US1946933A

US1946933A - Tube-making apparatus

Info

Publication number: US1946933A
Application number: US602145A
Authority: US
Inventors: August P Diescher
Original assignee: DIESCHER TUBE MILLS Inc
Current assignee: DIESCHER TUBE MILLS Inc
Priority date: 1932-03-31
Filing date: 1932-03-31
Publication date: 1934-02-13
Anticipated expiration: 1951-02-13

Description

Feb. 13, 1934. A. P. DIESCHER,

TUBE MAKING APPARATUS Filed March 51, 1932 9 Sheets-Sheet 1 Feb. 13, 1934.

A. P. DIESCHER 1,946,933

TUBE MAKING APPARATUS Filed- March 31, 1932 9 Sheets-Sheet 2 Feb. 13, 1934.

A. P. DIESCHER 1,946,933

TUBE MAKING APPARATUS Filed' March 51. 1932' 9 Sheets-Sheet 3 9 Sheets-Sheet 4 Feb. 13, 1934. A. P. DIESCHER TUBE MAKING APPARATUS Filed March :51. 1932 FIG. 5

FIG. '7

FIG. E

Feb. 13, 1934. DIESCHER 1,946,933

TUBE MAKING APPARATUS Filed March 31, 1932 9 Shegs-Sheet 5 Feb. 13, 1934. DESCHER 1,946,933

TUBE MAKING APPARATUS Filed March 31. 1932 9 Sheets-Sheet 6 FIG. 14

/ F'll3.17

Feb. 13, 1934. p DlESCHER 1,946,933

TUBE MAKI NG APPARATUS Filed March 51. 1932 9 Sheets-Sheet 7 FIG. 15

L jfi j q w 9; FIG. 20 5:!

FIG. 22

Feb. 13, 1934. A. P. DIESCHER TUBE MAKING APPARATUS Filed March 31. 1932 9 Sheets-Sheet 8 5N vlllll/lllllll/l Feb. 13, 1934. A. P. DI ESCHER TUBE MAKING APPARATUS Filed March 31, 1932 l 9 Sheets-Sheet 9 Patented Feb. 13, 1934 UNITED. STATES PATENT OFFICE TUBE-MAKING APPARATUS Application March 31, 1932. Serial No. 602.145

25 Claims.

My invention relates to apparatus for making tubes by the. process of elongating a tubular blank upon a mandrel through the action of cross or equivalent helically acting rolls such as are ordinarily employed in billet piercing-in the manner, for example, which is disclosed in Letters Patent No. 1,870,209 issued to Samuel E. Diescher,

August 2, 1932. It is the main object of my invention to provide an apparatus for practicing the said process with especial economy and rapidity. Incidental objects of my invention, and

advantages secured thereby, will appear from the following specification.

One form of elongating apparatus embodying my invention is described, by way of example, in the following specification and shown in the accompanying drawings. It will be understood, however, that the invention may be embodied in other forms, and that changes may be made in the particular construction described and illustrated, without exceeding the scope of the invention, as defined in the appended claims.

In the drawings:

' Fig. 1 is a front view of the elongator proper,-consisting of a housing in which are supported the cross-rolls into the bite of which the billet, enclosing a suitable mandrel, is entered, the view being as seen from the line I-I of Fig. 4a, looking in the direction of the arrows, but on an enlarged scale.

Fig. 2 is a cross-section taken on the line IL-II of Fig. 1;

Fig. 3 is a section, taken as on the line IlI-III of Fig. 2 and upon a still further enlarged scale, illustrating the action of the cross-rolls and guide discs, an exaggerated clearance between the tube and mandrel being shown for purposes of clearness;

Figs. 4 and 4a, on sheets 2 and 3, together form a plan of the apparatus;

Fig. 5 is an end view of the apparatus, as seen from the line VV of Fig. 4, showing the mandrel receiving table, the mandrel feed table, and the inclined skids connecting the two tables;

Fig. 6 is a side elevation showing a portion of the mandrel feed table, the means for forwarding the mandrels into the billet pusher, and the means for actuating the latter, the view being as seen from the line VI---VI of Fig. 4;

t Fig. 7 is a side elevation of the billet-receiving table carrying the troughs in which the billet is supported prior to being moved into the elongator, the view being taken as seen from the line VII-VII of Fig. 4a;

Fig. 8 is a section on the line VIII-VIII 01 Fig. 7;

Fig. 9 is a detail front view showing the shape of a removable stop which is interposed between the billet-receiving table and the elongator;

Fig. 10 is a side elevation of the delivery-roller table on which the tube emerges from the elongator, the view being taken as seen from the line XX of Fig. 4a;

Fig. 11 (Sheet 3) is an end view of the gear- 5 housing employed in driving the. elongator, the view being taken as seen from the line Xl-XI 01 Fig. 4a;

Fig. 12 is a view of the tube-receiving roller table upon which the finished tube finally arrives. 7 showing the automatic means by which such tubes are transferred from the table, the view being taken as seen from the line XII-XE of Fig. 4a;

Fig. 13 is an enlarged cross section taken on 7 the line EHII-XIII of Fig. 12, showing one of the star wheels employed for transferring the finished tubes from the receiving table onto skids for delivering them to the mandrel-extraction table; 80

Fig. 14 is an end elevation of the apparatus as seen from the line XIV-IHV of Fig. 4a; and showing the tube-receiving table, the mandrelextraction table and the said skids;

Fig. 15 is a side elevation showing adjoining portions of the mandrel-extraction table and mandrel return table, the view being taken as seen from the line XV--XV of Fig. 4a;

Fig. 16 is a front view of the tube stop employed in connection with the extraction of the tube from the mandrel, as seen from the line XVI-XVI of Fig. 15;

