FI125605B - Method and apparatus for tube cutting - Google Patents

Description

Method and device for the shape of the pipe end section

The invention relates to a method for the pipe end to form a section, wherein the end of the pipe is cut two curved edge for return through dro-Tinter and the mold, for which the punch blade has a curved cutting edge and the mold is responsible for the cutting arc shape of arc, and the pieces of cuts is made from inside the tube end out in two successive cutting stage.

The invention also relates to a device for the shape of the pipe end section, which device comprises a bayonet blade having a corresponding curvature of the piece to be cut the cutting edge, and the deformable mold support tube, wherein the mold has a corresponding arc shape of arc of the cutting edge.

In the manufacture of relatively thin-walled flow tubes T connection shaft and the branch pipes are joined by welding. Round shape of the tube requires the formulation components incorporated to allow welding.

The best-known way is to make the welding from the outside of the pipe on the outer surface. Especially in order to ensure the welding of relatively thick tubes of the branch pipe end of the oblique cut so that the branch pipe end to the body of the arc tube surface, the point of impact formed by outwardly opening V-groove (bevel). Such leikkaussuorite is set forth in GB 1,025,685.

Welding methods, which accompany the pipes are welded without filler metal, to accompany the melting parts of the inside of the pipe, accompanied by the required parts of a different preparation. The colliding frame tube of the branch pipe end face (cut end) must join the entire surface without gaps (closely) frame tube to the outer surface. The branch pipe of the curved portion of the shear zone may not be leikkauspurseita corner of the inner tube. Cutting is thus carried out from the inside out.

US patent 4,986,154 is known of the above type method and apparatus in which the shape cutting is performed inside the pipe outwards. Between the pad surgery tube must be removed, rotated 180 °, in some places-va and paid. These measures are difficult to automate. In addition, the bayonet blade design vatii great use of force and possible branch-tube end face (cut end) coalescence of the entire surface without gaps (closely) frame tube to the outer surface, because the cutting edge span corresponds to the inside diameter of the pipe to be cut. In this case, leikkauskaarten the area between the end of the tube remains uncut surfaces, which are part of the original tube-end typintaa.

From the patent publication DE 1096717 is known the above type method and a device for cutting can be carried out from inside the pipe outwards at the same time the cutting blade in both directions. Also in this leikkauskaarten the area between the end of the tube remains uncut surfaces, which are part of the original pipe end surface. Moreover, in both functional directions of the cutting blade is difficult to design so that it is sufficiently durable.

The purpose of the invention is to provide a method and apparatus for cutting will be completed tube inside out so that the cutting arc span is substantially larger than the cut tube inner diameter, or may be greater than the cut tube outside diameter or, if desired substantially corresponds to the deformable tube to the outer diameter.

This object is achieved as disclosed in the appended claim 1 and a method as set forth in claim 3 device. The dependent claims disclose preferred embodiments of the invention.

In addition to the mechanical leikkaussuoritteen the shape of the cutting device must be able to handle a certain range of different sizes and different lengths of blanks and easily replaceable tool arrangements. In addition, the device operating working processes tries have be able to automate dealing with large volumes. By means of the invention, these objectives can also be achieved.

The invention is illustrated with reference to the accompanying drawings, in which

Figure 1 shows the shape of the cut end of the pipe sectional direction,

Figure 2 shows the shape of the cut end of the tube 90 ° from the Figure 1 and turned in addition muotoleikkauspistintä pistinterineen a side view, partly in section,

Figure 3 shows a die-cut tube and muotoleikkauspistintä top view of the set 7,

Figure 4 shows a muotoleikkauspistintä inserted in the head pipe ready for the first cutting step,

Figure 5 shows a pipe end inserted into the muotoleikkauspistintä ready in the second cutting step, and

Figure 6 shows a schematic sectional shape of a side view of the device, illustrating the movements and arrows to different parts of the turntable 6 7 for supporting and moving the molds.

If the tube is attached to one end of the same diameter or larger diameter of the second tube, one end of the tube is cut to shape so that the sectional line 2a is a sectional view taken in the direction of the half-circle or circular arc. Samanhalkaisijaisilla pipes 2a-sectional radius of the arc is the same as the outer radius of the tube 1. If the pipe 1 is connected to branch pipes larger diameter main pipe, it is cutting all 2a, respectively, made the frame tube ul-kosädettä a similar arc. Cutting the tendon of the arc 2a is substantially the same as the deformable outer diameter of the tube 1, wherein leikkauskaarien 2a junctions formed by sharp edges 2.1, bounded by the outer surface of the tube.

The tube 1 central axis C parallel to the shaft 5 is attached to the end of the punch blade 3, 4, which has a sharp edge, the arc-shaped cutting edge 4. The cutter arc of radius equal to the outer radius of the tube. This is achieved e.g. by making an otherwise flat surface and a curved surface to a blunt protrusion with the plane of the surface and the cutting line arched surface forms a cutting edge 4.

