CN113500258A - Die oil groove machining method based on electric spark process - Google Patents
Die oil groove machining method based on electric spark process Download PDFInfo
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- CN113500258A CN113500258A CN202110880043.3A CN202110880043A CN113500258A CN 113500258 A CN113500258 A CN 113500258A CN 202110880043 A CN202110880043 A CN 202110880043A CN 113500258 A CN113500258 A CN 113500258A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23H—WORKING OF METAL BY THE ACTION OF A HIGH CONCENTRATION OF ELECTRIC CURRENT ON A WORKPIECE USING AN ELECTRODE WHICH TAKES THE PLACE OF A TOOL; SUCH WORKING COMBINED WITH OTHER FORMS OF WORKING OF METAL
- B23H1/00—Electrical discharge machining, i.e. removing metal with a series of rapidly recurring electrical discharges between an electrode and a workpiece in the presence of a fluid dielectric
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23H—WORKING OF METAL BY THE ACTION OF A HIGH CONCENTRATION OF ELECTRIC CURRENT ON A WORKPIECE USING AN ELECTRODE WHICH TAKES THE PLACE OF A TOOL; SUCH WORKING COMBINED WITH OTHER FORMS OF WORKING OF METAL
- B23H11/00—Auxiliary apparatus or details, not otherwise provided for
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- Electrical Discharge Machining, Electrochemical Machining, And Combined Machining (AREA)
Abstract
The invention discloses a die oil groove processing method based on an electric spark process, which comprises the following steps of: s1: pretreating the mold, removing burrs on the surface of the mold, cleaning a magnetic table, and determining the machining size and the machining direction of an oil groove of the mold; s2: clamping the mold, namely placing the pretreated mold into a processing tank, fixing the mold through a clamp, correcting the clamping position of the mold, and installing a filter, a pulse power supply and a working liquid pump; s3: the mixed working fluid is injected into the processing tank. The mixed liquid of the invention mixes kerosene and aluminum powder, and the added aluminum powder causes weak discharge between the aluminum powder and the powder in the working liquid, and the single pulse discharge energy is dispersed on the whole discharge channel and the processing surface, thereby generating discharge dispersion effect, reducing the release amount of each discharge pad, reducing the area and depth of electric corrosion, ensuring the flatness of the processing surface, and improving the processing precision of the oil groove of the mould.
Description
Technical Field
The invention relates to oil groove machining, in particular to a die oil groove machining method based on an electric spark process, and belongs to the technical field of dies.
Background
Electrical discharge machining is a machining process that uses a discharge electrode (EDM electrode) having a specific geometry to burn the geometry of the electrode onto a metal (conductive) part. The electric spark machining process is commonly used for the production of blanking dies and casting dies, and a method for machining the size of a material by using an erosion phenomenon generated during spark discharge is called as electric spark machining, wherein the electric spark machining is spark discharge in a liquid medium within a lower voltage range and is mainly completed by a machinery factory, and the electric spark is self-excited discharge and is characterized in that: the high voltage is applied between two electrodes of spark discharge before discharge, when the two electrodes approach, the medium between them is broken down, then the spark discharge is generated, along with the breakdown process, the resistance between the two electrodes is sharply reduced, the voltage between the two electrodes is also sharply reduced, the spark channel must be extinguished in time after maintaining a short time (usually 10-7-10-3s), just the 'cold electrode' characteristic of spark discharge can be maintained (namely the heat energy converted by the channel energy is not transmitted to the depth of the electrode), the channel energy acts on a very small range, and the electrode can be partially corroded due to the action of the channel energy.
At present, when an electric spark process is used for machining an oil groove, the machining die is easy to cause that the surface of the machined oil groove is thick, and in addition, in the process of a pulse electrode, an electric corrosion area is large, so that the precision of the machined oil groove is easily influenced.
Disclosure of Invention
The invention aims to provide a die oil groove machining method based on an electric spark process, so as to solve the problems in the background technology.