Fig. 17 isa sectional plan taken on the line XVII-XVII of Fig. 16;

Fig. 18 is a side elevation showing the mandrel receiving table and the means by which the mandrels are transferred to the skids ready for re-delivery upon the mandrel-feed table, the view being taken as seen from the line XVI]IXVIII of Fig. 4;

Fig. 19 is a diagram showing circuit arrangements which may be employed in connection with the starting and stopping of the mandrel-feed apparatus and the billet-pusher actuating appa ratus;

Fig. 20 is a diagram illustrating circuit arrangements which may be employed for stopping the apparatus in case of a tube tending to arrive upon the receiving table before the tube previously produced has been transferred away therefrom; 110

Fig. 21 is a diagram showing circuit arrangements which may be employed in connection with the actuation of the apparatus for transferring the tubes away from the receiving table;

Fig. 22 is a diagram showing an electric circuit which may be employed for governing the operation of the mandrel-extracting rolls;

Figs. 23, 24 and 25 are schematic views showing successive positions of the parts in the production of a tube;

Figs. 26, 27 and 28 are schematic views showing successive positions of the parts in the extraction of a mandrel from the finished tube and the return of the mandrel to the mandrelreceiving table prior to being racked ready for use again; and

Fig. 29 is a plan showing an alternative construction of the means for feeding the mandrel into the pierced billet prior to elongating the latter to produce the tube.

The elongating apparatus proper does not, in and of itself, constitute a part of my present invention, but a suitable form of such apparatus is shown generally in Figs. 1 to 3 for purposes of clearness. It consists of a housing 10 carrying a centrally disposed feed guide 11 through which a tubular blank, containing a mandrel, is fed to rotating cross rolls 12 mounted in the housing 10. Grooved guide discs 13 are also mounted to rotate in the housing 10 and operate to control the flow of the metal of the billet while it is being kneaded by the cross rolls thereby to be elongated to produce the finished tube. The disposition of the cross rolls and guide rolls will be readily understood from Fig. 3 wherein the billet, with mandrel in place therein, is shown as being operated upon. From this figure, it will be seen that as disclosed in the above-mentioned Diescher Patent No. 1,870,209, the spacing of the discs 13 is such as to permit bulging of the blank away from the mandrel in the regions of the engagement of the blank by the discs, whereby when the elongation has taken place the internal diameter of the tube is greater than the diameter of the mandrel, so that the mandrel is loose in the tube and can be extracted readily therefrom.

According to my invention 1 provide means whereby a tubular blank is fed to a receiving support where it has introduced into it a mandrel, and whence it, with its enclosed mandrel, is fed into the elongator. After the finished tube emerges from the elongator it is transferred to a support where the mandrel is extracted therefrom, the mandrel being returned to the starting point, ready for introduction into a succeeding blank. The apparatus herein shown is described as employed for producing tubes from heated pierced billets; but apparatus according to my invention is also applicable to the production of tubes from tubular blanks made otherwise than by piercing, and in the cold state as well as the hot.

Referring particularly to Figs. 4, 5 and 6, the mandrels b, which circulate in the apparatus, are racked upon a table consisting of a plurality of skids 14 and 15, arriving thereon from a mandrelrecelving table on which they are delivered after use. The skids are suiiiciently inclined so that the mandrels will roll down them and be brought to rest in contact with one another, the first mandrel being stopped because of its engagement with a suitable abutment 16 which can be manually released by the operator in any desired manner. When the abutment is released the first mandrel rolls down upon the mandrel feed table, the remaining mandrels being stopped and remaining in place upon the skids. When the mandrels come from use they may be hot, and it will be observed that the number of mandrels that are on the skids 14 will determine the amount of time in which they have an opportunity to cool.

The mandrel feed table, 17a (Figs. *1 and 6), comprises a plurality of feed rollers 17 to which power is sometimes applied, as will hereinafter appear. Situated at the front end thereof is a set of mandrel pinch rolls 18o mounted in a housing 18, these pinch rolls being driven, through suitable reduction gearing, by a motor 19 (Figs. 4 and 6). The mandrel feed rollers are driven from the pinch rolls, as by means of a chain connection 20, in such manner that the feed rollers rotate somewhat more rapidly than the pinch rolls, with the result that the front end of a mandrel deposited on the feed rollers will catch up with the rear end of a mandrel that may be being forwarded by the pinch rolls. Thus if the mandrels are fed successively to the feed rollers, they will catch up with each other and maintain an end-to-end contact.

In front of the mandrel pinch rolls is a feed= pusher table 21 which supports a plurality of freely revoluble grooved rollers 22 (Figs. 4 and 6). Upon these rollers is supported a tubular pusher 23 in axial alignment with the mandrels, as forwarded by the mandrel pinch rolls, so that the mandrels when thus forwarded will be introduced into the pusher. Towards the front end of the pusher table is a pair of pusher-feed pinch rolls 24a mounted in a housing 24, the rolls being driven by a motor 25 (Figs. 4 and 4a).

In front of the feed-pusher pinch rolls is disposed a bil1et-receiving stand 26 (Figs. 4a, 7 and 8) in which is supported a pair of troughs 27 to which the billets are delivered. The billets are delivered to the troughs 27 over inclined skids 28 upon which, if heated, they may be placed after emergence from a suitable furnace, indicated at 29, a device 29a being employed for pushing the billets out of the furnace and onto a roller table 28a from which they are transferred to the skids 28.

