CN201693117U - Double-post inclined prestressed stand for free forging hydraulic press - Google Patents

Double-post inclined prestressed stand for free forging hydraulic press Download PDF

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Publication number
CN201693117U
CN201693117U CN2010201748303U CN201020174830U CN201693117U CN 201693117 U CN201693117 U CN 201693117U CN 2010201748303 U CN2010201748303 U CN 2010201748303U CN 201020174830 U CN201020174830 U CN 201020174830U CN 201693117 U CN201693117 U CN 201693117U
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column
pull bar
hollow rectangle
forging hydraulic
stand
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Expired - Lifetime
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CN2010201748303U
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郭玉玺
薛峰
毛春燕
姚祖康
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Taiyuan Heavy Industry Co Ltd
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Taiyuan Heavy Industry Co Ltd
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Abstract

The utility model discloses a double-post inclined prestressed stand for a free forging hydraulic press and relates to a forging hydraulic press. The utility model solves the problems of lower integral rigidity, fatigue resistance, unbalance loading resistance and process adaptability of the conventional stand. The double-post inclined prestressed stand for the free forging hydraulic press is characterized in that upright posts are two hollow rectangular structures; a plurality of high-strength pull rods are arranged in the upright posts; both ends of the pull rods pass through an upper cross beam and a lower cross beam; the upper cross beam and the upright posts are embedded together by rectangular positioning keys; the lower cross beam and the upright posts are embedded together by the rectangular positioning keys; a preloaded tensile force is generated on the pull rods along the length direction by preloaded nuts and simultaneously preload pressure is applied to the upper cross beam, the lower cross beam and the upright posts so as to form the double-post prestressed combination stress stand; and the centroid connection line of the two hollow rectangular upright posts is inclined by an angle alpha relative to the center line of the movement direction of a worktable of the press. The double-post inclined prestressed stand can be used for the free forging hydraulic press, can be also used on a vertical hydraulic press suitable for the process and can improve the conventional forging press.

