The method of fixing tubes
The invention relates to the processing of metals by pressure and can be used when attaching the tubes of heat exchangers. The ends of the tube profiles with education ends in the form of cylindrical sections, the mating conical transitional section. On the outer surface of the loaded section of the tip to form an annular ledge trapezoidal cross-section. The protrusion is formed in separable matrix with the annular groove of the stepped radial crimping of the length of the ending and its subsequent distribution donovania holes with simultaneous profiling of the inner surface of the loaded area. At step crimping of the length of the loaded area ending console feature to the edge of the ring grooves of the matrix and partially fill the volume of this groove material shaped ends, not affected by the radial crimping. In the process of distribution completely fill the pipe material volume of the annular grooves of the matrix. Then ending is installed in the hole of the tube with the annular grooves of trapezoidal and triangular cross-section, fix the pipe from possible displacements and fix. In achiev"ptx">
The invention relates to the field of metal forming, in particular to the process of fixing the tubes of heat exchangers using the effect of localized directional plastic deformation of the pipe material.
A known method of fixing tubes, including the installation of a heat pipe with one end in the tube hole, the fixation of the possible displacements, welded pipe end to the face of the tube with the subsequent expansion of the pipe by the application of compressive force to the inner surface, for example, mechanical rolling (see P. Doroshenko A. manufacturing Technology marine steam generators and heat exchangers, Leningrad, Sudostroenie, 1972, 143 S.).
To the main disadvantage of this method of fixing tubes should be attributed to the increased cost of production of the combined compounds. In addition, the known method has a limitation on the application, as not all of the material, forming a pair of connected elements are welded.
There is also known a method of fixing tubes, including the profiling of the pipe ends is sleduushee formation on the external surface of the loaded area profiled ends of the annular ledge of the trapezoidal cross-section, the installation of each ending in an orifice tube, made with annular grooves of trapezoidal and triangular cross sections, fixing pipes from possible movements and then pinning it in the hole in the tube by application of compressive force to the inner surface of the ending (EN 2171155 C2, 27.07.2001, 21 D 39/06 - prototype).
The disadvantage of this method is a significant dependence of the performance characteristics of the permanent connection from the aligned holes in tube sheets and annular grooves cut in them. The annular protrusion shaped ends having high strength characteristics, is placed in a corresponding annular groove hole tube with a variable on-orbit gap relative to the surface of the latter. In this case, the fastening of profiled ends of the pipe in the hole of the tube is associated with increased effort on deforming the tip of the tool. Formed ring density between the joined elements are determined by the intensity of local plastic deformation of the jumper tube, so as circumferential deformation of the pipe material in the ledge difficult.
The above Vesti tube grates from the nominal value.
Object of the invention is to provide such a method of fixing tubes, which would ensure quality ring densities between joined elements due to plastic deformation of the pipe material in the annular ledge.
The technical result is achieved in that in the method of fixing tubes, including the profiling of the pipe ends with the formation of edge lines containing cylindrical sections, the mating conical transitional section, the subsequent formation on the external surface of the loaded area profiled ends of the annular ledge of the trapezoidal cross-section, each ending in an orifice tube, made with annular grooves of trapezoidal and triangular cross sections, fixing pipes from possible movements and then pinning it in the hole in the tube by application of compressive force to the inner surface of the ending, according to the invention the formation of the external the loaded surface area of each profiled ends of the annular ledge of the trapezoidal cross-section is carried out in a split matrix with Kalki donovania her holes simultaneously profiling the inner surface of the loaded area, at this speed radial crimping of the length of the tail pipe is produced with maintenance console location of the length of the loaded area profiled ends to the edge of the ring grooves of the matrix and the partial filling of the annular groove by placing its material part of the profiled ends, not affected by the radial crimping and maintains its outer diameter, and in the process of distribution make final filling pipe material volume of the annular grooves of the matrix.
Implementation of the proposed method of fixing tubes repair option allows you to get a quality ring density between the joined elements and in cases where there are wide variations geometric dimensions of the annular grooves from the nominal values.
This is because, using the design of the profiled ends of the annular ledge of the relatively hardened material, create conditions of plastic deformation of the material (as in the radial and circumferential directions) in the annular ledge in the formation of permanent connection. As a result, the inner surface of the profiled for is not deteriorating the corrosion resistance.