In order to achieve the purpose, the invention provides the following technical scheme: the method comprises the following steps:
s1: pretreating the mold, removing burrs on the surface of the mold, cleaning a magnetic table, and determining the machining size and the machining direction of an oil groove of the mold;
s2: clamping the mold, namely placing the pretreated mold into a processing tank, fixing the mold through a clamp, correcting the clamping position of the mold, and installing a filter, a pulse power supply and a working liquid pump;
s3: injecting mixed working fluid into the processing tank until the mixed working fluid completely submerges the processing mold;
s4: the method comprises the following steps of configuring machining parameters, setting current, setting discharge amplitude, setting pause, setting discharge gap voltage, setting speed, setting discharge machining time, setting polarity and setting a pulse electrode walking route;
s5: processing an oil groove, opening a pulse electrode, a filter and a working liquid pump, forming a discharge channel between the pulse electrode and a mould, enabling a material to be molten by instant high temperature generated in a discharge area, carrying out walking processing on the pulse electrode according to a set walking route, and carrying out filtering and backflow processing on the working liquid through the filter and the working liquid pump in the processing process;
and S6, detecting and packaging oil groove parameters.
As a preferred technical solution of the present invention, the mixed working fluid may be: kerosene: aluminum powder is mixed solution with the ratio of 99.6:0.4, deionized water: mixed liquor with nickel of 99.3:0.7 ratio, mineral oil: the mixture ratio of silicon carbide is 99.7: 0.3.
In a preferred embodiment of the present invention, the mold clamping position is determined by determining a machining coordinate of the electrode reference center from a distance between the electrode reference center and the machining mold reference center or by determining a machining position from a distance between the electrode reference center and one side of the machining mold.
As a preferred technical solution of the present invention, the setting of the current, the setting of the discharge amplitude, and the setting of the pause are specifically set as follows:
setting the current: the method comprises the steps that the current set value is larger, the machining speed is higher, the surface of the oil groove is rough, the current set value is smaller, the machining speed is slower, and the surface of the oil groove is finer;
setting a discharge amplitude: controlling the discharge frequency, wherein the larger the discharge amplitude set value is, the lower the discharge frequency is, the smaller the electrode consumption is, the smaller the discharge amplitude set value is, the higher the discharge frequency is, and the electrode consumption is large;
setting of rest: the smaller the set value is, the longer the discharge time is, the larger the average current is, the higher the discharge efficiency is, and the faster the machining speed is, but the more likely to cause the defective slag discharge, and the larger the set value is, the shorter the discharge time is, the smaller the average current is, the lower the discharge efficiency is, and the easier the slag discharge is.
As a preferred technical solution of the present invention, the setting of the discharge gap voltage, the setting of the speed, the setting of the electric discharge machining time, and the setting of the polarity are specifically set as follows:
discharge gap voltage setting: the discharge gap voltage is generally adjusted to 50-100v, small current or large area and deep hole processing is selected, the discharge gap voltage is increased, and the slag discharge condition is improved;
setting the speed: for adjusting the feeding speed and the stability of discharging and the feeding speed of the spindle during discharging so as to achieve a stable discharging effect;
setting of electric discharge machining time: controlling the electric discharge machining time according to the depth of the oil groove;
setting the polarity: the polarity of the electrode was set as positive, and the working mold was set as negative.
As a preferred technical solution of the present invention, the setting of the pulse electrode walking route includes the following steps:
the first step is as follows: determining the specific specification of the oil groove of the processing die and the processing direction of the processing route;
the second step is that: establishing a pulse electrode motion model according to a processing route and a processing direction of a processing die;
the third step: and controlling the motion direction of the pulse electrode according to the motion model of the pulse motor.
As a preferred embodiment of the present invention, the detailed parameters of the filter and the detailed parameters of the working fluid pump in step S5 are:
the flow requirement of the filter is 9.5-12m3The interface of the filter is 2, and the filtering progress of the filter is 0.3 mu m;
the flow requirement of the working fluid pump is 10-12m3The power of the working liquid pump is 35-75kW, and the rotating speed of the working liquid pump is 2400-2900 r/min.
As a preferred embodiment of the present invention, the step S6 of detecting the oil groove parameter includes: and detecting the flatness of the machining die oil groove and the shape and specification of the machining die oil groove, determining the error range, and packaging.