The device has two two-part mold 7, with the corresponding diameter of the pipe to be cut puoliura mold parting plane. The mold 7-päätyreu the second direction is perpendicular to the view of the division level to be cut corresponding to the shape of the arc curves concentrically relative to the division plane into the groove, wherein the split level muotokaarien and sharp corners formed by the meeting point, and interest rates on both sides. Mould opening of the lower groove acts cut the pipe reception room. The upper mold half is lowered onto the tube and the cutting position of the mold halves are pressed immovably against each other.

Surgery is performed in two consecutive steps. Both cutting steps are performed at the same time the punch blade 3, 4. In the first stage of the punch blade 3, 4 is pushed in from one end of the tube by moving the arm 5 in the axial direction of the tube 1 a tube center line C direction, the cutting edge of the center line of the tube in the area. Thrust final stage is advantageous to transfer dro-Tinter at the same time also in the radial direction, as shown in dashed line in Figure 4 ABi. The bayonet blade 3, 4 sinks in the tube wall plane of the cutting edge 4, as the cutting edge 4 span maksimiupotuksella at one end of the tube substantially corresponds to the outer diameter of the tube 1. When the punch blade 3, 4 have reached the end of its travel axial movement, the arm 5 takes place in the transmission perpendicular to the axial direction of the tube 1. In the illustrated case, this transmission direction of Bi in Figure 4 down to the corresponding first cut into the shape of the punch blade piece of pipe 2 7 one end of the mold parting line ensimmäi against the public side of the arc shape. Cutting Edge 4 bypass the shape of an arc at close range.

For the second cutting step bayonet blade is pulled out of the pipe end by moving the arm 5 in the axial direction away from the tube 1. Thereafter, the arm 5 is rotated around its axis 180 ° to the cutting edge 4 turns 180 °, after which the arm 5 is moved in the direction of arrow A so that the punch blade 3, 4 is pushed back in one end of the tube. Cutting Edge 4 is walk then provided to the center line C side with respect to the first section. Thereafter, the arm 5 and the punch blade 3, 4 are moved in the tube 1 to the center line C perpendicular to the direction B2, which is opposite to its previous transferring direction of Bi to give a second corresponding 4 the shape of the cutting piece cut to the pipe end against the forming cycle of the mold. In the case shown (Figure 5) the transfer direction B2 is up.

As shown in Figure 4, the punch cutting edge of the blade 4 is inserted into one end of the tube is immersed in the tube wall below the plane of the cutting edge 4 of the tube center line C and the pressure of the punch blade for cutting down corresponding to the shape of the cutting edge 4 from the piece of pipe at the bottom of the head. When the punch blade 3, 4 has been pulled out and turned by 180 °, is pushed again the pipe end in (Figure 5), so that the cutting edge 4 is again below the pipe center line C, wherein the second piece is obtained not cut off by raising the punch blade 3, 4 upwardly. Figure 5 is the lower edge of the cut end of the pipe piece 2 provides a space pistinterälle 3, 4. In this arrangement, the bayonet blade may be shaped so as to provide massive support close to the cutting edge 4 to the side of a plane of the cutting edge, which follows the rear of the cutting edge during the cutting transfer. Thus the sting of the blade in a sustainable fashion.

Naturally, the first and second shearing step can also be performed in opposite directions of transmission, so that the cutting edge 4 is inserted into the pipe end in the pipe above the centerline C and the punch blade is lifted up in the shape of the blade for cutting the arc-piece at the top end of the tube.

In the second step, when the punch blade 3, 4 has been turned 180 °, the cutting edge 4 is pushed over the pipe end in again the center line C and the pressure of the punch blade for cutting down a second piece in the shape of the cutting edge at the bottom end of the tube. Pruning can thus start as well as at the top end of the tube at the bottom. Figures 4 and 5 show an alternative in which the cutting is initiated at the bottom end of the tube.

In Figure 6 is shown cut tube 1 and the mold 7 supporting the outside of the apparatus. Two openable two-part mold 7 is supported on a turntable 6, which is pivotable about a vertical pivot axis 10 through 180 ° for transfer of the mold 7 from the charging station the cutting position and at the same time to move the second mold section of the position of the charging station. The link axle 10 on both sides of the deformable tube has one rear stop 11, which determines the position of the tube and hold the tube in place axially when the punch blade 3, 4 is pushed into the tube. 8 muotinpuoliskot holder to squeeze together and holds the mold in position 7 in the form of cuts in the pipe end. On the opposite side of the turntable 6 nostotarrain 9 to raise for the exchange of the mold 7, the upper half of the top tube. The second pipe is cut from the second mold is removed from already cut the pipe and the mold is inserted in the pipe to be cut. The holder 8 is calculated to keep the tube 1 onto the mold 7 supporting the mold during surgery. The holder 8 is raised for a period of six rotation of the turntable.

