A kind of spin-on process
The present invention relates to a kind of spin-on process, belong to metal pipe material pressure processing technology field.
The powerful outside spinning of three spinning rollers is current topmost thin-wall tube-shaped element manufacturing process, there is spinning tonnage large, three spinning rollers can automatic centering, spinning Product Precision high, is widely used in the mould pressing of Thin-wall cylindrical part, the outer modal circumferential stiffening rib of band and small-angle part.Due to the structure of spinning machine and the feature of function, when spinning overlength (length more than 10 meters) thin-wall tube-shaped element, core must have sufficient intensity, rigidity and surface quality, the core of more than 10 meters manufactures difficulty, in spinning process, occur that in ultralong thin walled barrel type part demoulding difficulty and spin-forming procedure, mould is bowed, ultralong thin walled barrel type part one end transmitting torque in spinning process causes workpiece torsional deflection, ultralong thin walled barrel type part length is long due to reason generation flexural deformations such as deadweights, and material flows not smooth in rotary pressure deformation process, swell before spinning roller and excessively occur falling material, the problems such as Product Precision reduction.Existing cold-drawing technology can produce the tubing of more than 10 meters, but the form and position tolerances such as its wall thickness is large, evenness of wall thickness is poor, circularity and linearity are difficult to control; The existing cold rolling tubing only produced diameter and be less than the difficult-to-machine material of 200 millimeters, precision is high but efficiency is low.
A difficult problem is manufactured for solving ultralong thin walled barrel type part spinning process core mould, the problems such as demoulding difficulty, Xiao Zuoyi proposes to adopt floating core die in " tubular member shear spinning new technology---floating core modulus method " (forging technology the 5th phase in 1999), floating core die is shorter, adopt the stepped cylindrical structure of the band shaft shoulder, it is inner that floating core die is placed on spinning blank, core is axially being subject to the axial thrust that suffered by frictional force and the shaft shoulder, spinning roller applies, the effect of the axial thrust that spinning roller applies suffered by the shaft shoulder, core is constantly travelled forward in spinning process, relative with spinning roller position fixing, keep the continuity of distortion.But the floating core die of this version, the internal diameter of spinning blank will hold the shaft shoulder, and rotary pressing processing amount is large; Simultaneously when spinning, floating core die rotate may with spinning blank disalignment, the lengthwise movement of spinning blank is obstructed and tube wall thickness uneven.
In a word, the function restriction of existing spinning machine and process are difficult to revolve ultralong thin walled barrel type part processed (being greater than 5 meters), can not meet national defense industry and other civilian industry low cost, high efficiency, high accuracy, high-quality product requirement.
Summary of the invention
The object of the invention is to overcome prior art deficiency, provide the spin-on process that a kind of precision is high, yield rate is high, production efficiency is high.
Technical solution of the present invention: a kind of spin-on process, comprises the following steps:
The first step, spinning blank prepares,
Processing two ends are with the spinning blank of the straight tubular construction of keyway;
The concrete size of spinning blank be set as techniques well known, content refer to National Defense Industry Press publish statement first wait work " shear spinning technique and equipment ", specific as follows:
(1) spinning blank wall thickness t is determined
According to the spinning force size of spinning machine, the wall thickness according to spinning product requires, the limit attenuating rate of material, the arrangement of spinning pass etc. of institute's spinning calculate the wall thickness t of spinning blank
(2) the theoretical length L of blank is determined
According to the length of long tubular workpiece final product structure, wall thickness and the spinning blank wall thickness t that determines above
1, calculate blank theoretical length according to flow formed part equal-volume principle, and consider that the theoretical length L of the process allowance determination blank installing location is reserved at spinning blank two ends
(3) the external diameter Φ D of spinning blank is determined
2and internal diameter Φ D
According to the external diameter of fixing short core, consider the requirement of spinning blank by fixing short core, increase surplus.Spinning blank internal diameter Φ D
1be generally the external diameter Φ D of fixing short core
0the surplus of about+0.3mm; Spinning blank external diameter Φ D
2be generally spinning blank internal diameter Φ D
1.The external diameter Φ D of fixing short core
0determination, consider according to the mass runoff that rises of diameter after the internal diameter of long tubular workpiece final product structure and spinning, the internal diameter being generally final product structure deducts the mass runoff that rises of diameter.
