Craft of oscillatory effectiveness for a given period of time is in forging press bed is big heavy-duty solder the application in structural member
- source:EAGLEBURGER CNC Machining
10 thousand yuan. Visible, large structural member handles the effect with law of oscillatory effectiveness for a given period of time apparent. Program of technology of 2 oscillatory effectiveness for a given period of time 2.
1 cut vibration theoretic tell by brace up workpiece wants to move stress only below any oscillatory frequency enough the result that can achieve leveling remains stress and stable dimension greatly. But produce bigger vibration to can arouse large component part with the smallest energy, we place vibrator be in in the wave crest that is far from fulcrum, make slant of heart annulus rotate the face is parallel the plane at fulcrum, make below 2 faces on workpiece are made thereby show the resonance that cuts motion. The fillet weld of the welding line that goes up to vertical plane and fluctuation plane and each vertical plane can produce this kind of vibration bigger move stress, acceleration sensor should be put in the edge to grow bigger at the same time, in order to obtain louder oscillatory signal, specific decorate 1a seeing a picture. 2.
Many bits of vibration below state of 2 fixed fulcrum because work is very serious, the lightest also have 80t, and the ability removing condole of spot drive a vehicle has 30t only, reason can use jack to carry workpiece on the head only. When the top rises, want to fill up stretch balata space block in branch office. To make workpiece can be obtained everywhere enough move stress greatly, used secure the plan that supports many bits of Shi Zhen. The installation position of this plan vibrator is used " perpendicular bisector law " , make a triangle for acme with 3 fulcrum center namely, triangle the fixed area that the nodical position of the perpendicular bisector of 3 edges and brim line is vibrator namely (graph 1b) . Resistance of vibration of this kind of oscillatory model is little, obtain the resonance with bigger amplitude easily. To obtain first-rate vibration result, can set 3~4 to every workpiece stimulate brace up the dot undertakes vibration. The size that presses workpiece configuration, weight, leftover stress and distributing different, every are stimulated brace up the oscillatory time of the dot is 10~20min. 2.
Vibration of 3 much frequency is in same kind stimulate brace up below condition (fulcrum and stimulate a dot not to change positional) , can use different frequency to undertake vibration. If vibrator power is great, still can use force vibration. Because after wavelengh changes vibration, this kind of plan moves the peak value area of stress to also produce change, so every change frequency to should change the position of acceleration sensor. 3 craft are carried out and data measures Nextpage graph 2a, B, C to be slide block, base respectively, on the fulcrum of crossbeam, stimulate what dot and leftover stress measure a place to arrange a plan. Every workpiece sets 6 to measure an area, every measure an area at 2 o'clock, brace up before a bit, brace up hind a bit, the distance this 2 o'clock is 50~100mm, see a picture 3. Use blind aperture method, meet an emergency piece resistance is 120 Ω , of sensitivity coefficient K=2 special 3 structures undertake metrical, its get diameter and deepness to be 2mm. Resonance frequency decides with sweep law first when vibration, be in next different stimulate brace up the dot undertakes vibration a few times, mix to Zhen Pin, amplitude at the same time move stress to have observation. The oscillatory parameter of 3 workpiece model sees a table 1, brace up before, brace up hind computation of leftover stress test sees a table as a result 2. Graph 4a, B, C reacted directly brace up before, brace up hind circumstance of leftover stress change. 4 data are analysed (1) expresses 1 data to make clear, the vibration of 3 workpiece all obtained crucial resonance frequency. When because be in,having oscillatory effectiveness for a given period of time to the object, object itself also is an oscillatory body, it and fixed bearing dot formed an oscillatory system, although base is heavy, but its span is very long, reason resonance frequency is low. Moving stress is the crucial parameter in oscillatory effectiveness for a given period of time, its size affects the result of oscillatory effectiveness for a given period of time directly. The measurement that uses stress and the far and near that are apart from vibrator are concerned, effect of better to obtain oscillatory effectiveness for a given period of time, vibrator should change a few positions undertake vibration. Measure from each azimuth when vibration move stress value to all be more than 10MPa, satisfied theoretic numeric requirement, achieved result of expectant oscillatory effectiveness for a given period of time. (Of stability of dimension of 2) influence weldment is the size of leftover stress numerical value not just, still have the uniformity of leftover stress. Oscillatory effectiveness for a given period of time can eliminate stress not only, and can eliminate stress peak value, make stress is changed equably. From the graph 4a, B, C can see, the leftover stress of 3 workpiece after passing oscillatory effectiveness for a given period of time got leveling apparently. Additional, because use, is blind aperture law, the stress that is measured to nod so lies why to be planted condition is inestimable. From the graph 4 in can see, show the aspect that pull stress or controls stress to sufferred power position to produce change after vibration formerly, the stress after this shows oscillatory effectiveness for a given period of time further distributings really forward favorable position changes. The leftover stress that there are 4 to nod in the dot is in 160MPa above, still one is 229MPa. And brace up hind the greatest leftover stress of 3 workpiece is in 160MPa above, still have the dot is 229MPa, and brace up hind the greatest leftover stress of 3 workpiece is 145MPa, add its and change of design work stress also be less than 240MPa. Visible, the workpiece after oscillatory effectiveness for a given period of time will work in stretch interval, and won't appear lose firm status, satisfied workpiece to enlist in army the requirement of dimension stability. 5 conclusion (if 1) eliminates the goal of stress it is to raise workpiece to enlist in army of dimension stability, can replace hot effectiveness for a given period of time with oscillatory effectiveness for a given period of time, can obtain obvious economic benefits. (2) counterpoise tigidity solders structure, outside dividing the vibrator that used high-power, still need to use technology of compound vibration effectiveness for a given period of time, if cut vibration, for many times many bits of vibration and the craft such as many frequency vibration. Want technology only the design is reasonable, can achieve the result that eliminates stress. (Effect of 3) oscillatory effectiveness for a given period of time should with stress overall average drops highest and leftover stress and design work after rate and vibration stress alternate adds a value to whether exceed material yield point to undertake double differentiate. The 3 workpiece stress of this second vibration drops rate achieve 30%~40% , satisfied use requirement. CNC Milling CNC Machining