Although the preferred embodiment is only one of the punch blade for cutting the two steps can be used individually or in combination of two bayonet movable blades whose directions are opposite to each other pre Figures 4 and 5 a similar manner.

Claims (8)

A method of cutting a pipe end, in which method it cuts two ends (2) of curved edges from the end of the pipe by means of a punch cutter (3, 4) and a pad (7), and therefore the punch cutter has a bent cutter ( 4) and the pad has a shape arc corresponding to the arc of the cutter, and the cuts of pieces (2) are performed from the inside of the tube (1) outwardly in two subsequent cutting steps, the punch cutter (3, 4) being pushed into the end of the tube in the center line of the tube (C). ) direction, wherein the insert (4) lies at the center line (C) of the tube (1) and the punch insert is also moved transversely (Bi) in relation to the center line, the insert cutting a first piece towards the shape arc located on the first side of the die (7) of the dividing plane. , characterized in that after the cutting, the die cut is moved backwards and the die cut is turned in 180 ° or replaced by another die cut which is completely turned in 180 °, that the turned die cut is re-inserted into the end of the tube in the middle of the tube the cutting line (4) is at an adjusted distance relative to the center line (C) on the side of the first cutting, and that the cutting insert is moved transversely in relation to the center line in the opposite direction (B2) relative to the first flow direction (Bi ), the insert cutting a second piece against the shape arc located on the other side of the dividing plane (7). Method according to claim 1, characterized in that before the first transverse cutting movement (Bi), the cutting insert (4) is lowered in the wall of the pipe on the same side of the center line of the pipe where the cutting piece (2) is first located, and before the in the second cutting movement (B2), the cutting insert (3, 4) is pushed into the end of the tube (1) in a position where the plane of the insert (4) lies on the side of the center axis of the tube (C) from which the plane of the insert starts and goes past the center axis (C). the punch insert (3, 4) is moved to cut a second piece (2). A die cutting device for a pipe end, the device comprising a pad (7) for supporting the pipe (1) to be formed and a die cutting having a cutter (4) corresponding to the curvature of the piece (2) to be cut , characterized in that the chord of the cutting part in the curved inserts (4) of the punched cutter (3, 4) pushed into the end of the pipe (1) is larger than the inner diameter of the pipe (1) and that the pad (7) is on both sides of the the dividing plane of the cushion provided with moldings corresponding to the arc of the insert, and that the insert (4) is slidable into the pipe end in 180 ° facing positions and movable alternately in two opposite directions (Bi, B2), which are substantially perpendicular to the the center line (C) of the pipe (1). Device according to claim 3, characterized in that the die cutter (3, 4) has a solid support mass supporting the insert (4), the supporting material behind the insert seen in the direction of the cutting movement, the insert defining a flat surface. Device according to claim 3 or 4, characterized in that the cutting insert (4) is an arc in the form of a semi-circle or part of a circle which is the edge of a blunt projection, and that the radius of curvature of the cutting insert (4) is essentially the same or greater than the outer radius of the tube (1) to be cut. Device according to any one of claims 3-5, characterized in that the punch insert (3, 4) is fixed at the end of a rotary shaft (5), that the operating shaft (5) is movable in the direction of the center line (C) of the tube (1) for sliding. the punch insert (3, 4) into the end of the tube (1), so that the operating shaft (5) is movable substantially perpendicular (Bi) with respect to the direction of the center line of the tube (1) to cause the punch insert to cut from the tube end a piece corresponding to the insert (4). ), that the operating shaft (5) is rotatable 180 ° about its longitudinal axis, that the cutting insert (3, 4) is re-slid into the pipe end in a position turned in 180 ° and that the operating shaft (5) is movable in relation to the said flow direction opposite the flow direction (B2) to cut a second piece from the end of the tube. Device according to any of claims 3-6, characterized in that two two-part openable pads (7) are supported against a turntable (6) which is pivotable 180 ° around a vertical shaft (10) for moving the pads (7) from the loading position. ion to the cutting position and to move the second pad from the cutting position to the loading position and that on both sides of the shaft (10) there is a rear stop (11) for the tube (1) to be formed, which rear stop determines the position of the tube and holds the tube axially in place as the punch insert (3, 4) is inserted into the tube. Apparatus according to any one of claims 3-6, characterized in that the device has two two-part pads (7) which have in the plane of the pads a half groove corresponding to the diameter of the pipe to be cut, that there is at the other end edge of the pads (7), perpendicular to the partition plane, arc shapes corresponding to the arc to be cut centrally in relation to the groove contained in the partition plane, whereby sharp corners are formed at both sides of the partition plane at the point of intersection of the arc.