Second step, spinning machine prepares,
Described spinning machine comprises lathe bed, longitudinal feed mechanism, fixing short core and rotary wheel mechanism, described rotary wheel mechanism comprises spinning roller and spinning roller transverse feed mechanism, spinning roller is fixed on lathe bed by spinning roller transverse feed mechanism, lengthwise position is fixed, fixing short core is vertically fixed in spinning roller position by core pull bar, described longitudinal feed mechanism is two covers that structure is identical, be arranged on the two ends of rotary wheel mechanism respectively, described longitudinal feed mechanism comprises leading screw, upper screw, lower leading screw, lower screw, main spindle box, main shaft, spindle drive motor and connector, main shaft and spindle drive motor are arranged in main spindle box, upper screw is fixedly connected with main spindle box respectively with lower screw, upper screw and lower screw are respectively equipped with a length feed motor, connector is installed in the end of main shaft,
Described fixing short core comprises core mandrel, core end cap, conical bearing and core body, core mandrel penetrates core body interior, to be rolled with core body by the conical bearing at two ends and coordinate, core mandrel one end is fixedly connected with core pull bar, core end cap is arranged on core body end, is sealed in by conical bearing in the shoe cream room that formed by core mandrel and core body.
Described upper leading screw and lower leading screw are diagonal layout on main spindle box.
3rd step, rotary pressure process parameter is selected, and determines spinning program;
Rotary pressure process parameter selects to comprise spinning pass, reduction, roller working radius, feed rate, (rotary pressure process parameter is chosen as techniques well known for spinning roller wrong distance amount, the speed of mainshaft etc., the statement that particular content refers to National Defense Industry Press's publication first waits outstanding " shear spinning technique and equipment "), based on rotary pressure process parameter and track, work out spinning program.
4th step, spinning blank is installed,
A4.1, spinning blank are placed on the bracing or strutting arrangement of spinning machine by lifting device;
A4.2, be fixedly connected with one end of spinning blank by the longitudinal feed mechanism away from core pull bar, longitudinal feed mechanism drives spinning blank to move and pass fixes short core;
A4.3, another set of longitudinal feed mechanism move, and be fixedly connected with the other end of spinning blank, bracing or strutting arrangement falls;
5th step, carries out spinning according to the spinning program of the 3rd step setting,
A5.1, determine initiatively longitudinal feed mechanism, another set of is driven longitudinal feed mechanism;
Principal and subordinate move longitudinal feed mechanism really normal root according to spinning process need set, the factor such as dextrorotation or derotation is adopted to determine primarily of the direction of length feed, spinning, wherein a set of is active longitudinal feed mechanism, another set of be just driven longitudinal feed mechanism, and spinning process needs change principal and subordinate to move longitudinal feed mechanism can to exchange flexibly.
A5.2, principal and subordinate move the main shaft drives spinning blank synchronous rotary of longitudinal feed mechanism and vertically move, make spinning blank to longitudinal original position of spinning procedure stipulation, spinning roller transverse feed mechanism drives spinning roller to be fed in the horizontal original position of spinning procedure stipulation;
A5.3, spinning blank synchronous rotary under driving and driven main shaft drives, spinning blank drives length feed by active longitudinal feed mechanism in rotary course, and driven longitudinal feed mechanism speed automatically adapts to follow initiatively longitudinal feed mechanism and vertically moves;
The length feed machine operation of driven longitudinal feed mechanism is under maximum (top) speed mode of operation, and the speed that realizes automatically adapts to follow initiatively longitudinal feed mechanism and vertically moves.By digital control system, the speed of driven longitudinal feed mechanism is set as that the speed of length feed motor is the highest, be generally greater than operating rate order of magnitude, can meet the demand of speed adaptive.