The invention is illustrated by drawings, where Fig.1 shows the starting position of the segment split matrix and profiled end of the pipe with a larger geometrical dimensions on the external diameters; Fig.2 - stage end of the stepped radial crimping within the length of the profiled ends; Fig.3 - implementation phase low-speed tapered mandrel into the hole ends; Fig.4 - the end stage of forming an annular ledge introduction hole ending great degree mandrel; Fig.5 - connect the elements before the implementation of the pre-fixing pipe shaped tip in the hole of the tube; Fig.6 - end of the pre-fixing pipe in the hole of the tube; Fig.7 - initial position of the stepped mandrel and connected elements before final mounting of Fig.8 - stage formation of the bell on the edges of the holes of the tube; Fig.9 - the permanent connection of the tubes and tube sheets.
Variant implementation of the invention consists in the following.
Heat transfer pipe 1 (Fig.1) perform operations with the aim of preparing the outer surface of its ends to the profile: edit tronolane end of the tube, what pipe is fixed from possible movements and through hard punch to produce the distribution end to the external diameter greater than the diameter of the holes in the tube sheet holes, for example, for a pipe 252.5 mm outer diameter end after its distribution to equal...25,5 25,7 mm
Then the pipe is fixed from possible movements and, by moving the matrix with the speed of the working cavity on its end, perform a stepped radial crimping. As a result, three cylindrical section with diameter D1D2and D3mating conical transition sections. Pipe it shaped tip mounted in the hole of the split matrix consisting of three segments (Fig.1). The cavity formed by the segments when they are closing, contains an annular groove of trapezoidal cross-section. Carry out the fixing of the pipe from possible movements outside tooling (arrows).
Then make the closing segments of the matrix, causing a radial stepped crimping within part of the profiled ends, i.e. pureprofile her so into smaller external diameters of D4and D5. In the meter of D2and a console located to the edge of the ring grooves of the matrix is in the last volume, partially filling it (Fig.2). It should be emphasized that the stepped radial crimping, on the one hand, causes a lateral shift in the fabric of cylindrical sections, and on the other hand, forms the field of compressive stresses in the radial and tangential directions. Thereby form the stiffness of the deformation zone during subsequent operations on the pipe and eliminate the axial course of the pipe material.
In the hole profiled ending implement a stepped mandrel 3, which distributes the cylindrical section with an outer diameter of D3up to a diameter of the matrix, with the placement of Flexural deformation of the conical transition section in the volume of the annular grooves. Opposite the annular grooves of the matrix is formed an annular cavity (Fig.3).
Further axial movement of the stepped mandrel causes the influence of his greater speed to plastic for pipe material and the final formation of the annular ledge. Moreover, because of the relatively small deformation of the pipe material in the annular protrusion does not undergo large hardening. Moving large degree mandrel OGRANIChENNOI (Fig.4).
Then finally shaped ending set in the hole of the tube, controlling the correctness of the location of the pipe on the protrusion of the end-ends over the front surface of tube (Fig.5).
In the hole ending enter the case of the mechanical rolling and produce distribution plot (the action of the rollers rolling conventionally shown by arrows) ending with a minimum diameter of holes (Fig.6).
Contact deformation ending calls non-contact bending of the cylindrical control section ends with an outer diameter of D4CPC volume filling groove with a triangular cross-section.
The final fastening of the pipe in the hole of tube reach implementation in the hole ending stepped mandrel 5 (Fig.7). In this case, a small step to provide a distribution of the blade tips to the diameter of the hole in the tube sheet holes with the formation of lateral shifts in the canvas (shown in dashed lines) and the formation of the bell on the edges of the holes of the tube (Fig.8).
The permanent connection of the tubes and tube sheets has elevated service characteristics, where the density is achieved kolawale operations are performed on the second end of the pipe.
Pilot validation of the developed method was pinned steel (20) tubes with shaped ends in the tube sheets of steel 16GS thickness of 80 mm, an Initial geometrical dimensions of the tube were: outer diameter - 25 mm, wall thickness - 2.5 mm Outer surface of the pipe ends pre-profiled in industrial equipment hydraulic press, double action, developing maximum force of 0.6 MN. The cylindrical section ends with a minimum external diameter had to 23.8 mm, the maximum outer diameter of 25.6+0,05mm Conversion reached its reduction to the diameter of 25.3+0,05mm Width of the conical transition sections was equal to 2.0 mm
Pipe holes were produced with diameters equal to 25,35+0,05mm groove tube holes with triangular cross-section were: base - 6 mm, a depth of 0.3 mm, with a trapezoidal cross section: large base - 4.0 mm, the smaller base is 2.0 mm, a depth of 0.4 mm
Pre-fixing pipe in pipe hole was completed on a rolling stand firm “Indresco (USA) complete expanders, domestic production, and the final consolidation - dornbecher Saudi 0,2 MN.
Technological equipment for the production of tubes with shaped ends and hold them in place in the tube holes were made from tool steel WA with hardness after quenching HRC of not less than 56 units and precision of the Executive sizes according to the ninth degree.
