For ordinary wire cutting machine, the wire speed is generally fixed. The adjustment of the feed rate is mainly the adjustment of the gap between the electrode wire and the workpiece. Feeding speed and erosion speed should be well coordinated during cutting and do not lag behind or track too tightly. The feed rate is adjusted mainly by adjusting the variable feed rate. Under a specific machining condition, there is only one corresponding optimal feed rate. At this time, the feeding speed of the molybdenum wire is exactly equal to the actual maximum erasing rate of the workpiece. . Under-tracking often results in open-circuit machining, virtually reducing productivity, and current instability, which can easily lead to broken wires. Over-tight tracking can easily lead to short-circuits and can also reduce the rate of material removal. Generally adjust the frequency conversion feed so that the processing current is about 0.85 times the short-circuit current (the current meter pointer is slightly shaken). It can guarantee the best working condition, that is, the frequency conversion feed speed is the most reasonable, the processing is most stable, and the cutting speed is the highest. The following table shows how to adjust the frequency conversion according to the feed state. Table Adjust the frequency conversion method according to the feed state Real-frequency status Feed state Working surface condition Cutting speed Electrode wire Frequency adjustment Tracking Slow and steady Brown low Slightly coke, fast aging Should slow down the feed rate Tracking Suddenly Uneven Not clean Easy to get deep marks Faster Easy to burn, silk White spot scars Should speed up the feed rate Poor tracking Slow and steady Slightly brown, striped low Focus color Should slightly increase the feed rate Best tracking Very stable White, smooth fast White, slow aging No need to adjust 1. The name, purpose and use of common fixtures (1) Platen clamp It is mainly used for fixing flat-shaped workpieces, and is used in pairs for slightly larger workpieces. If there is a positioning reference surface on the fixture, the fixture positioning reference surface should be calibrated in parallel with the corresponding guide rail of the worktable beforehand with a stylus or dial indicator. This is convenient when processing a batch of workpieces because the cutting of the cutting cavity is easy. It is generally based on one side of the template. When the clamps are used in pairs, the heights of the two reference surfaces must be equal. Otherwise, the cut-out cavity is not perpendicular to the end surface of the workpiece, resulting in waste products. A V-shaped reference can be machined on the fixture to hold the shaft-like workpiece. (2)Magnetic clamps use magnetic table or magnetic table holder to clamp the workpiece. It is mainly used to clamp steel workpieces. Because it absorbs the workpiece by magnetic force, it does not need the pressure plate and screws. The operation is quick and convenient. Press and change, as shown in Figure 1. Figure 1 Magnetic fixture 3. Bracing method (1) Dial indicator method As shown in Fig. 2, the dial indicator is fixed on the silk frame with a magnetic watch stand, and the work table is moved back and forth. The position of the work piece is adjusted according to the indicator value on the dial indicator until the indicator of the dial indicator is biased. The pendulum range achieves the required accuracy. Figure 2 Dial indicator alignment Figure 3 Line alignment (1) Visual inspection method As shown in Fig. 4, the cross reference line drawn at the threading hole is used to observe the relative position of the electrode wire and the reference line along the scribe direction, and the worktable is moved according to the deviation between the two. When coincident with the reference lines of the longitudinal and transverse directions respectively, the readings on the dials of the vertical and horizontal directions of the worktable determine the center position of the wire electrode. Figure 4: Adjusting wire position by visual inspection (2) Spark method As shown in Fig. 5, turn on the high frequency and the transport tube (Note: The voltage amplitude, pulse width and peak current must be minimized, and do not open the coolant). Move the table to bring the reference surface of the workpiece close to Electrode wire, in the moment of spark, note the relative coordinates of the table, and then calculate the center coordinates of the electrode wire according to the discharge gap. Although this method is simple and easy, it has poor positioning accuracy. Figure 5 spark electrode wire position adjustment 1 - Workpiece 2 - Electrode Wire 3 - Spark A molding mold for mineral water bottles, including an operating