Driven longitudinal feed mechanism can realize spinning with tension simultaneously, and length feed motor is set as permanent moment of torsion by digital control system, makes driven one end of spinning blank by identical tension.The mode that the direction of identical tension is adopted by spinning is determined, according to derotation spinning, initiatively the direction of motion of longitudinal feed mechanism is contrary with spinning blank material flow direction, the identical tension that driven longitudinal feed mechanism is applied to is with initiatively longitudinal feed mechanism length feed direction is identical, and the identical tension optimum range that driven longitudinal feed mechanism is applied to is σ
2~ 0.5 σ
2for the yield strength of spinning blank material; According to dextrorotation spinning, initiatively the direction of motion of longitudinal feed mechanism is identical with spinning blank material flow direction, the identical tension that driven longitudinal feed mechanism is applied to is with initiatively longitudinal feed mechanism length feed direction is contrary, and the identical tension optimum range that driven longitudinal feed mechanism is applied to is σ
2~ 0.5 σ
2for the yield strength of spinning blank material.
A5.4, fixing short core rotate under the effect of the horizontal spinning force of spinning roller, and spinning blank rotates the gap moved longitudinally through between spinning roller and fixing short core, realizes the spinning of a passage of workpiece;
A5.5, carry out sofening treatment by after the workpiece of a passage spinning unloads;
The sofening treatment of workpiece is the hardness reducing material, and increase plasticity, generally adopt heat treatment, sofening treatment is techniques well known, and concrete heat treated temperature is determined by material category.
6th step, repetition the 4th step and the 5th step are until complete the spinning of all passages.
The present invention's beneficial effect compared with prior art:
(1) the present invention adopt spinning roller longitudinally fixing, rotation limit, spinning blank limit vertically moves, core is very short and the longitudinal technological measure such as fixing, spinning blank two ends synchronous rotary, meets the integral spinning forming of ultralong thin walled cylindrical shell;
(2) the present invention adopt structure identical two cover longitudinal feed mechanisms, spinning with tension can be realized very easily, simultaneously according to spinning process and production requirement, principal and subordinate's feed mechanism can set flexibly, thus the identical tension direction making driven feed mechanism apply changes flexibly, spinning blank can be subject to thrust in one end, and one end vertically moves by pulling force, or two ends vertically move by pulling force simultaneously;
(3) the present invention adopts spinning blank synchronous rotary technique in two ends in longitudinal movement, decreases long tubular workpiece torsional deflection, improves the precision of product;
(4) core of the present invention's employing is very short and longitudinally fixing, under spinning force effect, conical bearing is adopted to realize core body along with spinning blank synchronous rotary, solve great diameter and long thin-wall tube-shaped element spinning mandrel and manufacture a difficult problem, the demoulding difficulty and spin-forming procedure in mould bow, the problems such as vibration, avoid simultaneously and adopt existing floating core die, the defect of retard motion and tube wall thickness inequality when spinning blank vertically moves, between spinning process core mould body and spinning blank, gap is less, the processing capacity of spinning blank circumference is little, for mould pressing high-precision product provides guarantee,
(5) the present invention adopts constant force feeding speed adaptive technology, solve that ultralong thin walled barrel type part length is long produces flexural deformation due to the reason such as deadweight, material flow in rotary pressure deformation process smooth, before spinning roller, swell the excessive problem such as material, Product Precision reduction that occurs falling;
(6) the present invention adopts screw, screw structure to realize vertically moving, and structure is simple, and the leading screw of longitudinal feed mechanism adopts double lead-screw diagonal to arrange on main spindle box, the problem such as to creep under the disturbing moment of elimination main spindle box and heavy duty;
(7) the present invention can be used for Thin-walled Straight cylindrical work pieces, the band ultralong thin walled cylindrical shell of outer modal circumferential stiffening rib and small-angle thin-wall barrel mould pressing, combination property is good, forming accuracy is high, and cost is low, avoids the technical barriers such as ultralong thin walled part solder design distortion.