Above the troughs 27 of the billet-receiving stand are disposed correspondingly shaped covers 30, these being mounted upon vertically reciprocating stems 31. The covers are adapted to be actuated, to cause. them to descend or rise, through the action of air cylinders 32 (Fig. 8) in which the stems 31 constitute pistons. When a billet is delivered to the troughs 27, the covers 30 are raised, butv thereafter, during the introduction of the billet into the elongator, the covers are lowered so as to enclose the billet between themselves and the troughs 27, thereby to confine the billet and prevent whipping of its trailing end while its leading end is being operated upon by the elongator.

Adjacent the front end of the billet-receiving stand 26 (Figs. 6 and '7) and at the rear end of the feed-pusher table 21,

flags

33 and 34, respectively, are provided. At the front end of the billet-receiving stand-which is opposite and adjacent to the receiving guide 11 of the elongator,-is provided a vertically reciprocable stop 35 (Figs. 7 and 9) adapted to be actuated by means of an air cylinder 36. The stop has a V- shaped notch 35a (Fig. 9) formed therein of such dimensions as to permit passage of a mandrel, but obstruct passage of a billet. Thus when the stop is raised, it prevents accidental forward movement of the billet towards the elongator, which might otherwise occur because of the lonitudinal movement of the mandrel therein. However when the stop is lowered the path of the billet to the elongator is unobstructed.

The operation of the apparatus, as thus far described, is as follows, reference being had, in particular to Figs. 23-25:

When a billet, designated a, is delivered to the troughs 27 of the billet-receiving stand, the parts will be in a position such as that indicated in Fig. 23. The stop 35 will be in its raised position; the billet pusher 23. will be in its retracted position; the mandrel forwarding pinch rolls 18a will be stationary, with a mandrel b partly forwarded and in the bite thereof; and a second mandrel will probably be on the mandrel feed rollers 17, with its front end in engagement with the rear end of the first mandrel. The operator then starts the mandrel. pinch rolls 18a, whereby the mandrel is moved forward through the tubular pusher 23 and into the billet a. If a second mandrel was not on the mandrel feed table at the time when the first mandrel was started forward, it would be delivered thereto just about that time, or immediately thereafter, and its front end would catch up with, and engage, the rear end of the first mandrel because of the fact that the mandrel feed rollers 17 rotate somewhat more rapidly than the mandrel pinch rolls 18a, as has been heretofore explained. When, therefore, the first mandrel emerges from the pinch rolls, the second mandrel will follow it into the pinch rolls, and the front end of the second mandrel will continue to press against the rear end of thefirst mandrel and move the latter forward.

The first mandrel is moved through the feed pusher and billet until its leading end strikes and actuates the flag 33. The actuation of the flag has the effect of stopping the mandrel-forwarding pinch rolls 18a, and therefore the mandrel feed rollers 17 which they drive. Thus-the second mandrel comes to rest in the position previously occupied by the first mandrel. The actuation of the flag 33 also actuates the air-cylinder 36 to cause the stop 35 to be depressed out'of the way of the billet, and, in addition, starts the feed-pusher forwarding rolls 24a, whereby the ,feed pusher 23 starts to move forward. The flag 34 is engaged by the rear end of the feed pusher, and is actuated by dropping off the latter upon the start of its forward movement. This actuation of the flag 34 operates the air cylinders 32 to cause the covers 30 to close downward upon the billet, the parts having then reached the position shown in Fig. 24.

As stated, the motor 25 which drives the feed pusher pinch rolls 24a is automatically started upon the actuation of the flag 33 by the leading end of the incoming mandrel. Such motor, however, is under the personal control of the operator, who can start, stop and reverse it at will. After the feed pusher 23 has moved forward a short distance, its front end engages the rear end of the billet a, whereby the latter is moved forward, carrying with it the mandrel b which it encloses. The billet is thus fed through the guide 11 of the elongator until its leading end enters the bite of the cross rolls 12 of the latter, between the guide discs 13. In accordance with well known principles, the driving motor for the cross-rolls, and its circuit arrangements, may be such that the cross-rolls rotate, when idle, at a low speed,

such as facilitates the picking up and the rotating of the billet, but accelerate, to an appropriately high elongating speed, when they are put under the load of elongating the billet.

The leading end of the mandrel passes freely through the cross rolls and is well in advance of the leading end of the billet. The metal of the billet, elongated to form the tube, will issue from the cross rolls at a higher speed than the mandrel, and by causing a material portion of the mandrel to lie, at first, in advance of the leading end of the billet a support is provided for a considerable time for the front end of the issuing tube, which, by reason of its speed of emergence from the cross rolls will catch up towards the leading end of the mandrel.

When once the leading end of the billet has entered the bite of the cross rolls, and elongation has commenced, the forward movement of the billet will result from the action of the cross rolls, the feed pusher being no longer required for moving the billet forward. However, were the trailing ends of the billet and mandrel free they would be liable to whip around in a wide path, and this might occur as soon as the trailing end of the billet passed beyond the troughs 27 and covers 30. Accordingly the operator, who, as stated, has the feed pusher pinch rolls 24a under his control, so manages these pinch rolls that the leading end of the feed pusher will follow closely the trailing end of the billet. Thus the feed pusher itself, confined between the troughs 27 and covers 30, will enclose the trailing end of the mandrel, and restrain any tendency of the latter, or of the billet, to whip, even after the trailing end of the billet has left the troughs 27. The position of the parts, with the feed pusher guiding the trailing end of the mandrel in the manner just described, when the leading end of the billet has entered the elongator, is shown in 115 Fig. 25.

