DE1144083B - Method and device for dividing rolled stock, in particular billets - Google Patents

Description

GERMAN

PATENT OFFICE

M 38414 Ib / 49 c

REGISTRATION DATE: JULY 26, 1958

NOTICE THE REGISTRATION AND ISSUE OF THE EDITORIAL: FEBRUARY 21, 1963

Both when subdividing finished products, such as profile bars or the like, and when subdividing of semi-finished products, such as billets, it is common within a rolling program by means of a pair of scissors that can be adjusted to variable cutting lengths, the rolling rod is always the same Divide parts. This means waste because the raw material is never uniform. The dividing of finished products in commercially available lengths is usually imperative while Semi-finished product, e.g. B. billets, therefore divided into equal parts to avoid any further rolling To obtain differences in the lengths of the prefabricated bars. Especially when dividing sticks in always the same lengths, however, the waste that necessarily arises is very significant in terms of weight. In many cases, it could just result in a commercially available length of the finished product. In addition considerable amounts of heat are lost with the pieces of scrap on billet shears. Of the The accumulation of scrap is particularly large in the case of billets because the weight of the raw material is heavy can be different and therefore the same stick length has to be measured in order to be able to use Security to be able to win the specified number of billets from the rolled rod.

Based on the consideration that the scrap waste when dividing rolling stock is zero if one were to divide every rolling rod into exactly the same parts, it would be conceivable measure the length of rolled bars and then with the assumed number of individual bars to determine the same cutting lengths. On a continuous road, however, where the front end of a rolling rod is already in the shears, while the end of the rolling rod is still in the rolling process it does not make sense to measure the total length of the rod because the scissors are too is just behind the last roll stand.

However, in solving the problem, an overall length that differs from the rolling stock in some cases To be divided up without loss, the fact that only individual rods of the same length have to be dispensed with must be dispensed with will. This is consciously accepted, but on the condition that despite less loss Distribution of all individual bars within a certain length tolerance

lie. If this tolerance is not too great, it is entirely acceptable, for example in a

Method and device for dividing rolled stock, in particular billets

Applicant:

Management company Moeller and Neumann

general partnership,
St. Ingbert / Saar, Ensheimer Str. 48

Everard Sigal, St. Ingbert / Saar,
has been named as the inventor

not to roll billets of exactly the same length and feed a finishing train with these billets because the heat and power savings in the lossless splitting in the semi-finished product line outweigh the cutting losses in the subsequent finishing train.
The invention is based on the task of finding a method for subdividing rolling stock, in particular billets, which, taking into account the different overall lengths of rolling rods due to different starting material, also enables the rolling rod to be subdivided without loss of cutting if in the course of continuous rolling the roller rod cannot be measured to a final total length at any point in time so that the cutting device can then still be controlled in variable cycles. Based on the presence of a variable cutting length adjustable device for separating rolling stock, z. B. scissors or saw, a method is proposed according to the invention, according to which each initial cross-section of the raw material is weighed, the total length Lo corresponding to the final cross-section Q is determined from the initial weight G and from this total length Lo the resulting based on the estimated number ρ of the individual sections Length of an individual section is calculated, the number of individual sections being changed if the specified length tolerance is exceeded.
Although the method is intended in particular for dividing billets, it can also be used for finished products, namely when there are no fixed,

309 510/137

commercial lengths of the individual rods are prescribed.

The method according to the invention and a device for carrying out the method are

calculated cut length L in the computing site 40 indicates that the condition L _m i _n <L <Lmax is satisfied, the section length L calculated goes via line 43 to provide feedback to the point 39. If however, with reference to a Ausfuhrungsbeispieles in the drawing 5 is outside the specified tolerance, is assumed by

This is explained in more detail below. It shows

Fig. 1 is a schematic representation of a continuous Rolling train with rotating scissors for dividing the rolling rod into same individual lengths and

Fig. 2 shows the basic circuit of a computing device for determining the respective partial lengths under Consideration of a given tolerance and for controlling the scissors.

With 25 a balance for determining the 15 change in the number of rods ρ by ± 1 come into question, denotes the initial weight of the starting material 26 '. because the raw material is usually not that large

the computing point 40 via the loop 44 a pulse to the point 38 to change the number of cuts p. This impulse is given in the sense and until the change in ρ leads to a rod length L with repeated calculations, which fulfills the mentioned condition. The number ρ is reduced when the calculated cutting length is less than Lmin and is increased when the cutting length is greater than Lmax. Generally only one will

Differences in weight indicate that there is a greater change in the number of rods from the one previously calculated ideal number of rods could be expected.