Figure of description
Fig. 1 is spinning machine topology layout schematic diagram of the present invention;
Fig. 2 is spinning machine longitudinal feed mechanism structural representation of the present invention;
Fig. 3 is Fig. 2 B-B direction of the present invention view;
Fig. 4 is rotary pressing processing schematic diagram of the present invention;
Fig. 5 is that spinning machine of the present invention fixes short core mold structure schematic diagram;
Fig. 6 is present invention process flow chart;
Fig. 7 is spinning blank front view of the present invention;
Fig. 8 is spinning blank side view of the present invention.
Detailed description of the invention
Below in conjunction with accompanying drawing and instantiation, the present invention is described in detail.
Processing super long thin-wall tube-shaped element, its wall thickness 5mm, factory length L are 8000mm, and product external diameter φ D is 504mm, and material is OCr18Ni9 stainless steel alloy.
Preparation process as shown in Figure 6, is realized by following steps:
1, spinning blank is prepared
(1) Blank Design
Be straight tubular construction as shown in Figure 7,8 by spinning Blank Design, its wall thickness t
1according to the spinning force size of spinning machine, the wall thickness of spinning product requires, the limit attenuating rate of material, the design of spinning pass etc. of institute's spinning calculate the wall thickness t of spinning blank
1, blank length L
1reserved process allowance COMPREHENSIVE CALCULATING gained is also considered, the wall thickness t of its blank according to equal-volume computational methods
1=23mm, internal diameter Φ D
1be designed to 494mm, external diameter Φ D
2be designed to 540mm, length L
1for 1960mm, two ends process allowance is respectively 80mm.
(2) spinning blank processing
By the spinning blank requirement according to design of the seamless tubular goods purchased from producer, be processed into size, the shape of requirement by method for turning, inner circle falls 2 × 30 ° of chamferings, is convenient to blank and installs, the uniform some installing holes 81 of spinning blank two ends circumference, for being connected with connector.
Spinning blank machining-size, required precision are as follows:
Blank thickness: 23mm
Blank external diameter: 540mm
Blank internal diameter: 494mm
Blank length: 1960mm
Blank both sides flatness :≤0.2mm
Wall thickness tolerance :≤0.2mm
Diameter tolerance :≤0.3mm.
Two ends keyway: every 4, one end arc keyway, long 50mm, wide 20mm, dark 23mm.
2, spinning machine prepares
Spinning machine used herein as shown in Figure 1, comprise lathe bed 11, rotary wheel mechanism, bracing or strutting arrangement 7, longitudinal feed mechanism and fixing short core 12, rotary wheel mechanism comprises spinning roller 9 and spinning roller transverse feed mechanism 10, spinning roller 9 is fixed on lathe bed 11 by spinning roller transverse feed mechanism 10, lengthwise position is fixed, fixing short core 12 pierces in spinning blank 8, is vertically fixed in spinning roller 6 position by core pull bar 4, fixing short core 12 and spinning roller 9 constant in spinning process lengthwise position.
Lathe bed 11 is arranged above and is connected various mechanical part and guide rail, and bearing various force and work can realize, the movement of the parts such as main spindle box on its guide rail, and lathe bed is connected with ground by fang bolt on the other hand, improves system stiffness.Lathe bed 11 is casting or Welding Structure, considers the problems such as manufacture, transport, multistage processing can be divided into finally to be rigidly connected and form.
Bracing or strutting arrangement 7 supports fixing short core 12 and spinning blank 8 loads and unloads, and is elevated and is driven by hydraulic jack.Spinning roller traverse feed servo-drive system 10 drives three 120 ° uniform spinning roller 9 traverse feeds, interpolation mutual to longitudinal feed mechanism, forms the processing trace curve of spinning roller.Spinning roller traverse feed servo-drive system 10 adopts electrohydraudic servomechanism to drive three 120 ° uniform oil cylinders, and cylinder rod is fixed, and cylinder body moves and promotes gliding mass and rotary wheel base transverse shifting, and grating scale detects feedback, forms closed-loop control system.When spinning blank 8 rotates while when moving longitudinally through the gap of the setting between spinning roller 9 and fixing short core 12, spinning blank 8 wall thickness is thinned, length elongation, achieves spinning blank 8 mould pressing, as shown in Figure 4.