When so much of the billet has been elongated that only a short length of the trailingend of the mandrel, not sufiicient for there to be any liability to whip harmfully, remains (see position 1 of the second, partly elongated, billet in Fig. 23), the operator reverses the motor 25 for actuating the feed-pusher pinch rolls and retracts the pusher to its original position shown in Fig. 23. In so returning, the feed pusher actuates the flag 34, by raising the latter, the effect of such actuation of the flag being that the air cylinders 32 are operated to raise the covers ready for the reception of a new billet by the troughs 27. This actuation of the flag 34 also has the eifect of stopping the motor 25 of the pusher pinch rolls, whereby the pusher is brought to rest in its retracted position. Upon the trailing end of the billet passing the flag 33, and the feed pusher 23 being retracted, the flag 33 falls, this actuation 135 of the flag causing the air cylinder 36 to be operated to raise the stop 35.

In the above manner the parts are brought back to their original position shown in Fig. 23, and the operation may thereupon be immediately 140 repeated, as is indicated in that figure by the billet a, the partly elongated billet, and the billet elongated into the form of a complete tube, all shown in position in the apparatus at the same time.

Various circuit arrangements, within the knowledge of those skilled in the art, are available for obtaining the above results as to starting and stopping by the flags, etc. One such cir cuit is shown in Fig. 19, in which 37 and 38 indicate the power lines and 39 indicates a switch for starting, stopping and reversing the motor 19 which actuates the mandrel-feeding pinch rolls. When the switch 39 is moved to maize con= nection with its forward contact 40, current flows from the line 37 through the switch and contact d0 to one of a pair of contacts .31 of a switch 42 actuated by flag 33, and when such contacts 41 are connected, through the forward coil 43 of a switch id, back to the line 33. When the switch 4-4 is actuated, because of the forward coil 43 being energized, its contactors a5 and co establish such connections as cause the motor 13 for actuating the mandrel feed pinch rolls to be driven in a forward direction. The switch 42 carries a contactor 4'7 which bridges the contacts 41 when the flag 33 is not raised,--i.e., when it is in the position shown in Fig. 23,-and enables the motor 19 to be energized in a forward direction in the manner just noted. When the mandrel strikes the flag 33 the contactor 4-? is raised, and therefore the motor 19 is stopped.

The switch 42 has a second contactor, d3, adapted to bridge contacts 49 disposed in the circuit of an electro-magnet 50 for actuating an air valve 51 controlling the admission of air to the air cylinder 36 for operating the stop 35. When the fiag 33 is in the position shown in Fig. 23 the contactor 48 completes the circuit for the magnet 50, but when the flag 33 is operated by the mandrel this circuit is broken and the air cylinder 26 operated to cause the stop 35 to drop out of the path of the billet.

The switch 42 has a back contactor 52 which is normally out of contact with a pair of contacts 53, one of which is connected with the for-= ward contact 54 of a switch 55 for controlling the motor 25 which actuates the feed pusher pinch rolls, the other contact 53 being connected, through a line 53a with the forward coil 56 of a switch 57. When the switch 55 is in its forward position, engaging the contact 54, current will flow from the line 37 to the switch 55 and through the contact 54 to one of the contacts 53 of the switch 42. The circuit will here be broken when the fiag 33 is in the position shown in Fig. 23. However, when the flag is actuated by a mandrel, the back contactor 52 will be raised so as to connect the contacts 53 of the switch 42 and the circuit will be completed through the line 53a and coil 56 to the line 38. The switch 57 will thus be actuated to cause the motor 25 to operate in a forward direction, causing the feed pusher to start forward as above described.

A second switch, 58, is provided in the circuit, and is operated by the flag 34. This switch has a pair of contacts 59 which are bridged by a contactor 60 when the feed pusher is in its retracted position and the flag 3 in the posi tion shown in Fig. 23. The contacts 59 are in the circuit of an electro-magnet 61 connected between the

lines

37 and 33, which magnet operates a valve 62 for the air cylinders 32 which operate the covers 30. When the flag at is actu-= ated by dropping off the end of the feed pusher, when the latter begins to move forward, the contactor 60 breaks connection between the contacts 59 and the valve 62 is thereby operated to cause the air cylinders 32 to allow the covers 30 to descend, in the manner above described.

It will be seen that the forward rotation of the feed pusher pinch rolls is dependent upon the back contactor 52 of the switch 42 being closed by reason of the flag 33 having been raised reac es by the entry or presence of the mandrel, billet or feed pusher. When the pusher is to be re-= tracted, the operator moves the switch 55 in the reverse direction, to make connection with a reverse contact 63 which is connected with one of a pair of separated contacts ca, the other contact of such pair being connected with a reverse coil 65 of the switch 57. Thus the motor 25 can only be reversed, to retract the pusher, when the contacts 64 are connected with. each other. Such connection of the contacts 64: is established, by a back contactor 66 with which the switch 58 is provided, whenever the flag 34 has fallen into the position shown in Fig. 24 or 25 by reason of the pusher having moved forward.

The tube emerges from the elongator upon a delivery roller-table 66a (Figs. 4a and 10), the rollers 67 of which are driven by a motor 63, and passes from such delivery table through a tubular guide 69 to a receiving table.

The tubular guide (Figs. lO'and 11) is carried by the housing '10 of gearing through which power is transmitted to the-cross-rolls 12 of the elongator. In apparatus requiring so much power as do the cross-rolls 12, it is desirable to avoid bevel gears or other devices for transmitting power from one shaft to another disposed angularly with respect thereto, as far as is feasible. To this end, the motor, 71, which drives the cross-rolls, is placed to one side of the tube-delivery and tube-receiving tables, and its shaft 72 is made to drive, through appropriate gearing, a pair of shafts 73, one of which is on each side of the line along which the tube emerges from the elongator. the gears which drive them, are so arranged as to leave space for the tubular guide 69. These shafts are connected with universal shafts i4 which drive the cross-rolls.

