The invention is the application of a new concept of mobile drilling units or drilling machines for drilling profile steel and plate which can be combined more favorably with other machines or installations for sawing, cutting and blasting profile steel and steel plate. Well known is a drilling installation in which a one spindle drilling machine with horizontal centre line (see fig. 1) moves along the material to be drilled. The material on the machine has to be paralleled with the direction of movement of the drilling column (X-direction) against a stop in Z-direc- tion and in X-direction with the head end of the material against a 0-stop present on the drilling installation (in a limited way manually adjustable over 300 mm approx.). Departing from the 0-stop, which is manually adjustable, the drilling unit moves in X-direction and from the base plane in Y-direction and drills the desired holes in the vertical sur- face of the material. This method has the following disadvan¬ tages :

* When it is required to drill holes in more (up to 3) sides of the profile:

- the material has to be tilted (2x) so that you will need a tilting installation and/or crane during the drilling process.

- the drilling machine has to move along the material for each side again (up to 3 times when you need holes at 3 sides).

- the material and the adjustable 0-stop have to be positioned again in X- and Z-direction (up to 3 times) to be able to drill again.

* Installation directly behind and coupling to a sawing machi¬ ne causes problems to undisturbed production and is therefore not desirable, because:

- the adjustable stop for the length measurement (X-direction) is in the way and therefore it is not possible to drill during the sawing process, because the material is not aligned with the Z-axis stop.

- it is impossible to saw during the drilling process.

- the time to process the material is too long because of

tilting and positioning the material in X- and Z-direction and the waiting periods for the sawing and drilling machines would unacceptably decrease the effectively available produc¬ tion-time of sawing and drilling machines. * Coupling a drilling and sawing installation directly behind one another is not advisable because of the problems mentioned above and therefore a separate operator is needed for every machine when the machines need to be productive simultaneous¬ ly, which results in a low saving of labour costs. * Because of the disadvantages mentioned above the drilling machine does not lead to substantial economy in the drilling process and produces too little per time unit, so that the relatively low investment in the machine does not sufficiently come out in the final cost price per ton of produced material. Also known are the stationery 1-, 2- , 3- or multispindle— drillingmachines for profile steel and plate in which the ma¬ terial is guided through the drilling machine and positioned longitudinally in relation to the drilling units by a measu¬ ring device (fig. 2, 3 and 4). Disadvantages of this method are:

- though 3 or more drilling spindles are available their use is restricted, because they are positioned and moving in the same flat vertical area and since the holes in 3 sides of the material are seldom in this one single area, usually only one drilling spindle is active at a time.

- the machine occupies a lot of space in the workshop, because head and rear end of the machine must be available at the maximum length of material to be drilled (fig. 3 and 4).

- that, when a drilling machine is positioned directly adja- cent to a sawing machine in order to save costs by using the same length measuring system, the same inlet and outlet installations for both machines and also by using only 1 operator instead of 2, you cannot drill during the sawing process or that you cannot saw during the drilling process, so that the entire installation can only utilize max. 50% of the actual independent capacities of both machines (fig. 4). Not known is a 1- or multi spindle drilling installation or drilling machine to drill profile steel which has for each side 1 or more drilling heads able to move independen ly or

not independently from each other or able to position themselves in relation to the material, using:

- either a controllable and mobile length measuring stop.

- or a contactless location measuring of the material to position the drilling head(s) in relation to the material.

Likewise, it is not known that the possibilities mentioned earlier are combined with a sawing, cutting or blasting installation or other installation. Also not known is a drilling installation as mentioned earlier which uses hollow drills or hole boring cutters in the mobile drilling units instead of spiral drills.

This invention aims at providing a series of drilling instal¬ lations which by their concept do not possess (according to the installations mentioned earlier that are not known) the above-mentioned disadvantages and objections of known instal¬ lations which offer as stand-alone units a higher production and a lower cost price, whereas the coupling with other in¬ stallations like sawing, cutting and blasting installations provide even more advantages. A further advantage of coupling such a drilling machine to a sawing machine is that substantial savings are made, because:

- the sawing and drilling process can take place simultane¬ ously, so that a high production per time unit is reached.

- the length measuring device of the drilling head(s) can also be used for the sawing machine-.

- 1 operator can simultaneously operate the sawing and dril¬ ling installation.

- the construction of the installation can be cheaper.

This goal is reached by using drilling machines with 1 or more drilling heads which are mobile in relation to the material (with what using spiral or hollow drills or hole boring cut¬ ters you can drill holes in the material), using a controlla¬ ble mobile length measuring stop and/or contactless location measuring of the material, combined or not with other sawing, cutting and blasting installations without being dependent, on a fixed or manually movable length measuring stop. The invention will be illustrated further by fig.l to 8. Fig.5 and 6 show a drilling machine with 1 drilling head that can be positioned in relation to the material.

Fig.7 shows a drilling machine with 3 drilling heads and fig.8 shows a drilling machine with more independently mobile dril¬ ling heads which position themselves in relation to the mate¬ rial. In order to position the drilling heads either a length mea¬ suring stop is used to determine the position of the material in a contactless process or a controllable length measuring stop is used to determine the position of the material. In a combination with a sawing machine or a cutting installa- tion, this position measuring is also used for the sawing or cutting process.

As soon as the material is moving, the new position of the material will be determined by the measuring device and will be used for positioning the drilling heads, sawing machine or cutting machine, or for the location in relation to stationery sawing machines.

One possible execution is shown in fig.5 in which a controlla¬ ble length measuring stop determines the position of the mate¬ rial, and in which the position of the material is used to po- sition the drilling heads. Another possible execution is one in which the mobile drilling column is equipped with a swivel¬ ling stop, which determines the longitudinal position of the material against the head of the material by:

- stopping as soon as the material is touched - or, by taking the material along to the place desired by the movement of the drilling colurtn

- or, by moving the material against the drilling column which at that moment is standing still in order to start the dril¬ ling process as soon as the stop has swivelled away. There are several possible executions to determine the positi¬ on of the material using the contactless measuring device. One possible execution is shown in fig.6, in which a contact¬ less switch, mounted on the mobile drilling column, releases an impulse when the machine is moving along the beginning of the material, thus determining the position of the material in longitudinal direction for positioning the drilling head and processing the material.

Fig.9 shows a plan of a drilling installation according to fig. 8 combined with a sawing machine and a blasting instal-

lation coupled to roller conveyors and cross conveyor devices . In this figure it becomes clear that compared to a conven¬ tional installation like in fig. 3 and 4:

- less floor area is needed resulting in direct cost savings and allowing to fit such an installation in companies having little room available.

- only 1 operator is needed to operate and check the sawing machine, the drilling machine and the blasting machine without affecting the production capacity of the separate units, which in turn provides a considerable and permanent cost saving.

- the material route is shorter and more direct and therefore more surveyable, reducing the loss of energy and time as a re¬ sult of intervening material transport and the cranes present stay available for other duties, which again has a cost saving effect .