Longitudinal feed mechanism is two covers that structure is identical, the two ends of rotary wheel mechanism are installed respectively, wherein a set of is active longitudinal feed mechanism, another set of is driven longitudinal feed mechanism, the dynamic normal root really of principal and subordinate determines according to technique, initiatively longitudinal feed mechanism vertically moves and drives spinning blank to move, and moving direction is by technique initialization, and driven longitudinal feeding device must be followed and be moved and speed adaptive.
During spinning, initiatively longitudinal feed mechanism vertically moves with spinning blank, driven longitudinal feed mechanism can realize spinning with tension, the length feed machine operation of driven longitudinal feed mechanism is under permanent moment of torsion maximum (top) speed mode of operation, follow initiatively longitudinal feed mechanism with making driven longitudinal feed mechanism speed adaptive vertically move, be applied to spinning blank driven one end identical tension simultaneously.The identical tension that driven longitudinal feed mechanism applies is determined according to spinning process with the direction that vertically moves of active longitudinal feed mechanism, identical tension (driven longitudinal feed mechanism) is less than active force (initiatively longitudinal feed mechanism), when both directions are identical, spinning blank one end is by thrust, and one end vertically moves by pulling force; When both directions are contrary, spinning blank two ends vertically move (moving method is active direction of feed) by pulling force simultaneously.
The tension that identical tension produces is set to σ usually
2~ 0.5 σ
2for the yield strength of spinning blank material, special thin-wall workpiece selects the upper limit 0.5 σ
2.Identical tension size is determined by the torque of setting length feed motor, the speed of driven longitudinal feed mechanism is set as the permanent torque condition of length feed motor by digital control system under, speed is the highest, generally be greater than operating rate order of magnitude, the demand of speed adaptive can be met.
The identical tension that driven longitudinal feed mechanism applies and active longitudinal feed mechanism vertically move direction identical time, identical tension optimum range is σ
2~ 0.5 σ
2; The identical tension that driven longitudinal feed mechanism applies and active longitudinal feed mechanism vertically move direction contrary time, identical tension optimum range is σ
2~ 0.5 σ
2for the yield strength of spinning blank material.
Longitudinal feed mechanism is as Fig. 2, shown in 3, comprise leading screw 2, upper screw 13, lower leading screw 3, lower screw 14, main spindle box 5, main shaft 15, spindle drive motor and connector 6, main shaft 15 and spindle drive motor are arranged in main spindle box 5, upper leading screw 2, one end of lower leading screw 3 is fixedly mounted on lathe bed 11 by support 1, the other end is fixedly mounted on spinning roller transverse feed mechanism 10, upper screw 13 is fixedly connected with main spindle box 5 respectively with lower screw 14, upper screw 13 and lower screw 14 are respectively equipped with a length feed motor, screw is driven to drive main spindle box 5 to vertically move along leading screw, connector 6 is installed in the end of main shaft 15, connector 6 other end is connected with spinning blank 8 one end, the main shaft that principal and subordinate moves longitudinal feed mechanism is coaxial, principal and subordinate makes spinning blank two ends synchronous rotary by connector when moving the spindle synchronous rotation of longitudinal feed mechanism.
Main spindle box adopts monoblock cast case structure, and main motor current is determined according to load design, and motor works operations below rated power, makes that the motor feels hot and measure to be reduced to minimum.The speed of mainshaft has stepless time adjustment, uniformly linear function, meets the requirement of spinning process.Connector is heavy wall cylindrical part, and one end is that short wimble structure is connected with short cone of main shaft, and the other end is located by internal diameter and pin is connected with spinning blank one end.