Description

Free-forging hydraulic twin columns inclined type prestressed stand
Technical field
The utility model relates to free-forging hydraulic, particularly the frame of free-forging hydraulic.
Background technology
Free-forging hydraulic is the key equipment that forging industry is produced forging.Traditional free-forging hydraulic is the non-full prestressing rack constructions of three beams, four cylinders, under abominable forging operating mode, must bear the alternate load of unidirectional big amplitude, usually causes the frame high vibration and rocks when quick loading and unloading suddenly.Circular Zhang Lizhu is not only as frame but also as pull bar, also as the guide way of moved cross beam, not only bear the axial tension of full tonnage constantly, always under the unidirectional alternation tension of big amplitude, work, during eccentric the forging, also to bear the lateral thrust and the moment of flexure of moved cross beam, and the basic loads such as angle moment of flexure that act on inboard hold-down nut place owing to upper and lower beam deformation.Simultaneously, the uneven wear and the guiding clearance that cause owing to the some contact stress state of moved cross beam circle guide pin bushing increase, and two root posts of either side all can not be evenly stressed, promptly can cause single upright column to bear eccentric load.Thereby circular Zhang Lizhu becomes the part of the destructible of hydraulic press, and it is of common occurrence that the example of fracture takes place Zhang Lizhu.
In recent years, what have is applied in the oil pump direct drive system on the non-full prestressing frame of above-mentioned three beams, four cylinders simply, or welded three beams, four column type conventional oil press are used as forging press, cause weld cracking, oil cylinder leakage of oil, cause press operation and maintenance cost higher.
What have has only made four cylinders into square column, but its stress, integral rigidity and fatigue resistance do not obtain radical change; Though what have has made the full prestressing frame into, owing to prolong, still can not improve cross sectional moment of inertia and the bending rigidity that the press center line is appointed two root posts of both sides with traditional four-column type structure, also have the danger that a root post bears offset loading force.Simultaneously, the four-column type structure still exists the unfavorable operating environment as the traditional water press: poor, the not accessible center of Technological adaptability, steel ingot turnover space is little, operability and visual difference etc.
Summary of the invention
The utility model purpose is to overcome the shortcoming of prior art, a kind of free-forging hydraulic twin columns inclined type prestressed stand is provided, it is relatively poor to solve the non-full prestressing frame of traditional three beams, four cylinders integral rigidity, fatigue resistance, anti-bias load ability and Technological adaptability, and the high problem of press maintenance cost.
Concrete technical scheme of the present utility model is:
A kind of free-forging hydraulic twin columns inclined type prestressed stand, comprise: column, entablature, sill and pull bar, it is characterized in that: described column is a kind of hollow rectangle column, described hollow rectangle column is two, many high strength pull bars place two described hollow rectangle columns, described entablature is passed at the two ends of described pull bar, sill, between described entablature and the described hollow rectangle column, described sill adopts the rectangle positioning key to be embedded in respectively between described hollow rectangle column, pretightning force and pre-clamping method according to design code, make on the described high strength pull bar total length by pre-load nut and to produce prefastening force, simultaneously to described entablature, sill and described hollow rectangle column apply preload pressure, thereby constitute the stressed frame of twin columns prestressing combination; The center line of the relative press bed moving direction of centre of form line of two described hollow rectangle columns becomes a α angle to arrange.
Two described hollow rectangle columns are the rectangular cross section of hollow on total length, and both ends are the structure of overhanging, and the angle α of the center line of the relative press bed moving direction of its centre of form line is between 55 °~75 °.
Place the quantity of the described high strength pull bar of every described hollow rectangle column, can select 5,6,7,10,16 according to the press tonnage, the diameter of every described high strength pull bar between φ 160~φ 240mm, the allowable stress 〉=700MPa of material, safety coefficient>2.5.
Described high strength pull bar is near the column wall, to the inside, the front and back side arranges that the arrangement form of described high strength pull bar has two rows at least.
Orthogonal wear-resisting guide plate is installed around two described hollow rectangle columns.
Described rectangle positioning key has 4 groups 16, respectively between described entablature and the described hollow rectangle column, be cross between described sill and the described hollow rectangle column and arrange.
The utility model compared with prior art has following advantage and beneficial effect.
The utility model is different from the stressed frame of forging the free-forging hydraulic that factory now uses, adopt the free-forging hydraulic that the utility model constituted, the variation amplitude of bar stress only is 15% of a maximum load stress, the prestressing force deviation is lower than 3%, and more traditional three beams, four cylinder hydraulic presses have improved press integral rigidity, fatigue resistance and reliability.Simultaneously, also have good press performance and technological operation.
Principle of the present utility model and structure not only can be applied to the free-forging hydraulic of various tonnages, and can be applied on the vertical hydraulic press of all suitable technologies, and can transform traditional forging press, thereby bring many beneficial effects: can reduce weight of equipment, reduce investment cost, reduce the occupation area of equipment and the melt pit degree of depth, Equipment Foundations have been simplified, factory building height and width have been reduced, reduced the driving span, plant working area and height space are fully used, have reduced maintenance cost etc.The utility model will directly cause a kind of realization with modern free-forging hydraulic of energy-saving and cost-reducing advantage.