The formation of a permanent connection with use of the tips that have shaped both external and internal surfaces, in combination with a bell on the edges of the holes of the tube provides guaranteed high performance characteristics of compounds; removing any defects that affect the operation of the tube bundle.
Tests for pulling tubes from the tube confirmed the increased strength characteristics of permanent joints (destruction occurred outside of fixing the original section of the pipe).
The density of connections in combination with high corrosion resistance provided 100% of their suitability to the requirements of production.
The invention is applicable in the manufacture of the tube bundles of heat exchangers in the oil refining, petrochemical, gas and other industries.
Ways is containing a series of cylindrical sections, the mating conical transitional section, the subsequent formation on the external surface of the loaded area profiled ends of the annular ledge of the trapezoidal cross-section, each ending in an orifice tube, made with annular grooves of trapezoidal and triangular cross sections, fixing pipes from possible movements and then pinning it in the hole in the tube by application of compressive force to the inner surface of the ending, characterized in that the formation on the outer surface of loaded area of each profiled ends of the annular ledge of the trapezoidal cross-section is carried out in a split matrix with the annular groove by a stepped radial crimping of the length of the ending and the subsequent distribution of ending donovania her holes simultaneously profiling the inner surface of the loaded area, with a stepped radial crimping of the length of the tail pipe is produced with maintenance console location of the length of the loaded area profiled ends to the edge of the ring grooves of the matrix and casting is subjected to radial crimping and maintains its outer diameter, and in the process of distribution make final filling pipe material volume of the annular grooves of the matrix.
FIELD: machine-assembly equipment for producing nuclear reactor fuel assemblies.
SUBSTANCE: proposed machine has pneumatic cylinder rod provided with its motion limiter and contactless sensor at drifting mechanism on through slit of bottom end part of fuel element; cone angle of drift-rod is 30 deg. and annular drilling diameter in each hole of auxiliary spacer grid equals nominal flare of fuel element end part sections internally drifted inside each annular drilling within upper nominal-size tolerance D = Hk, where D is annular drilling diameter; H is nominal flare; k is upper nominal-size tolerance.
EFFECT: enhanced quality of fuel assembly.
1 cl, 5 dwg
FIELD: plastic working of metals, namely by means of energy of electric explosion of metallic connector in condensed media.
SUBSTANCE: apparatus includes dielectric sleeve with transfer medium hydraulically insulated by means of rubber plugs. In cavity of said sleeve are arranged: rigid carcass in the form of two end walls mutually joined by means of metallic studs; and exploded metallic conductor. The last is divided by two parts connected one with other through electrode. Electrode rests upon dielectric sprockets and it is in the form of body of revolution whose shape is described by function defining length and diameters of electrode according to linear dimensions of deformed portion of tube. Relation of maximum diameter of central part of electrode to inner diameter of dielectric sleeve is in range 0.5 - 0.8. Curvilinear surfaces of end walls of exploded conductors are in the form of paraboloid. Boundary ends of exploded conductor are arranged in focal point of paraboloid.
EFFECT: more effective usage of energy of electric explosion of metallic conductor, enhanced quality and reliability of tube pressing-in, improved efficiency of apparatus.
4 dwg, 1 ex
FIELD: plastic working of metals, possibly tube expanding.
SUBSTANCE: tool includes clamp mechanism having clamp cylinder and spacing rod arranged in it. Tool includes housing in which compression spring is arranged in such a way that its one end rests upon housing and other end rests upon end of clamp cylinder; force working member mounted inside compression spring and made of shape memory alloy. One end of working member is secured to housing; its other end is secured to spacing rod. Spring and working member are made with possibility of creation in common system of forces in which direction of summed vector acting upon spacing rod depends upon temperature of working member. Increase of working member temperature till value exceeding that of reverse martensite conversion causes generation of efforts transmitted to spacing rod due to shortened length of working member.
EFFECT: lowered cost price of labor, enhanced efficiency of tool.
FIELD: plastic working of metals, possibly tube securing to tube walls of heat exchange apparatuses by means of directed plastic deforming of tube material.
SUBSTANCE: method comprises steps of placing tube in tube wall opening with annular recess at providing protrusion of tube end over front surface of tube wall; fixing tube against axial motion due to placing on part of its protruded end locking ring with threaded holes for screwing-in bolts and for forming local bulged portions on tube; profiling protruded end of tube; shaping annular thickened portion on tube arranged in annular recess of tube wall and shaping annular protrusion on front side of tube wall. After securing profiled end of tube circular welding of tube to tube wall is realized. Then tube is broached for expanding it in range of tube wall thickness value in zone of bulged portions and for creating plastic yielding of tube material relative to edge of opening at back side of tube wall.