Longitudinal feed mechanism adopts rotation limit, screw limit to move drive shaft case and vertically moves, ball-screw non rotating, and encoder detects feedback, forms closed-loop control system.Two ball-screw is adopted to arrange at main spindle box diagonal, the problem such as to creep under eliminating the disturbing moment of main spindle box and heavy duty.
Fixing short core 12 as shown in Figure 5, comprise core mandrel 1201, core end cap 1202, conical bearing 1203 and core body 1204, it is inner that core mandrel 1201 penetrates core body 1204, to be rolled with core body 1204 by the conical bearing 1203 at two ends and coordinate, core mandrel 1201 one end is fixedly connected with by flange with core pull bar 4, the other end is fixed by nut 1205, core end cap 1202 is by two, be arranged on the two ends of core body 1204 respectively, conical bearing 1203 is sealed in the shoe cream room 1207 formed by core mandrel 1201 and core body 1204, core body 1204 is processed fuel feed hole 1206.
Fixing short core 12 is vertically fixed in spinning roller 9 position, spinning blank 8 (long thin-wall tube-shaped element) is placed in inner during spinning work, because the frictional force produced between the effect of spinning force and spinning blank 8 drives the passive rotation of core body 1204, bear the horizontal spinning force of three spinning rollers and dynamic balance.
Fixing short core 12 adopts alloy tool steel material manufacture, two groups of bearings 1203 of built-in carrying cross force and longitudinal force, core mandrel 1201 non rotating, by the passive rotation of frictional force core body 1204.Core mandrel 1201 and core pull bar 4 are rigidly connected, and bear longitudinal force, determine lateral attitude during work by spinning blank 8 and three horizontal spinning rollers.
3, spinning process is selected
Spinning pass designs, according to spinning blank wall thickness t according to the working ability of the limit attenuating rate of OCr18Ni9 material, raw material preparation and spinning machine
1=23mm, is divided into three passage mould pressings.First passage reduction is the 30.4%, second passage reduction be the 43.8%, three passage reduction is 44.4%.
According to institute's spinning blank wall thickness, roller working radius is 6mm;
Feed rate is selected: the first passage is 0.8mm/rpm, and the first passage is 1mm/rpm, and the first passage is 1.5mm/rpm;
Three spinning rollers are wrong apart from measuring as being 5mm;
Speed of mainshaft 60rpm.
4, spinning blank is installed (as shown in Fig. 1,4, left side is active longitudinal feed mechanism)
Spinning blank 8 is placed on bracing or strutting arrangement 7 by lifting device, first spinning blank 8 right-hand member key is installed on driven (right side) connector 6 connector, driven (right side) main spindle box 5 drives spinning blank 8 to be moved to the left and passes fixing short core 12, initiatively main spindle box moves right, spinning blank 8 left end is installed on active connector, bracing or strutting arrangement 7 falls, and spinning blank installs.
Specific operation process is as follows:
(1) lengthwise position of regulation is moved to according to establishment spinning program spinning blank;
(2) start spinning according to spinning program, spinning blank two ends synchronous rotary, three spinning rollers start pre-rotation, and cooling fluid begins to cool down, the horizontal servo feed of spinning roller;
(3) initiatively longitudinal feed mechanism drives spinning blank to vertically move, and spinning blank 8 rotates the gap of the setting moved longitudinally through between spinning roller 9 and fixing short core 12.
(4) according to after spinning program finishes execution, bracing or strutting arrangement rises and supports workpiece.The dismounting left side key that is connected with spinning blank of connector, right side main spindle box drives spinning blank to move right disengaging floating core die, and the key that on the right side of dismantling, connector is connected with spinning blank, hangs tight workpiece with crane and hang away.
(5) after the sofening treatment of workpiece, then be installed on spinning machine, carry out second, third passage spinning.
6, following process
Be cut two ends surplus after benchmark centering with external diameter by product, product is met design requirement.
The unspecified part of the present invention is known to the skilled person technology, and the statement that can refer to National Defense Industry Press's publication first waits " shear spinning technique and the equipment " of work.