Description of drawings
Fig. 1 is a structural representation of the present utility model;
Fig. 2 is that the stressed frame of twin columns inclined type of the present utility model is arranged schematic diagram;
Fig. 3 is the layout schematic diagram of Duola's bar of the present utility model;
Fig. 4 is a twin columns inclined type frame pretightening program schematic diagram of the present utility model;
Fig. 5 is prestressing combination frame pull bar of the present utility model and column (beam) power-deformation pattern.
The utility model is elaborated by embodiment below in conjunction with accompanying drawing.
The specific embodiment
As shown in Figure 1, a kind of free-forging hydraulic twin columns inclined type prestressed stand is mainly by sill 1, two hollow rectangle columns 2, entablatures 4 with place the high strength pull bar 5 of hollow rectangle column and pre-load nut 7 to form.Described hollow rectangle column 2 is two, high strength pull bar 5 places two described hollow rectangle columns 2, and pass described entablature 4, sill 1, between described entablature 4 and the described hollow rectangle column 2, between described sill 1 and the described hollow rectangle column 2, be the rectangle positioning keys 3 that cross arranges by 4 groups 16 entablature 4 and sill 1 are embedded in securely with two hollow rectangle columns 2.
Pretightning force and pre-clamping method according to design code, make on described high strength pull bar 5 total lengths by pre-load nut 7, packing ring 6 and to produce prefastening force, simultaneously described entablature 4, sill 1 and described hollow rectangle column 2 are applied preload pressure, thereby constitute the stressed frame of twin columns prestressing combination.
Place the quantity of the described high strength pull bar 5 of every described hollow rectangle column 2, can select 5,6,7,10,16 according to the press tonnage, the diameter of every described high strength pull bar 5 between φ 160~φ 240mm, the allowable stress 〉=700MPa of material, safety coefficient>2.5.
As shown in Figure 3, the arrangement principle of high strength pull bar 5 is as close as possible column walls away from neutral axis, to the inside, the front and back side distributes.The quantity and the arrangement form of described high strength pull bar 5 have: 3+2,4+2,4+3,4+2+2,4+4+2,6+4+6.
Orthogonal wear-resisting guide plate 9 is installed around two described hollow rectangle columns 2.
As shown in Figure 1, 2, whole frame seat is on two integral type foundation beams 8, the centre of form line of two described hollow rectangle columns 2 (Y-axis line) center line of press bed moving direction (X-axis line) relatively becomes the α angle tilting, and this angle [alpha] is between 55 °~75 °.By 8 cover overlength foundation bolts 10 with sill 1 and foundation beam 8 together with the basis in the ground anchorage anchoring.
Become the calculating of tension force pull bar pretightning force
The computational methods that become tension force pull bar pretightning force are, if every root post has n root pull bar, then the pretightning force P of i root pull bar iFor:
P i=K (n-i)P j
P in the formula j---the every final pretightning force that requires of pull bar, after promptly all pretension finishes, the tensile force that pull bar should reach.
The natural number of permutations of pretension order in the i----heel post.
K----is the stiffness coefficient of pull bar and column and upper and lower crossbeam, for the hydraulic press structure of determining,
K is a constant.
Twin columns inclined type frame pretightening program
Adopt the shared cover super-pressure pump device of two cover pre-load nuts, according to orientation shown in Figure 4 and number order, two pull bars of the adjacent numbering on each pretension left and right pillar simultaneously, and a pretension puts in place.
(1) calculating of pre-load nut oil cylinder power
According to becoming the pre-clamping method of tension force, calculate every pull bar required pulling force and working medium pressure of pre-load nut oil cylinder when pretension.
(2) apply the preceding inspection of pretension
According to the drawing requirement, check that the gap between each nut and the crossbeam backing plate meets the requirements; According to the electrical measurement embodiment, foil gauge and lead and metering device all are in place; The precision of frame is measured and adjusted, meet figure paper size and required precision.
(3) by orientation shown in Figure 4, pull-rod nut is numbered respectively, carry out pretension in proper order according to two pull bars of the adjacent numbering on each while pretension two root posts.
(4) successively left and right sides pull-rod nut is carried out pretension by Fig. 4 number order, make the meter pressure of pre-load nut all reach the pressure of regulation.Each tightens pull-rod nut from the opening part of splicing sleeve.
(5) measure stretch value and amount of recovery oil pump release after, the then respectively record of pull bar when pretension respectively.
(6) check the frame precision, locking device is installed.
Be further described with regard to concrete technical scheme of the present utility model below:
1) a kind of twin columns inclined type prestressed stand of free-forging hydraulic comprises twin columns inclined type combined rack and Duola's bar preload piece of free-forging hydraulic.On arbitrary free-forging hydraulic, adopt the two hollow rectangle columns and the upper and lower crossbeam of special tectonic to constitute combined rack, many high strength pull bars are placed hollow column, and pass upper and lower crossbeam, by pretightning force and the pre-clamping method of design according to regulation, make on the pull bar total length by pre-load nut to produce prefastening force, simultaneously upper and lower crossbeam and column are applied preload pressure, thereby make whole combined rack be in the stress pre-tighten state; The tilting at an angle layout of center line with the centre of form line and the press bed moving direction of two hollow rectangle columns, and with the carrier of this frame as devices such as installation hydraulic cylinder, moved cross beam, guider, travelling tables, and the stress frame that bears whole service loads, promptly constitute the body part of a free-forging hydraulic.