EFFECT: improved quality of non-detachable tube-to-tube wall joint.
2 cl, 9 dwg
FIELD: plastic working of metals, possibly securing thin-wall small-diameter tubes to tube walls of heat exchange apparatuses with use of directed plastic deforming of tube material.
SUBSTANCE: method is realized for tube whose length exceeds desired one. Method comprises steps of subjecting tube material on tube end portions to heat treatment in order to enhance its plastic properties; placing tube in opening of tube walls and preliminarily fastening it due to placing ring on protruded tube end and expanding tube protruded end till diameter of annular recess of tube wall for receiving calibrated zone; applying axial compression effort to end of calibrated zone for forming thickened portion. Then tube is finally fastened in tube wall opening due to broaching its thickened portion and providing plastic yielding of tube material from thickened portion towards rear edge of tube opening. Diameter of opening formed in thickened portion is equal to initial diameter of tube. Tube material embraces rear edge of tube opening.
EFFECT: improved quality of formed joint.
FIELD: plastic working of metals, possibly expanding tubes in tube walls.
SUBSTANCE: rolling unit includes separating housing; cone expanding rollers having rolling bands, head end portion and tail end portion; windows for mounting them; spindle passing along axis of housing. Said windows are formed on separating housing uniformly along its perimeter with central angle 120° between adjacent windows whose axes are turned by predetermined angle relative to generatrix of housing. Said windows are arranged in lengthwise rows, three different-length windows in each row. Boundary windows of lengthwise rows of housing in each row and rollers mounted in them also have different length values. Length values of rolling bands of rollers and distance between rolling bands are determined according to relations given in specification. Total length of rolling band used for expanding is equal to summed length value of rolling bands of all three rollers in window of any lengthwise row and doubled distance between rolling bands of rollers in adjacent windows of each row.
EFFECT: enhanced effectiveness of works for making heat exchange equipment.
FIELD: power machine engineering, possibly manufacture of heat exchange apparatuses.
SUBSTANCE: method comprises steps of placing tube having annular shoulder on outer surface in flanged opening of tube wall till tube resting upon inner surface of said opening; forming surface of shoulder and inner surface of opening in such a way that to provide their matched joining; fixing tube against possible movement and fastening it in opening of tube wall due to performing zone-to-zone deformation of tube and flanging opening by means of pressure pad. Shoulder on outer surface of tube may be in the form of tore-like zigzag or fixed ring.
EFFECT: improved manufacturability of method, enhanced operational reliability and fluid-tightness of formed joint.
3 cl, 4 dwg
FIELD: plastic working of metal.
SUBSTANCE: method comprises assembling the heat exchanging pipes into a pipe bank with the use of intermediate cooling plates and interconnecting the pipes. The device comprises rod and rings provided with projections shifted with respect to the adjacent ring. The projections of each subsequent ring are shifted with respect to these of the previous one by means of rotation around the axis of the rod by a value of the space between the capillary passages.
EFFECT: enhanced strength.
7 cl, 5 dwg, 1 ex
SUBSTANCE: disclosed method consists in forming work-pieces of panels with running channels out of band by means of rolling in coils; in punching mouth and in separating work-pieces of panels in press. Prior to separating work-pieces of panels a window is punched out; the window is symmetrical relative to the line of separation of the work-pieces of the panels. Upon separating work-pieces in one punch the mouth of the panel is flanged in another punch, thereby forming a collar parallel in plane to side walls of the panel.
EFFECT: increased efficiency and upgraded quality of panels.
SUBSTANCE: there are implemented set-up labors on pipes - dressing, cutting sufficiently, finishing of external surface of ends, expansion - calibration of pipe end by rigid punch, cascading radial breaking-down of calibrated section by segments of split die. Herewith it is used matrix, containing finishing, preliminary etchings and working between them. Then it is reshaped calibrated section for maximal and minimal cogged sections and conic transition point between them, with following shaping compensation volume by means of burnishing of cavity of maximal cogged section. Additionally shaped edge line is formed by two compensation volumes in the form of doughnut and thickened section of cloth. Additionally collar is formed successively: at stage of cascade radial breaking-down - its external tapered surface, and at burnishing - intermediate compensatory volume in the form of thickened section of cloth of calibrated section with following giving to it of final shape of collar in finishing etching of matrix by means of shear lateral deformation in cloth of calibrated section at its radial annular overclamping. Thickened section of cloth in final form is formed by repeated burnishing of edge line cavity after receiving of collar with extrusion of pipe material into prliminary etching.
EFFECT: upgraded quality.