The measure of maintaining a length tolerance for these by changing the number of individual sections, however, cannot be carried out independently of the tolerance range. For the minimally adjustable The relationship applies to the tolerance range

JL =

Lmin

The starting material is rolled in a continuous rolling train 27 to a final cross-section Q and is to be divided into individual rods 26 so that no cutting loss occurs and the individual lengths of the rods 26 lie within a predetermined tolerance of L _m i _n to L _max. To subdivide the rolling rod, rotating scissors 28 are used to cut rolling stock, which can also be replaced by flying scissors or the like. A photocell 29 gives a signal to switch on the rotating shears 28. 30 and 31 are both tacho dynamos on the last roll stand

as well as on the scissors, partly around the rollers - i.e. the product of the tolerance range and the number of bars speed to determine and on the other hand to a 30 must at least the lower tolerance limit for the Make synchronization of the scissors with the last individual sections of the rolling process. In practice, the scaffolding bring about in a known manner. especially when dividing clubs that are not

In the electrical arithmetic unit according to FIG. 2, certain commercial lengths with a narrow tolerance will have at 32 the initial must determined with the scales 25, rather, further weight G of the starting material will be introduced in its own rolling mill. In its 35 to be processed are the tolerance range, first computing point 33 is derived from the weight G, which is usually given by the furnace dimensions,

and the number of rods is hardly so small that its product is smaller than the minimum length for the individual sections.

The arithmetic operations must occur in the time between the weighing process and the signaling of the Photocell 29 on the roller table behind the last one

and the presettable, reciprocal value of the weight per meter Q- γ of the final cross-section the 1

Product G

Q-Y

formed, where Q is the final cross-section of the rolled rod and γ is the specific weight of the raw material. The reciprocal value is formed in the position 34, with the means of the manually adjustable devices 35 and 36 the

Finishing scaffolding is arranged by the rod front end have expired. The arithmetic operations are

Individual values Q and γ can be preset as required. The 45 initiated by the starting weight G. Beim

The result from the arithmetic station 33 is the total passage of the front end of the rod at the photocell 29

rod length Lo, which gives a second computing station 37 a pulse via a connection 29 '

is forwarded. to the point 39 in order to pass on the here determined

In this second arithmetic station 37, the final cutting length L is sent to the scissors control

Divide the total length La by that in the 50 cause.

Point 38 preselectable number of individual sections ρ from the set the cutting length L order of the calculated cut length L. The total length L ₀
is, by the way, only an imaginary quantity, since it is at
continuous rolling and installation

the shears 28 shortly after the roller train does not appear.

In order to determine whether the cut length L calculated in 37 and fed to the point 39 is within
the predetermined tolerance of Lmin to L is _ma x,
the ascertained 60 is formed in a third computation point 40, which defines the rod throughput time or the cut-to-cut length L with pre-settable extreme values following time T.

Lmin and Lmax compared, whereby from this point the exit velocity ν is determined from the from

a pulse to change the number ρ of the individual tacho dynamo 30 measured roller speed in

sections is given as long as the determined position 46 taking into account a setting

Cutting length L outside of the set extreme constants Jv determined for the advance,

values lies. The cutting sequence time T becomes the cuts of the

The extreme values are on the setting devices 41 influencing the rotating scissors pulse generator 48,

and 42 can be preset. If the comparison in that of the for the first cut at the moment of the signal

To control rotating scissors 28, the cutting length L needs to be converted into a cutting sequence time T.

To this end, in a fourth location 45 of the computing device from the specified cut length L and the measured outlet velocity is ν of the roll bar from the last finishing stand, the quotient -

If the photocell 29 would give an adjustable time AT from the setting device 50 to compensate for the path of the front end of the rod from the photocell to the scissors, the cutting sequence time T would be added. From the moment the signal is given by the photocell 29, the point 48 only sends a cutting impulse via the line 49 to the scissors 28 after a time of T + AT has elapsed , the added ι value AT is deleted via a feedback line 51 from the scissors by a pulse after completion of the first cut at point 48, so that from then on cutting pulses are given at the rate of time T. AT can be deleted , for example, by subtracting the same value AT as it was added before, under the influence of the feedback via 51. The value AT is deleted until the impulse is interrupted due to the delayed loss of the photocurrent after = "the rear end of the rod has passed the photocell 29. Then the point 48 delivers a pulse again in the next first cut Time T -r AT after the signal from the photocell.