2) two of the combination stressed frame of twin columns inclined type multi-pull-rod prestress hollow rectangle column design, be for the rectangular cross section of hollow on total length, both ends are the structure of overhanging, and adopt four groups of cross rectangle positioning keys that upper and lower crossbeam is embedded in securely with column.From Analysis of materials mechanics as can be known, under the identical situation of cross-sectional area, make the bending resistance area inertia of material away from the hollow rectangle cross section member of neutral axis, promptly cross sectional moment of inertia is maximum, and its counter-bending energy force rate annular or open squares cross section are stronger.Even four square-section columns stack up the moment of inertia in two split column cross sections of either side, total the moment of inertia also only be have same cross-sectional area and architectural characteristic a whole column 1/4.
This hollow-core construction column is just as a natural chimney, both can directly intercept heat radiation from steel ingot or forging heat, again can be by the clearance hole or the column outer openings of sill, cold air is sucked, make to accumulate in to shed, prevented that effectively heat radiation from causing the inhomogeneous elongation of pull bar at the thermal current of column inside clearance hole from entablature.Can also prevent fully that in addition oxide skin, instrument etc. from causing damage to the pull bar surface.
Simultaneously, around every root post, provide at least 4, reached 8 orthogonal planes, for wear-resisting guide plate is installed, for moved cross beam provides a planar guide body firm, rigidity and LCS.
3) described upper and lower crossbeam is a cast structure, adopt Computerized three-dimensional finite element analysis software (FEM) Analysis of Contact Problem method, the twin columns prestressed stand is carried out the optimized integral structure design, make the distortion and the stress of frame obtain to find the solution accurately, dope the stress state and the deformation tendency thereof of the structure in the forging process, optimize the structure of stress frame, determine its physical dimension under suitable strength and rigidity, material is reasonably distributed, give full play of the potentiality of material therefor.The shape of cross section of upper and lower crossbeam being implemented the short transverse of pretension is consistent with size and pair column, simultaneously, must take special detailed design, handle and magnetic powder inspection as the clearance hole finishing tool, the circular hole that entablature is installed master cylinder adopts big round-corner transition, super allowable offset square loads in real time and detects, to avoid the stress concentration phenomenon of beam, post partial portion.
4) place the quantity of the high strength pull bar of every described hollow column, can select according to the press tonnage.Facts have proved, adopt many pull bars to be better than: available less hydraulic pre-tightening cylinder, every pull bar of pretension respectively only with a pull bar; Can arrange Duola's bar symmetrically and evenly, stress equalization by hollow column cross sectional shape; Pull rod screw root mismachining tolerance is little, and the bending stress influence of generation is less; Because cross-sectional area is little, material structure and heat treatment performance good uniformity can be given full play to the mechanical property of material; Make easy to processly, as required,, can adopt two-way nut segmentation dislocation to couple together use for the pull bar of overlength.
5) design of described pretightning force and pre-clamping method are different from the stressed frame of any press: the prestressing force design by maximum forging force and maximum allowable offset apart from design, adjust and set the prestressing force of pull bar, the pretension coefficient is 1.35, and promptly pretightning force is 1.35 times of service load; The cross sectional dimensions of upper and lower crossbeam and column contact portion is suitable, and the distortion of depth of beam direction after by compression be can not ignore, the size that is compressed member of calculating should comprise upper and lower crossbeam and column the corresponding height size; Adopt a special pre-load nut of two covers and a shared cover super-pressure pump device, according to orientation shown in Figure 4 and number order, two pull bars of the adjacent numbering on each pretension left and right pillar simultaneously, and a pretension puts in place; Adopt to become tensammetry and carry out pretension under the monitoring in real time at stress, every pull bar required pulling force difference when pretension after all pretensions are finished, reaches the pulling force of average load, the prestressing force of uniformity, and deviation is lower than 3%.
Theory and practice proves that this rack construction has higher integral rigidity, fatigue resistance, bearing capacity and security reliability.The inboard of upper and lower crossbeam no longer needs hold-down nut, behind the pretension, does not crack, and need not to repeat fastening outboard nut, and pull bar does not have wearing and tearing forever.According to Hooke's law, pull bar and should be satisfied relation shown in Figure 5 by power and deflection between the pretension member (column and beam).During work, column bears compression and bending stress, and pull bar bears tension, and the variation amplitude of its minimum and maximum tension only is 15% of a maximum load stress.Pull bar in the external same category of device is after having used more than 30 year, and the prestressing force deviation of process test pull bar is still below 10%.Can not produce the column fracture accident at machine life in cycle, therefore prolong the service life of each member, greatly reduces maintenance of equipment expense and life cycle cost.
6) the twin columns inclined type is arranged and must be utilized this effect by rights, is about to the centre of form line of two hollow rectangle columns and the tilting at an angle layout of center line of press bed moving direction.Have bigger cross sectional moment of inertia and bending rigidity than four-column type, allowable offset forging scope is big, the huge bending stress and the compression that produce in the time of can bearing eccentric load, and can reach good balance and stability.

