US2258242A - Apparatus for drawing tubes of multiple wall thickness - Google Patents

Description

APPARATUS FOR DRAWING TUBES OF MULTIPLE WALL T HICKNESS Filed Sept. 27, 1940 W were? PEIZ-WSEA/ 2 Sheets-Sheet l Oct. 7, 1941. o. M. DITZEL ETAL ,2

APPARATUS FOR DRAWING TUBES ,OF MULTIPLE WALL THICKNESS Filed Sept. 27, 1940 2 Sheets-Sheet 2 4/ 4 I Z3 Z2 7 p IIIIIIIII VI/IIIIIIIIIIIIIIIIIII IIIIIII TMM rlllllllllllllgm -z Q INVENTORS 05cm MAROMEY 0/7254 *u wag? PFT'E'RJEIV Patented Oct. '7, 1941 A FPARATUS FOR DRAWING TUBES F MULTHLEWALL THICKNESS.

Oscar Maroney Ditzel, Rahway, and Victor Petersen, Plainfleld, N. J., assignors to Phelps Dodge Copper Products Corporation, Dover,

Del., a corporation of Delaware Application September 27, 1940, Serial No. 358,692 1 Claim. (01.205-7) I This invention: relates to the drawing of tubes of multiple ;wall thickness where the thickened Wallis used as an armor or reinforcement either in places alongthe length of the tube between the ends thereoi'so that itmay be bent at those points without reducing the gage at the outside of the bend thinner than the gage of the straight part, or at one or both ends to withstand flanging or expanding or at several points in the length of the 'tube to withstand the wear occasioned by supporting members. Furthermore this reinforcement may be on the outside or inside diameter of the tube as circumstances may require.

Many years ago it was proposed to draw tubes over a mandrel having reduced diameters in places along its length intermediate its ends and then by withdrawing the mandrel from the tube, those portions of the tube drawn into the reduced portions of the mandrel being thicker than the rest of the tube would be forced outwardly thereby forming a tube of multiple wall thickness with uniform inside diameter. While that looked to be perfect on paper it was found that the friction between the tube and mandrel where the length was over five. feet was so great that it was impossible to draw the tube off the mandrel without spoiling the tube.

We therefore propose to draw long tubes over a comparatively short plug held on the end of the usual plug rod co-axial with a die and in fixed relations thereto with means to withdraw and/or advance the plug with respect to the die to regulate the wall thickness of the tube being drawn and automatically to control the operation of the plug in its fixed relation to the die so that multiple tubes of identical wall thickness can be made in commercial production.

With this method of drawing, using our improved apparatus, we can draw tubes of maximum commercial lengths as readily as short pieces and we canrdraw tubes of most any shape, some of which are shown in the drawings and designated as series A, B. C, D, E, and F.

The foregoing and other features of our in- Y vention will now be described in connection with the accompanying drawings forming part of this specification in which we have illustrated our apparatus in its preferred form after which we shall point out more particularly in the claim whose features which we believe of our own joint invention.

In the drawings:

Figure 1 is a side view of a draw bench on which our apparatus is assembled, said bench to be newand being provided with the usual reciprocating carriage and die block.

'of the class A and B.

Figure 2 is a sideview of a means for moving the plug rod drawn to a somewhat enlarged scale.

Figure 3 is a detail of our plug rod mounting at right angles to that shown in Figure 2.

Figure 4 is a top view of that part of our apparatus shown in Figure 2.

Figure 5 is a section through the die and plug showing their relative position in drawing tubes Ii provided with the usual carriage I2 propelled back and forth on rails i3, said carriage is adapted to grip the end of the tube It which is in position over the rod i5 and extending through the die block it. As the travel of the carriage is to the left, as illustrated in Figure 1, the tube is drawn through the die and receives its shape depending upon the operation of the rod l5 and the position and shape of the plug 22 as will now be described.

- Mounted in the die block i8 is a die 2| and on the end of the rod I5 is a plug 22 which is held in predetermined relations to the die.

. In Figure 5 the plug 22. is tapered with two diameters 23 and 24. The smaller diameter 23 is on the end of the plug away from the supporting plug rod l5; by moving this plug to and from the die, relatively thickened portions M of the tube can be formed. This tube may then be drawn to a shape corresponding to the F series, Figure 7, by simply drawing a standard plug through the tube and forcing the inwardly extending thickened portions of the wall 4! outwardly, or it may be produced in a single operation as shown in Figure 6 when the plug 22 has a double taper with three diameters 25, 26, 21. This method is the subject of our former application #291,288 allowed July 9, 1940.

In order to control the movement of these plugs and to hold them in fixed relation to the die, we provide a mounting SI for the end of the ing the relative position of the die attached to main frame at dd. This lever $2 is moved by means of air cylinder 55 pivoted at 65 to a mounting 57 and connected to source of air pressure operated by solenoid valves 68, con-' trolled by llmit'switches 69. These switches are operated by a shoeilfi carried on the carriage l2.

By adjusting the switches 69 on predetermined centers, the air cylinder 65 is made to rock the lever 62 which advances or withdraws the plug 22 to or from the the H thus maintainand plug during the time when the particular thickness of the desired tube is being formed and when the wall thickness is to be changed will automatically move the plug to its proper position and hold it in its new position forming the other wall thickness. Y

In Figure 7 we show some of the tubes with 7 reinforced or armored walls. Series A and B may be formed in a single drawing operation when a plug of substantially theshape shown bracketed to the right and marked-Wis used.

The series C and D may be formed in asingle operation when a plug or substantially the shape shown bracketed to the right and marked X is used. Series E may be formed in a single operation when a plug of substantially the shape ilius trated as Y is used. Series F may be formed in changes or variations may be made as may be.

convenient or desirable without departing from the salient features of our invention and we therefore intend the following claim to cover such modifications as naturally fall within the lines of invention. We claim: Apparatus for forming a tube with multiple wall thickness in combination, means for ing a tube through a die, a plug having a reduced central portion and tapering gradually to an enlarged end portion on each end of the plug mounted to be reciprocated'on the end of a plug rod,.means to reciprocate the rod and to hold the plug in fixed relations to the die, means operable bythemoveme'nt of the drawing means to control the means to reciprocate the rod.

f OSCAR MARONEY DI'I'ZEL.

VIC'I'OR PETERSEN.

draw- 7

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