The tube passes from the delivery table and through the guide 69 onto the receiving rollertable 75 (Figs. la and 12) the rollers 76 of which are driven by a motor 77. The rollers 76 of the receiving table are preferably operated at a somewhat higher circumferential speed than the rollers 67 of the delivery table, so that the speed of movement of a tube will be increased when it arrives upon the receiving table, its trailing end being thereby rapidly moved out of the way of the tube next following. A stop 78 is provided at the end of the receiving table to prevent undue forward movement of the tubes before they are transferred away from the receiving table in the manner shortly to be described.

A flag '73, situated in the path of the tube, is mounted upon the gear housing 70 just beyond the tubular guide 69, and a second such flag, 80, is mounted on the receiving table. These flags make connections by virtue of which the. elongator will be stopped if a tube is on the receiving table l5, causing depression of the flag 80, at the same time as a succeeding tube emerges on the delivery table to such an extent as to actuate the flag 79. This avoids the possibility of a wreck due to the forward end of an issuing tube colliding with the trailing end of the tube just' produced.

One of a number of suitable circuit arrangements for producing the result just described is shown in Fig. 20. In this figure is shown a switch 31 disposed in the circuit of the motor '71 for driving the elongator, the contactor 82 of such switch being normally closed, permitting operation of the motor, but being adapted to be The shafts '73, and

lid

opened, to stop the motor, by an electro-magnet 83. The electro-magnet is connected. in circuit with contacts 84 which are normally disconnected but are adapted to be connected by a contactor 85 operated by the flag 80, and with contacts 86 which are likewise normally disconnected but adapted to be connected by a contactor 87 operated by the flag '79. It will be observed that in the normal proper operation of the apparatus one or the other of the flags 79 and will always be raised (as in Figures 23-25), and in those circumstances no current can flow through the electro-magnet 83, so that the motor 71 for the cross rolls will continue to run. Should, however, a tube issue past the flag 79 before the preceding tube had been removed from the receiving table 75, the

flags

79 and 80 would be depressed at the same time, and in these circumstances the electro-magnet 83 would be energized, the switch 81 opened, and the motor 71 stopped.

The finished tube, containing the mandrel, is transferred from the receiving table '75 to

skids

88, 88a down which it rolls to the mandrel extraction table. This transfer is effected by means of star wheels 89 (Figs. 4a, 12 and 13) mounted upon a shaft 90, which is revolved through onethird of a revolution upon the actuation of a flag 91 located in the path of the leading end of the finished tube. The star Wheel has three arms so shaped that an arm, during one-third of ,a revolution of the star wheel, will raise a tube from the rollers '76 of the receiving table and deposit it upon the skids 88.

The operation of the star wheel shaft 90, to cause it to turn through one-third revolution upon the actuation of the flag 91, can be effected in numerous manners that will be readily understood by those skilled in the art. One suitable arrangement of mechanism and circuit is diagrammatically illustrated in Fig. 21. In this fig ure, 2: motor 92 is shown as driving a shaft 93 which in turn drives, by a gearing 94 of a oneto-three ratio, the shaft 90 of the star wheels 89. In the circuit of the motor 92 are a pair of contacts 95 adapted to be bridged by the back contactor 96 of a switch 97 adapted to be actuated upon energization of a coil 98. Such coil is in circuit with contacts 99 adapted to be bridged by a contactor 100 actuated by the fiag 91. Thus when the flag 91 is operated, circuit is established through the coil 98 and the switch 97 is closed to energize the motor 92.

Some suitable means is provided for .stopping the motor 92 after the shaft 93 has made one revolution and therefore the star wheels 89 onethird of a revolution. As shown, this means consists of a disc 101 mounted on the shaft 93 and having therein a notch 102 into which can drop a roller 103 upon one arm of a pivoted lever 104. The other arm of the lever carries a contactor 105 adapted to bridge contacts 106. These contacts are in circuit with the coil 98 and with a pair of contacts 107 adapted to be bridged by a second back contactor, 108, of the switch 97. When the flag 91 is operated, the switch 97 will be closed and the motor 92 will start to rotate. On the shaft 93 starting to turn, the roller 103 will be raised out of the notch 102 and will be sustained by the edge of the disc 101. Thus, although the flag 91 will resume its original position shortly after the shaft 93 begins to rotate-because of the lifting of the tube from the receiving tabla-the switch 9'7 will remain closed because of the holding circuit established through the line which includes the

contacts

106 and 107. When, however, the shaft 93 completes its revolution the roller 103 will drop back into the notch 102 and the holding circuit will be broken, causing the switch 97 to open and the motor 92 to stop, suitable braking means being employed to the latter end.

The tube, after being removed from the receiving table 75, in the manner above described, rolls down the skids 88 and is received upon the rollers 109 of the mandrel extraction table 110 Figs. 4a, 14 and 15). The rollers 109 are driven by a motor 111 and cause the tube, and the mandrel contained therein, to move lengthwise towards the mandrel-extracting pinch rolls 112, which are supported in a stand 113 and driven by a motor 114.

The mandrels are of such length that when the tube is completed, the trailing end of the mandrel will project beyond the trailing end of the tube, as shown in Fig. 12. When, therefore, the tube and mandrel are moved lengthwise by the rollers 109 of the mandrel extraction table, the end of the mandrel will enter between the extracting pinch rolls 112. The bearing for the upper of these rolls is carried by a screw 140 adapted to be rotated, through a rack and pinion, by the piston 141 of an air cylinder. A valve-operating arm 142 is placed just beyond the pinch rolls, so as to be engaged and actuated when a mandrel enters between the rolls (Fig. 15). The actuation of this arm causes air to be applied to the cylinder and the screw 140 to be rotated so as to move the upper pinch roll 112 downward into driving engagement with the mandrel. In this manner provision is made for an easy entry of the mandrel into the extracting pinch rolls and a subsequent definite for warding movement of the mandrel, to extract it from the tube. The motor 114 for driving the extracting pinch rolls is of such character that it will speed up upon load being applied thereto; so that upon the end of the mandrel entering the rolls and being seized thereby, the mandrel being, as has been stated, loose in the tube, will be rapidly extracted lengthwise from the tube.