Claims (6)

1. free-forging hydraulic twin columns inclined type prestressed stand, comprise: column, entablature, sill and pull bar, it is characterized in that: described column is a kind of hollow rectangle column (2), described hollow rectangle column (2) is two, high strength pull bar (5) places two described hollow rectangle columns (2), described entablature (4) is passed at the two ends of described pull bar (5), sill (1), between described entablature (4) and the described hollow rectangle column (2), described sill (1) adopts rectangle positioning key (3) to be embedded between described hollow rectangle column (2) respectively, pretightning force and pre-clamping method according to design code, make on described high strength pull bar (5) total length by pre-load nut (7) and to produce prefastening force, simultaneously to described entablature (1), sill (4) and described hollow rectangle column (2) apply preload pressure, thereby constitute the stressed frame of twin columns prestressing combination; The center line of the relative press bed moving direction of centre of form line of two described hollow rectangle columns (2) becomes the α angle tilting.
2. according to the described free-forging hydraulic twin columns of claim 1 inclined type prestressed stand, it is characterized in that: two described hollow rectangle columns (2) are the rectangular cross section of hollow on total length, both ends are the structure of overhanging, and the angle α of the center line of the relative press bed moving direction of its centre of form line is between 55 °~75 °.
3. according to the described free-forging hydraulic twin columns of claim 1 inclined type prestressed stand, it is characterized in that: the quantity that places the described high strength pull bar (5) of every described hollow rectangle column (2), can select 5 at least according to the press tonnage, the diameter of every described high strength pull bar (5) is between 160~φ 240mm, allowable stress 〉=the 700MPa of material, safety coefficient>2.5.
4. according to the described free-forging hydraulic twin columns of claim 1 inclined type prestressed stand, it is characterized in that: described high strength pull bar (5) is near the column wall, to the inside, the front and back side arranges that the arrangement form of described high strength pull bar (5) has two rows at least.
5. according to the described free-forging hydraulic twin columns of claim 1 inclined type prestressed stand, it is characterized in that: orthogonal wear-resisting guide plate (9) is installed around two described hollow rectangle columns (2).
6. according to the described free-forging hydraulic twin columns of claim 1 inclined type prestressed stand, it is characterized in that: described rectangle positioning key (3) has 4 groups 16, respectively between described entablature (4) and the described hollow rectangle column (2), be cross between described sill (1) and the described hollow rectangle column (2) and arrange.
CN2010201748303U 2010-04-09 2010-04-09 Double-post inclined prestressed stand for free forging hydraulic press Expired - Lifetime CN201693117U (en)

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101823114A (en) * 2010-04-09 2010-09-08 太原重工股份有限公司 Double-post inclined type multi-pull-rod prestress machine frame of free forging hydrostatic press
CN102615851A (en) * 2012-04-12 2012-08-01 太原重工股份有限公司 Prestressed stand for vertical extruder
CN104588556A (en) * 2015-01-28 2015-05-06 中国重型机械研究院股份公司 Fixing device of movable workbench oil cylinder of forging press
WO2016000526A1 (en) * 2014-06-30 2016-01-07 南京迪威尔高端制造股份有限公司 Perpendicular column beam
CN105346044A (en) * 2015-11-05 2016-02-24 大连橡胶塑料机械股份有限公司 Novel casting support of rubber twin-screw extrusion tablet press
CN111036711A (en) * 2019-12-03 2020-04-21 北京冶自欧博科技发展有限公司 Multi-roll-pitch high-rigidity high-load steel plate straightening machine

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101823114A (en) * 2010-04-09 2010-09-08 太原重工股份有限公司 Double-post inclined type multi-pull-rod prestress machine frame of free forging hydrostatic press
CN101823114B (en) * 2010-04-09 2012-05-23 太原重工股份有限公司 Double-post inclined type multi-pull-rod prestress machine frame of free forging hydrostatic press
CN102615851A (en) * 2012-04-12 2012-08-01 太原重工股份有限公司 Prestressed stand for vertical extruder
WO2016000526A1 (en) * 2014-06-30 2016-01-07 南京迪威尔高端制造股份有限公司 Perpendicular column beam
CN104588556A (en) * 2015-01-28 2015-05-06 中国重型机械研究院股份公司 Fixing device of movable workbench oil cylinder of forging press
CN105346044A (en) * 2015-11-05 2016-02-24 大连橡胶塑料机械股份有限公司 Novel casting support of rubber twin-screw extrusion tablet press
CN111036711A (en) * 2019-12-03 2020-04-21 北京冶自欧博科技发展有限公司 Multi-roll-pitch high-rigidity high-load steel plate straightening machine

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