Compared with the prior art, the invention has the beneficial effects that:
1. in the method for processing the die oil groove based on the electric spark process, the mixed liquid is mixed with the kerosene and the aluminum powder, and the added aluminum powder enables weak discharge to be generated between the aluminum powder and the powder in the working liquid.
2. According to the die oil groove machining method based on the electric spark process, the efficiency and the precision of machining the die oil groove are effectively guaranteed through the setting of the current, the setting of the discharge amplitude, the setting of the pause and the setting of the discharge gap voltage in the machining process.
Drawings
FIG. 1 is a block flow diagram of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1, the present invention provides a technical scheme of a method for machining an oil groove of a mold based on an electric spark process:
example 1: die oil groove machining method based on electric spark process
S1: pretreating the mold, removing burrs on the surface of the mold, cleaning a magnetic table, and determining the machining size and the machining direction of an oil groove of the mold;
s2: clamping the die, namely placing the pretreated die into a processing tank, fixing the die by a clamp, correcting the clamping position of the die, installing a filter, a pulse power supply and a working liquid pump, determining the clamping position of the die, and determining a processing coordinate by the distance between an electrode reference center and a processing die reference center or determining a processing position by the distance between the electrode reference center and a processing die single side;
s3: mixed working solution is injected into the processing tank until the mixed working solution completely submerges the processing mold, and the mixed working solution is: kerosene: aluminum powder is mixed solution with the proportion of 99.6: 0.4;
s4: the method comprises the following steps of configuring machining parameters, setting current, setting discharge amplitude, setting pause, setting discharge gap voltage, setting speed, setting discharge machining time, setting polarity and setting a pulse electrode walking route;
s5: processing an oil groove, opening a pulse electrode, a filter and a working liquid pump, forming a discharge channel between the pulse electrode and a mould, enabling a material to be melted by instant high temperature generated in a discharge area, carrying out walking processing on the pulse electrode according to a set walking route, filtering and refluxing the working liquid by the filter and the working liquid pump in the processing process, wherein the flow requirement of the filter is 9.5-12m3The interface of the filter is 2, the filtering progress of the filter is 0.3 mu m, and the flow requirement of the working liquid pump is 10-12m3The power of the working liquid pump is 35-75kW, and the rotating speed of the working liquid pump is 2400-;
s6, detecting and packaging the oil groove parameters, wherein the oil groove parameters are detected by flatness of the machining die oil groove, shape and specification of the machining die oil groove, and packaging is carried out within a determined error range.
The current setting, the discharge amplitude setting and the pause setting are specifically set as follows:
setting the current: the method comprises the steps that the current set value is larger, the machining speed is higher, the surface of the oil groove is rough, the current set value is smaller, the machining speed is slower, and the surface of the oil groove is finer;
setting a discharge amplitude: controlling the discharge frequency, wherein the larger the discharge amplitude set value is, the lower the discharge frequency is, the smaller the electrode consumption is, the smaller the discharge amplitude set value is, the higher the discharge frequency is, and the electrode consumption is large;
setting of rest: the smaller the set value is, the longer the discharge time is, the larger the average current is, the higher the discharge efficiency is, and the faster the machining speed is, but the more likely to cause the defective slag discharge, and the larger the set value is, the shorter the discharge time is, the smaller the average current is, the lower the discharge efficiency is, and the easier the slag discharge is.
The discharge gap voltage setting, speed setting, discharge machining time setting and polarity setting are specifically set as follows:
discharge gap voltage setting: the discharge gap voltage is generally adjusted to 50-100v, small current or large area and deep hole processing is selected, the discharge gap voltage is increased, and the slag discharge condition is improved;
setting the speed: for adjusting the feeding speed and the stability of discharging and the feeding speed of the spindle during discharging so as to achieve a stable discharging effect;
setting of electric discharge machining time: controlling the electric discharge machining time according to the depth of the oil groove;
setting the polarity: the polarity of the electrode was set as positive, and the working mold was set as negative.
The pulse electrode walking route setting method comprises the following steps:
the first step is as follows: determining the specific specification of the oil groove of the processing die and the processing direction of the processing route;
the second step is that: establishing a pulse electrode motion model according to a processing route and a processing direction of a processing die;
the third step: and controlling the motion direction of the pulse electrode according to the motion model of the pulse motor.