A stop 143 (Figs. 1517) is removably mounted in a stand 144 placed between the table and pinch rolls 112, and has therein a hole 145 of a size which will permit passage of the mandrel but not of the tube.

The motor 114 for the extracting pinch rolls is inter-connected with the motor 111 for driving the rollers of the extraction table 110 in such a manner that when load is imparted to the motor 114 the motor 111 will stop. Suitable connections for this purpose are shown in Fig. 22, from which it will be seen that a switch 116, adapted to be opened upon the energization of a coil 117 disposed in series with the armature of the motor 114, is interposed in the armature circuit of the motor 111. Thus when current in the armature circuit of the motor 114 increases,- which will be the case when load is applied because of a mandrel being seized by the pinch' from the tube, its leading end will strike and actuate a flag 120 which energizes a motor 121 so as to operate the shaft 122 of transfer star wheels 123, in the same manner that has already beendescribed in connection with the operation of the star wheel shaft 90. The star wheels 123 lift the tube, from which the mandrel has been extracted, from the rollers 109 of the extracting table, and deposit it upon skids 124 down which it -can roll to any desired cooling or storing means.

Were the flag 120 held down, by reason of a mandrel passing thereover, long enough, the star-wheel shaft 122 might start a second onethird revolution, and a following mandrel might have entered the stop 143 or the extracting pinch rolls 112, in which case a wreck would occur. To obviate any possibility of this, a second flag, 115 (Figs. 2628), is placed between the extracting rolls 112 and the flag 120, the switch it operates being placed in series with the switch operated by the flag 120. Thus the motor 121 cannot be energized unless both flags are depressed, and by suitably proportioning the distance between the flags to the length of the mandrel all danger of the above character is avoided.

The mandrels are delivered by the rollers 118 onto the rollers 125 of the mandrel-receiving table 126, at the end of which a stop 127 is provided to prevent movement of the mandrels beyond the proper point for their delivery to the skids 14 (Figs. 18 and 5) on which they are stored ready for use again. Adjacent the end of the mandrel-receiving table-126 is a flag 128 which controls the actuation of a motor 129 adapted to turn, through one-third of a revolution, the shaft 130 of star wheels 131.

As has been stated, the apparatus of my invention may be embodied in numerous other structural forms than that described and shown, without exceeding the scope of the invention as defined in the claims hereto annexed. As one illustration of this, there is shown in Fig. 29 a modification of the apparatus for feeding the billet and mandrel into the elongator, in which the mandrel is not fed through the feed-pusher as is the case in the construction describ d above.

In the form of feeding apparatus shown in Fig. 29 the mandrel feed table, 17a, may be the same as before, but it is placed beyond the line in which the billet is fed into the elongator and delivers the mandrels to a forwarding table 132 carrying live roller 133 by means of which the mandrel is fed forward into a billet supported in troughs 134. The billet may go to the troughs 134 along skids 135 in the same manner that the billets go to the troughs 27 along the skids 28 in the construction heretofore described. A stop 136, which prevents longitudinal movement of the billet but permits passage of the mandrel, and which may be of similar shape to the stop 35 described above, is placed beyond the troughs 134 to prevent undue longitudinal movement of the billet when the mandrel is fed thereinto. A stop 137 is placed beyond the stop 135 to arrest movement of the mandrel.

The mandrel is fed into a billet lying in the troughs 134 and comes to rest with its leading end against the stop 137. At this stage, the billet, containing the mandrel, is lifted out of the troughs 134 and deposited upon the skids 138, down which the billet and mandrel roll into receiving troughs in which they are supported ready for feeding forward into the elongator. The means for transferring the billet and mandrel from the troughs 134 to the skids 138 may consist of star wheels 139 similar to those described above. The receiving troughs may be the same as the troughs 27 heretofore described and, like them, are provided with covers 30. With the billet and mandrel in position in the receiving troughs, the billet may be fed forward into the elongator by a pusher such as the pusher 23 heretofore described.

Where the term cross rolls is employed in the appended claims I intend to include rolls, discs or the like which by their revolution against a work-piece enclosed between them impart a reducing and helical forwarding movement to the work-piece.

I claim:

1. Apparatus for elongating a tubular blank around a mandrel to produce a tube. comprising, in combination, cross-rolls, a support on the feeding side of said cross-rolls for receiving a blank and a mandrel contained therein, a guide cooperating with said support and movably associated therewith to permit lateral feeding of a blank'to said support, and a pusher adapted to engage the end of the blank and enter between said support and said guide, the engaging end of said pusher being provided with a recess for receiving the end of the mandrel, whereby said pusher is guided by said support and guide and guides the trailing end of said mandrel.

2. Apparatus for elongating a tubular blank around a mandrel to produce a tube, comprising, in combination, cross-rolls, a blank-support, a mandrel magazine, means for delivering the mandrels one at a time from said magazine, means for feeding the delivered mandrel into a blank on said support, and a pusher for feeding said blank and the mandrel contained therein to said cross-rolls.

3. Apparatus for elongating a tubular blank around a mandrel to produce a tube, comprising, in combination, cross-rolls, a blank-support, a mandrel magazine, means for feeding a mandrel from said magazine to enter a blank upon said support, guiding means for said blank, and a 1 0 pusher for feeding said blank and the mandrel contained therein to said cross-rolls, said pusher entering said guiding means and being guided thereby.

