Galbiati Group has recently manufactured a multi-spindle drilling machine, with two non-independent fixed spindles, for the manufacture of deep-hole tube plates for tube-bundle heat exchangers, for the nuclear industry. The construction of these machines required significant engineering development to hold the strict tolerances required for this type of application.
The drilling machine in question is equipped with a STS/BTA deep-hole drilling system able to realize deep-hole drilling up to a maximum of 1000 mm, equipped with two fixed spindles that drill simultaneously, up to a diameter of 51.7 mm. Each drilling spindle is equipped with a spindle motor with power up to 22 kW.
This drilling machine with two fixed spindles is manufactured with a front chips discharge channel and hydraulic pipes on the machine to give the possibility of installing the two-unit deep-hole Gundrill drilling system. The conversion from the BTA/STS system to Gundrill takes about 4 working hours.
The two-spindle drilling machine is also equipped with a third drilling and milling spindle, located below the drilling spindles of the BTA/STS system. The third spindle allows additional operations such as milling the workpiece or drilling it using an automatic system for locking/releasing the tool on the spindle.
This milling spindle is very useful for carrying out finishing operations on the tube plates (baffles, grooves, flares, tie-rods), avoiding the use of other machines.
The multi-spindle drilling machine, built and designed by Galbiati, is also equipped with a Siemens Sinumerik 840D digital CNC system, which, combined with HEIDENHAIN linear measuring systems, is placed in a dedicated cabinet and located in a control cabin equipped with independent vertical movement.
The photo below shows the construction of the two-spindle drilling machine in the assembly area of the Galbiati Group workshops.