In the embodiment, the mixed liquid is mixed with the kerosene and the aluminum powder, and the added aluminum powder causes weak discharge between the aluminum powder and the powder in the working liquid.
Example 2: die oil groove machining method based on electric spark process
S1: pretreating the mold, removing burrs on the surface of the mold, cleaning a magnetic table, and determining the machining size and the machining direction of an oil groove of the mold;
s2: clamping the die, namely placing the pretreated die into a processing tank, fixing the die by a clamp, correcting the clamping position of the die, installing a filter, a pulse power supply and a working liquid pump, determining the clamping position of the die, and determining a processing coordinate by the distance between an electrode reference center and a processing die reference center or determining a processing position by the distance between the electrode reference center and a processing die single side;
s3: mixed working solution is injected into the processing tank until the mixed working solution completely submerges the processing mold, and the mixed working solution is: deionized water: mixed solution with the proportion of nickel being 99.3: 0.7;
s4: the method comprises the following steps of configuring machining parameters, setting current, setting discharge amplitude, setting pause, setting discharge gap voltage, setting speed, setting discharge machining time, setting polarity and setting a pulse electrode walking route;
s5: processing an oil groove, opening a pulse electrode, a filter and a working liquid pump, forming a discharge channel between the pulse electrode and a mould, enabling a material to be melted by instant high temperature generated in a discharge area, carrying out walking processing on the pulse electrode according to a set walking route, filtering and refluxing the working liquid by the filter and the working liquid pump in the processing process, wherein the flow requirement of the filter is 9.5-12m3The interface of the filter is 2, the filtering progress of the filter is 0.3 mu m, and the flow requirement of the working liquid pump is 10-12m3The power of the working liquid pump is 35-75kW, and the rotating speed of the working liquid pump is 2400-;
s6, detecting and packaging the oil groove parameters, wherein the oil groove parameters are detected by flatness of the machining die oil groove, shape and specification of the machining die oil groove, and packaging is carried out within a determined error range.
In the embodiment, the mixed solution is mixed with nickel through deionized water, and through the added nickel, the electric corrosion product generated in the discharging process has higher fluidity by widening the discharging channel, so that the accumulation of the electric corrosion product is avoided to a great extent, the machining process is more stable, the influence of the electric corrosion product on discharging is obviously reduced along with the increase of the discharging gap and the existence of powder particles, and the occurrence of concentrated discharging phenomenon is avoided to the great extent.
In the description of the present invention, it is to be understood that the indicated orientations or positional relationships are based on the orientations or positional relationships shown in the drawings and are only for convenience in describing the present invention and simplifying the description, but are not intended to indicate or imply that the indicated devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are not to be construed as limiting the present invention.
In the present invention, unless otherwise explicitly specified or limited, for example, it may be fixedly attached, detachably attached, or integrated; can be mechanically or electrically connected; the terms may be directly connected or indirectly connected through an intermediate, and may be communication between two elements or interaction relationship between two elements, unless otherwise specifically limited, and the specific meaning of the terms in the present invention will be understood by those skilled in the art according to specific situations.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (8)
1. A die oil groove processing method based on an electric spark process is characterized by comprising the following steps:
s1: pretreating the mold, removing burrs on the surface of the mold, cleaning a magnetic table, and determining the machining size and the machining direction of an oil groove of the mold;
s2: clamping the mold, namely placing the pretreated mold into a processing tank, fixing the mold through a clamp, correcting the clamping position of the mold, and installing a filter, a pulse power supply and a working liquid pump;
s3: injecting mixed working fluid into the processing tank until the mixed working fluid completely submerges the processing mold;
s4: the method comprises the following steps of configuring machining parameters, setting current, setting discharge amplitude, setting pause, setting discharge gap voltage, setting speed, setting discharge machining time, setting polarity and setting a pulse electrode walking route;
s5: processing an oil groove, opening a pulse electrode, a filter and a working liquid pump, forming a discharge channel between the pulse electrode and a mould, enabling a material to be molten by instant high temperature generated in a discharge area, carrying out walking processing on the pulse electrode according to a set walking route, and carrying out filtering and backflow processing on the working liquid through the filter and the working liquid pump in the processing process;
and S6, detecting and packaging oil groove parameters.