4. Apparatus for elongating a tubular blank 125 around a mandrel to produce a tube, comprising, in combination, cross-rolls, a blank-support, a mandrel magazine, means for feeding a mandrel from said magazine to enter a blank upon said support, a pusher for feeding said blank and the mandrel contained therein to said cross-rolls, said pusher having therein a recess for receiving and guiding the end of the mandrel, and means for guiding said pusher while operating as a guide for the mandrel. 4 135 5. Apparatus for elongating a tubular blank around a mandrel to produce a tube, comprising, in combination cross-rolls, a blank-receiving trough, a cover movably associated with said trough to permit feeding of a blank. laterally thereto, a mandrel magazine, means for feeding a mandrel from said magazine into a blank, and a pusher for feeding said blank and mandrel to said cross-rolls.

6. Apparatus for elongating a tubular blank around a mandrel to produce a tube, comprising, in combination, cross-rolls, a blank-receiving trough, a cover movably associated with said trough to permit feeding of a blank laterally thereto, a mandrel magazine, means for feeding 150 a mandrel from said magazine into a blank, and a pusher for feeding said blank and mandrel to said cross-rolls, whereby said blank and mandrel pass through the cross-rolls and the blank is elongated around the mandrel to produce a tube, means for disassociating the mandrel and tube, and means for returning the mandrel to said magazine.

'7. Apparatus for elongating a tubular blank around a mandrel to produce a tube, comprising, in combination, cross-rolls, a blank-support, a blank-guide associated with said support and movable into and out of cooperative relation therewith, means for feeding to said cross-rolls a blank and a mandrel contained therein, and means, controlled from said feeding means, for moving said guide into cooperative relation with said support.

'8. Apparatus for elongating a tubular blank around a mandrel to produce a tube, comprising, in combination, cross-rolls, a blank-support, a blank-guide associated with said support and movable into and out of cooperative relation therewith, a pusher adapted to enter between said support and guide for feeding a blank and mandrel from said support to said cross-rolls, means for actuating said pusher, and means, controlled from said actuating means, for moving said guide into cooperative relation with said support.

9. Apparatus for elongating a tubular blank around a mandrel to produce a tube, comprising, in combination, cross-rolls, a blank-support, rollers disposed in alignment with the axis of a blank carried by said support for feeding a mandrel through such blank, means for stopping the feeding of the mandrel when the leading end thereof protrudes beyond the leading end of the blank, and means for feeding to said cross-rolls the blank and the mandrel contained therein.

10. Apparatus for elongating a tubular blank around a mandrel to produce a tube, comprising, in combination, cross-rolls, a mandrel magazine, a blank-support, rollers disposed substantially 'in alignment with the axis of a blank carried by said support for feeding a mandrel from said magazine into such blank, means for feeding the blank and mandrel into said cross-rolls, whereby said blank and mandrel pass through the cross-rolls and the blank is elongated around the mandrel to produce a tube, means for disassociating the mandrel and tube, and means for returning the mandrel to said magazine.

11. Apparatus for elongating a tubular blank around a mandrel to produce a tube, comprising, in combination, cross-rolls, means for introducing a mandrel into a blank so that the trailing end of the mandrel protrudes beyond the trailing end of the blank, means for feeding the blank and mandrel to said cross-rolls, whereby said blank and mandrel pass through the cross-rolls and the blank is elongated around the mandrel to produce a tube, means operating upon the trailing end of the mandrel for extracting the latter from the tube, and means for returning the mandrel to said introducing means.

12. Apparatus for elongating a tubular blank around a mandrel to produce a tube, comprising, in combination, cross-rolls, means for introducing a mandrel into a blank so that the trailing end of the mandrel protrudes, beyond the trailing end of the blank, means for feeding the blank and mandrel to said cross-rolls, whereby said blank and mandrel pass through the cross-rolls and the blank is elongated around the mandrel to produce a tube, pinch rolls for operating upon the trailing end of the mandrel for extracting the latter from the tube, and means for returning the mandrel to said introducing means.

13. Apparatus for elongating a tubular blank around a mandrel to produce a tube, comprising, in combination, cross-rolls, means for introducing a mandrel into a blank so that the trailing end of the mandrel protrudes beyond the trailing end of the blank, means for feeding the blank and mandrel to said cross-rolls, whereby said blank and mandrel pass through the crossrolls and the blank is elongated around the mandrel to produce a tube, a support for receiving the tube and mandrel, a second support disposed out of line with said first-named support, means for transferring the tube and mandrel from said first to said second-named support, means at said second-named support operating upon the trailing end of the mandrel for extracting the latter from the tube, and means for returning the mandrel to said introducing means.

14. Apparatus for elongating a tubular blank around a mandrel to produce a tube, comprising, in combination, cross-rolls, means for introducing a mandrel into a blank so that the trailing end of the mandrel protrudes beyond the trailing end of the blank, means for feeding the blank and mandrel to said cross-rolls, whereby said blank and mandrel pass through the cross-rolls and the blank is elongated around the mandrel to produce a tube, a support for receiving the tube and mandrel, pinch rolls for operating upon the trailing end of the mandrel to extract the latter from the tube, means, disposed out of line with said support, for moving the tube and mandrel towards said pinch rolls, means for transferring the tube and mandrel from said support to said last-named means, and means for returning the mandrel to said introducing means.

