring the wires into tension.
The operation is carried out by means of a pair of large hydraulic pistons which, through special wheels with anti-corrosion (stainless) bearings, make the whole structure containing the tensioning pulleys translate upwards on sturdy guides, with diagonal movement.
Quick and precise cutting
Wires tensioning system
Once the general pre-tensioning of the wires has been completed, the final working tension is obtained for each single wire with a single-pulley device, independent of each other, each driven by a hydraulic cylinder.
A hydraulic unit, through a proportional valve, continuously monitors and adjusts the operating pressure of the cylinders in the various work phases. The position of each single pulley is monitored using sensors.
With this system, every single diamond wire is controlled by the management software in each working phase, both in terms of voltage and displacement, thus optimizing the cutting parameters with the variation of the material treated and obtaining remarkable results both in terms of cost and of reliability of the machine-wire system.
Quick guiding liners replacement system
Compared to the other machines on the market, one of the winning features of the GMW is certainly the ease of maintenance, which also includes the replacement of the liners inside which the wires run. Gaspari has studied a solution that allows you to change the polyurethane gaskets in a very short time and with minimal costs. These are strips, on which the single-groove profile is made, placed side by side and fixed on the flywheels (motor drum, tension pulleys, idle flywheels and wire guiding-drum) by pressure fitting according to a suitable design. The flywheel has an outer casing with a series of seats in which the lower profiles of the polyurethane bands are elastically anchored. This solution allows you to easily and quickly replace worn bands without having to disassemble any component of the machine. The possibility of replacing even a single band significantly reduces the maintenance costs of the GMW.
The software: designed to serve the operator
Gaspari has always conceived technology as a useful tool to make available to the customer a huge number of features and potential of the machine, making sure that everything is simple and immediate.
The GMW management software is a concentrate of this philosophy.
The wealth of working parameters under the operator’s direct control is truly impressive, as is the ease with which these parameters can be modified and set both in terms of immediacy and simplicity of the operation through a “touch screen” video system, and also in terms of intuitiveness of the graphics and the logic of “shifting” from one feature to another.
- Remarkable intuitiveness and immediacy
The display with simplified icons and the passage from one function to another using a “touch screen” system allows a great ease of understanding of the functions and an incredible simplicity of use.
- Machine parameters management
All the parameters and data necessary for correct cutting management are continuously monitored and modified by the operator.
- Alarm management and diagnostics
Through a series of sensors and a dedicated software module, all the main functions of the machine are continuously controlled and monitored on video so as to make the processing safe and diagnose problems simple and immediate.
- Statistics management
It is possible to collect and store a considerable amount of information regarding the materials being processed, the production carried out, energy consumption and set speeds, both for statistical purposes of controlling costs, and for being able to create an historical archive continuously updated by the system, which records the optimal cutting parameters for each material. The archive facilitates the use of the machine allowing a standardization of the processes and maximizing the performance of the GMW.
- Remarkable intuitiveness and immediacy