In Fig. 1, the routes associated with the times T = L and AT are shown. If the distance of the photocell 29 from the scissors 28, which corresponds to the time AT , is greater than the rod length L or the cutting sequence time T, the photocurrent must also be maintained for a time T after passing the end of the rod, i.e. its elimination, for example by a time relay be delayed so that the deletion of AT is retained in the point 48 and a last cutting pulse is given, since the pulse generator 48 only delivers pulses when a photocurrent is present. Synchronization of the shears 28 with the roll speed of the last stand is ensured via the line 52.

4, j

example

A billet with a finished cross-section = 80 × 80 [mm ² ] and a specific weight γ = 7.85 [kg / dm ³ ] should be divided into equal lengths L without loss of cutting, with the tolerance condition

JL = L _mnj: - Lmin = 10.2 - 9.5 = 0.7 [m]

given is. The constants for Q, γ, L _ma x and L _m in as well as an estimated number of rods /? = 10 are set on devices 35, 36, 41, 42 and 38.

A weight of the primary material G = 5300 [kg] is measured by the scales.

In 33 the total rod length becomes

= 106 [m]

over 44 at 38 enlarged by 1 to p ' = 11, whereby in 37 a new cutting length after

L ₀ 106

L "=

= 9.65 [m]

ρ '- ii

is calculated, which is within the tolerance. If the rolling speed ν = 2 [m / s] is measured, the cutting sequence time T is calculated in 45 as

T = ^ = ^ ' = 4 83 [si.

It is assumed that the photocell 29 lies in front of the scissors 28 by Lf = 13 [m].

With a constant rolling speed v = 2 [m / s] then the time constant for the path of the rod tip from the photocell to the shears is

JT = ψ = 6.5 [s],

which was previously calculated and set at 50. The first cut will

Tt J7 = 4.83 - 6.5 = 11.33 [s]

mentioned later, when the front end of the rod passes the photocell 29, from then on by deleting JT the cutting impulses follow at a rate of 4.83 [s]. With the last cut, the rear end of the rod has already passed the photocell 29, since Lf> L " , namely by 13 - 9.65 = 3.35 m. The corresponding time is

3 ^ 5 AIS

calculated. Q · γ with 50 [kg / m] is the weight per meter of the stick.
In 37 the preliminary cutting length is shown with

τι

L =

106 in r ! - ". Ι

= _w = 10.6 [m]

calculated. In 40, by comparing the size, it is determined that L 'is greater than L _max , that is to say is too large. The number of bars ρ is then given by a command. At least during this time, a time relay must ensure that the signal voltage in the line from the photocell to the pulse generator 48 is maintained so that the last cut is still triggered.

The above-described arithmetic operations can all be performed with known elements of the Electronics or mechanically by means of gear technology elements.

Claims (4)

PATENT CLAIMS: 1. A method for subdividing rolling stock, in particular billets, by means of a cutting device adjustable to variable cutting lengths, characterized in that each initial cross-section of the raw material is weighed, the total length corresponding to the final cross-section is determined from the initial weight and from this total length the total length is based on the estimated number The length of an individual section resulting from the individual sections is calculated, the number of individual sections being changed if a predetermined length tolerance is exceeded. 2. Device for performing the method according to claim 1, characterized by the use of an electrical arithmetic unit, which in a first digit (33) by multiplication of the initial weight with the presettable reciprocal value of the weight per meter of the final cross-section the total length is calculated in a second digit (37) by dividing the total length defines the cutting length through the adjustable number of individual sections and the in a third point (40) the determined cutting length compares with preset extreme values, with an impulse for change from this point the number of individual sections is given as long as the determined cutting length is outside the set extreme values. 3. Apparatus according to claim 2, characterized in that a photocell (29) in the roller table is arranged behind the last finishing stand when passing the rod front end the calculated cutting length is passed on to the control of the cutting device by means of an impulse caused. 4. Apparatus according to claim 3 in conjunction with one behind the last finishing stand continuous line set up device for separating rolling stock, in particular rotating scissors, characterized by a fourth position (45) of the rake device obtained by dividing the specified cutting length by the measured exit speed of the rolled rod from the last The finishing stand defines the cutting sequence time and one of the cuts of the rotating shears (28) according to the cutting sequence time influencing pulse generator (48) for the first Cut at the moment of signaling by the photocell (29) for an adjustable time as compensation the path of the front end of the rod from the photocell (29) to the scissors (28) of the cutting sequence time added and this added value via a feedback from the scissors (28) by a pulse after completion of the first Cut again until after the delayed loss of the photo current Passing the rear end of the rod the impulse generation is interrupted. 1 sheet of drawings © 309 510/137 2.