15. Apparatus for elongating a tubular blank around a mandrel to produce a tube, comprising, in combination, cross-rolls, means for feeding to said cross-rolls a blank and mandrel contained therein, delivery rollers for receiving the tube and mandrel from said cross-rolls, receiving rollers for said tube and mandrel, and means for driving said delivery and receiving rollers, the

peripheral speed of said receiving rollers being higher than that of said delivery rollers.

16. Apparatus for elongating a tubular blank around a mandrel to produce a tube, comprising, in combination, cross-rolls, means for feeding to said cross-rolls a blank and mandrel contained therein, a support for receiving the tube and L mandrel, means for extracting the mandrel from the tube when on said support, means for removing the tube from said support after extraction of the mandrel, and means actuated by the extracted mandrel for causing said last-named means to operate.

17. Apparatus for elongating a tubular blank around a mandrel to produce a tube, comprising, in combination, cross-rolls, a magazine for receiving mandrels side by side, a blank-support, rollers for feeding a mandrel delivered from one side of said magazine to a blank on said support, means for feeding the blank and mandrel to said cross-rolls, thereby to produce a tube containing the mandrel, a support for the tube and mandrel, rollers for returning the mandrel from said support to said magazine at the other side thereof, means for extracting the mandrel from the tube on said support and delivering it to said returning rollers, and means actuated by the mandrel for causing the tube to be removed from said support after extraction of the mandrel.

18. Apparatus for elongating a tubular blank around a mandrel to produce a tube, comprising, in combination, cross-rolls, means for introducing a mandrel into a blank, means for feeding the blank and mandrel to said cross-rolls, whereby said blank and mandrel pass through the crossrolls and the blank is elongated around the mandrel to produce a tube, means for enclosing and guiding the trailing end of the blank during operation thereon by said cross-rolls to prevent whipping of said trailing end, means for disassociating the mandrel and tube, and means for returning the mandrel to said introducing means. 19. Apparatus for elongating a tubular blank around a mandrel to produce a tube, comprising, in combination, cross-rolls, means for introducing a mandrel into a blank, means for feeding the blank and mandrel to said cross-rolls, where by said blank and mandrel pass through the crossrolls and the blank is elongated around the mandrel to produce a tube, means for enclosing and guiding the trailing end of the mandrel during operation on the blank by said cross-rolls to prevent whipping of said trailingend, means for disassociating the mandrel and tube, and means for returning the mandrel to said introducing means.

20. Apparatus for elongating a tubular blank around a mandrel to produce a tube, comprising, in combination, cross-rolls, means for introducing a mandrel into a blank, means for feeding the blank and mandrel to said cross-rolls, whereby said blank and mandrel pass through the crossrolls and the blank is elongated around the mandrel to produce a tube, means for maintaining the trailing ends of the blank and mandrel in substantial alignment with the pass between said cross-rolls during operation of the latter upon said blank to prevent whipping of said trailing ends, means for disassociating the mandrel and tube, and means for returning the mandrel to said introducing means.

21. Apparatus for elongating a tubular blank around a mandrel to produce a tube, comprising, in combination, cross-rolls, means for introducing a mandrel into a blank, means for feeding the blank and mandrel to said cross-rolls, whereby said blank and mandrel pass through the crossrolls and the blank is elongated around the mandrel to produce a tube, a delivery table for receiving the tube and mandrel from said crossrolls, receiving rollers disposed beyond said delivery table, means for driving said receiving rollers at a peripheral speed in excess of the speed of delivery of the tube by said cross-rolls, means for disassociating the mandrel and tube, and means for returning the mandrel to said introducing means.

22. Apparatus for elongating tubular blanks around mandrels to produce tubes, comprising, in

combination, cross-rolls, means for feeding 1n succession to said cross-rolls blanks and mandrels contained therein, a delivery table for receiving the tubes and mandrels from said cross-rolls, receiving rollers for the tubes and mandrels disposed beyond said delivery table, means for driving said receiving rollers at a peripheral speed in excess of the speed of delivery of the tube by said cross-rolls, and automatic means for interrupting the operation of said cross-rolls upon a tube approaching said receiving rollers when another tube is present thereon. 23.'Appara tus for elongating tubular blanks around mandrels to produce tubes, comprising, in combination, cross-rolls, means for feeding in succession to said cross-rolls blanks and mandrels contained therein, delivery rollers for receiving the tubes and mandrels from said cross-rolls, receiving rollers for said tubes and mandrels, means for driving said delivery and receiving rollers, the peripheral speed of said receiving rollers being higher than that of said delivery rollers, means for discharging the tubes and mandrels from said receiving rollers, and means for preventing the delivery of one tube and mandrel to said receiving rollers before the preceding tube and mandrel have been discharged therefrom.

24. Apparatus for elongating a tubular blank around a mandrel to produce a tube, comprising, in combination, a support for receiving a blank, means associated with said support for introducing a mandrel into a blank thereon, cross-rolls, a support at the entry side of saidcross-rolls,means for transferring a blank and contained mandrel from said first to said second-named support, means for feeding the transferred blank and mandrel from said-second-named support to said cross-rolls, whereby said blank and mandrel pass through the cross-rolls and the blank is elongated around the mandrel to produce a tube, means for disassociating the mandrel and tube, and means for returning the mandrel to said introducing means.

25. Apparatus for elongating a tubular blank around a mandrel to produce a tube, comprising, in combination, cross-rolls, a support at the entry side of said cross-rolls, a support for-receiving a blank, said support being disposed laterally of said first-named support, mandrel-receiving means, means for feeding a mandrel from said receiving means into a blank on said secondnamed support, means for transferring a blank and contained mandrel laterally from said second and the blank is elongated around the mandrel to produce a tube, means for disassociating the mandrel and tube, and meansfor returning the mandrel to said mandrel-receiving means.

AUGUST P. DIESCHER.