PLANT TO CROP HEAD AND TAIL AND TO TAKE SAMPLES

Abstract: Plant to perform cropping and to take samples, which is suitable to crop the head and tail of a rolled product which may travel at high or very high speeds, the head and tail being discharged through an independent discharge conduit (15), the plant comprising at least one flying shears (11) at least for the shearing and correct delivery of the head and tail, the discharge conduit (15) cooperating with a flying shears (18) to take samples, at least one container (19) for the portions collected as samples being located downstream of the sampling flying shears (18).

Description: This invention concerns a cropping plant able to perform the separation of the head and tail portions from a rolled body and to obtain pieces for use as samples. To be more exact, this invention concerns a cropping plant having the additional purpose of obtaining samples, the plant being suitable to process rolled stock travelling even at high and very high speeds. By high and very high speeds are meant speeds of 100-120 metres per second, in the case of rods with diameters of 4 to 8 mm. Cropping plants are known which employ high and very high speed shears (see for example DE-A-2720136). These cropping plants employ very high speed shears able to shear the head and tail of a rolled product while travelling and, at the same time, to ensure the correct placing of the rolled product in the required discharge conduits. No cropping plant is known which is also able to take samples of the product travelling at speed, especially where the rolled stock is travelling at a high or very high speed. EP-A-0 152 122 describes a plant to perform cropping which is suitable to crop the head and tail of a rolled product the head and tail being discharged through an independent discharge conduit, the plant comprising at least one shears at least for the shearing and correct delivery of the head and tail, whereby the discharge conduit cooperates with a second shears to shear the head or the tail into a series of crop ends, at least one container for the crop ends being located downstream of the second shears. This plant cannot perform the crop of a rolled product travelling at high or very high speeds. This problem is solved by a plant according to claim 1. A very high speed flying shears is known which is suitable to shear rolled stock travelling even faster than 100-120 metres per second and having diameters of 4 to 8 mm., this shears comprising two knives with blades able to contrarotate at a pre-set speed at least in the transient period of shearing. Such flying shears is equipped with a guide which is able to move laterally at a pre-set speed and to position itself at a determined position in relation to the circumferential position of the blades. Downstream of the knives of such flying shears is an internal partition located in a conveyor channel; in the shears the speed of lateral movement of the guide and the speed of rotation of the knives are correlated and the lateral position of the guide and the circumferential position of the blades of the knives are strictly interdependent. The partition in such flying shears has its initial portion formed with a rounded ridge lying on a plane located higher than the horizontal plane containing the shearing axis by a value correlated to the diameter of the rolled stock. A shears of this type can be employed to shear the head and tail of the rolled stock where the invention is applied to rolled stock travelling at high or very high speeds. A further flying shears is fitted on the discharge conduit of a flying shears of the type described above, for instance. This further flying shears too may be of the type described above. This second flying shears has the purpose of shearing the terminal portion of the sheared head and the initial portion of the sheared tail and of sending such terminal portion of the sheared head and such initial portion of the sheared tail into a sampling container. The remaining crop ends may be sheared into pieces as scrap or discharged to a zone for scrap. Let us now see with the help of the attached figure, which is given as a non-restrictive example, a preferred embodiment of the invention. The one single figure shows a traditional plant characterized according to the invention and comprising a further flying shears for sampling purposes on the discharge conduit. A cropping plant 10 with a sampling capability is provided downstream of an intake conveyor 21. The cropping plant 10 with the sampling capability comprises a first flying shears 11 with a channel 14 connecting a receiver funnel 16 to a coiling machine 17 and a discharge conduit 15 connecting the funnel 16 to a second sampling shears 18. The first flying shears 11 has an intake drawing unit 12 positioned upstream and an outlet drawing unit 13 located downstream. The first flying shears 11 serves to connect the intake conveyor 21 to the coiling machine 17 after having sheared the head and tail from rolled stock passing through. The head and tail are discharged through the discharge conduit 15. A second flying shears 18 is included downstream of the discharge conduit 15 and serves to shear the terminal portion of the sheared head and/or the initial portion of the sheared tail, thereafter sending such terminal portion and/or initial portion to a sampling container 19, while the remaining portions of the sheared head and tail are discharged or sheared into pieces and delivered to a container 20 for scrap. If so required, any portion of the sheared head and/or tail may be taken as a sample even though the portions indicated above are deemed better. If the first flying shears 11 shears to size the rolled stock after removal of the head and tail, the plant may also be employed to take samples of intermediate portions. The second flying shears 18 obtaining the samples may be of a traditional type.

Claims: Plant to perform cropping and to take samples, which is suitable to crop the head and tail of a rolled product which may travel at high or very high speeds, in the order of 100-120 metres per second, the head and tail being discharged through an independent discharge conduit (15), the plant comprising at least one flying shears (11) at least for the shearing and correct delivery of the head and tail, the plant being whereby the discharge conduit (15) cooperates with a second flying shears (18) to take samples of the terminal portion of the sheared head or/and the initial portion of the sheared tail, at least one container (19) for the portions collected as samples being located downstream of the sampling flying shears (18), while the remaining portions of the sheared head and tail are discharged or sheared into pieces and delivered to a container (20) for scrap, whereby the flying shears (11,18) comprise two knives with blades able to contrarotate at a pre-set speed at least in the transient period of shearing and are equipped with a guide which is able to move laterally at a pre-set speed and to a position itself at a determined position in relation to the circumferential position of the blades. Plant as claimed in Claim 1 which also shears intermediate portions as samples, when the flying shears (11) shears to size the rolled stock after removal of the head and tail.

Inventors: POLONI, ALFREDO
Applicants: DANIELI & C. OFFICINE MECCANICHE S.P.A.
Application year: 1988
Main classification: B23D25
IPC codes: B23D25, B23D31, B23D33