2. The die oil groove machining method based on the electric spark process as claimed in claim 1, wherein the machining method comprises the following steps: the mixed working solution can be: kerosene: aluminum powder is mixed solution with the ratio of 99.6:0.4, deionized water: mixed liquor with nickel of 99.3:0.7 ratio, mineral oil: the mixture ratio of silicon carbide is 99.7: 0.3.
3. The die oil groove machining method based on the electric spark process as claimed in claim 1, wherein the machining method comprises the following steps: and determining the clamping position of the die, namely determining the machining coordinate of the die through the distance between the electrode reference center and the machining die reference center or determining the machining position through the distance between the electrode reference center and the single side of the machining die.
4. The die oil groove machining method based on the electric spark process as claimed in claim 1, wherein the machining method comprises the following steps: the current setting, the discharge amplitude setting and the pause setting are specifically set as follows:
setting the current: the method comprises the steps that the current set value is larger, the machining speed is higher, the surface of the oil groove is rough, the current set value is smaller, the machining speed is slower, and the surface of the oil groove is finer;
setting a discharge amplitude: controlling the discharge frequency, wherein the larger the discharge amplitude set value is, the lower the discharge frequency is, the smaller the electrode consumption is, the smaller the discharge amplitude set value is, the higher the discharge frequency is, and the electrode consumption is large;
setting of rest: the smaller the set value is, the longer the discharge time is, the larger the average current is, the higher the discharge efficiency is, and the faster the machining speed is, but the more likely to cause the defective slag discharge, and the larger the set value is, the shorter the discharge time is, the smaller the average current is, the lower the discharge efficiency is, and the easier the slag discharge is.
5. The die oil groove machining method based on the electric spark process as claimed in claim 1, wherein the machining method comprises the following steps: the discharge gap voltage setting, speed setting, discharge machining time setting and polarity setting are specifically set as follows:
discharge gap voltage setting: the discharge gap voltage is generally adjusted to 50-100v, small current or large area and deep hole processing is selected, the discharge gap voltage is increased, and the slag discharge condition is improved;
setting the speed: for adjusting the feeding speed and the stability of discharging and the feeding speed of the spindle during discharging so as to achieve a stable discharging effect;
setting of electric discharge machining time: controlling the electric discharge machining time according to the depth of the oil groove;
setting the polarity: the polarity of the electrode was set as positive, and the working mold was set as negative.
6. The die oil groove machining method based on the electric spark process as claimed in claim 1, wherein the machining method comprises the following steps: the pulse electrode walking route setting method comprises the following steps:
the first step is as follows: determining the specific specification of the oil groove of the processing die and the processing direction of the processing route;
the second step is that: establishing a pulse electrode motion model according to a processing route and a processing direction of a processing die;
the third step: and controlling the motion direction of the pulse electrode according to the motion model of the pulse motor.
7. The die oil groove machining method based on the electric spark process as claimed in claim 1, wherein the machining method comprises the following steps: the detailed parameters of the filter and the detailed parameters of the working fluid pump in step S5 are as follows:
the flow requirement of the filter is 9.5-12m3The interface of the filter is 2, and the filtering progress of the filter is 0.3 mu m;
the flow requirement of the working fluid pump is 10-12m3The power of the working liquid pump is 35-75kW, and the rotating speed of the working liquid pump is 2400-2900 r/min.
8. The die oil groove machining method based on the electric spark process as claimed in claim 1, wherein the machining method comprises the following steps: the step S6 of detecting the oil groove parameter includes: and detecting the flatness of the machining die oil groove and the shape and specification of the machining die oil groove, determining the error range, and packaging.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202110880043.3A CN113500258A (en) | 2021-08-02 | 2021-08-02 | Die oil groove machining method based on electric spark process |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202110880043.3A CN113500258A (en) | 2021-08-02 | 2021-08-02 | Die oil groove machining method based on electric spark process |
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| CN113500258A true CN113500258A (en) | 2021-10-15 |
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| CN202110880043.3A Withdrawn CN113500258A (en) | 2021-08-02 | 2021-08-02 | Die oil groove machining method based on electric spark process |
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