platform, wherein a lower mold is fixed on the operating platform, the lower mold is covered with an upper mold, the lower mold and the upper mold are both provided with a half-spliced mold groove, the mold groove is provided with a ring bulge and a thread bulge, the lower mold is fixed with a first cylinder block, the piston rod of the first cylinder block is fixed with a blow-molding interface that is close to the upper and lower molds, The second cylinder block is fixed on the upper mold, and a cutter is fixed on the piston rod of the second cylinder block. The cutter can cut the plastic tail after solidification, reducing the process of trimming the plastic tail after the later work, and the cutter contacts closely with the upper mold. Mold Of Mineral Water Botter,Cup Plastic Mold ,Pet Preform Mould ,Water Bottle Mold Ningbo Chenwei Machinery Technology Co.,Ltd , https://www.chenweimachinery.com
Preferably, both the lower mold and the upper mold are provided with an inner cavity, which is respectively connected with a water outlet interface and a water inlet interface, which can circulate cold water to cool the blow-molded mineral water bottle rapidly. The inlet and outlet cold water interfaces of the lower mold and the inlet and outlet cold water interfaces of the upper mold are symmetrically distributed to ensure the stability of the water inlet and outlet cold water circulation.
CNC electric spark wire cutting processing technology and tooling
First, CNC electric wire cutting process The line cutting process is mainly a reasonable choice of electrical processing parameters and mechanical parameters. Electrical processing parameters include pulse width and frequency, discharge gap, peak current, and the like. Mechanical parameters include feed rate and wire speed. Should comprehensively consider the impact of various parameters on the processing, reasonable selection of process parameters, in the premise of ensuring the quality of the workpiece processing, improve productivity and reduce production costs. 1. The choice of electrical processing parameters The correct choice of pulse power processing parameters can improve the processing index and processing stability. When roughing, a larger processing current and a large pulse energy should be used to obtain a higher material removal rate (ie, processing productivity). In the finishing process, a smaller processing current and a smaller single pulse energy should be used to obtain a lower surface roughness of the machined workpiece. The processing current refers to the average value of the current passing through the processing area. The single pulse energy is mainly determined by the pulse width, peak current, and processing amplitude voltage. The pulse width refers to the duration of the pulse current when the pulse is discharged. The peak current refers to the peak value of the pulse current during the discharge processing. The processing amplitude voltage refers to the peak value of the pulse voltage during the discharge machining. The following reference examples are available for use: (1) Finishing: Pulse width selects the minimum gear, voltage amplitude selects low gear, amplitude voltage is about 75V, connects one to two power tubes, adjusts the frequency conversion potentiometer, the machining current is controlled at 0.8~1.2A, and the machining surface Roughness Ra≤2.5um. (2) Maximum material removal rate processing: Pulse width is selected from 4th to 5th gears, voltage amplitude is selected from “high†value, amplitude voltage is about 100V, power tube is all turned on, frequency potentiometer is adjusted, and processing current is controlled at 4~ 4.5A, the removal rate (processing rate) of about 100 mm2/min can be obtained. (The material thickness is about 40~60mm). (3) Large-thickness workpiece processing (>300mm): amplitude voltage hits "high" gear, pulse width selects five to six gears, power tube opens 4~5, machining current is controlled at 2.5~3A, material removal rate> 30mm2/min. (4) Large-thickness workpiece processing (60~100mm): amplitude voltage hits high grade, pulse width selects five levels, power tube opens four or so, processing current is adjusted to 2.5~3A, material removal rate is 50~60mm2/min . (5) Thin workpiece machining: Amplitude voltage is selected as low gear, pulse width is selected as the first or second gear, power tube is opened 2~3, and the processing current is adjusted to about 1A. Note that the pulse power output must be turned off to change the electrical parameters of the processing. (Except for adjusting the interval potentiometer RP1), the processing power standard should not be changed during the processing, otherwise it will cause the surface roughness of the processing is not the same. 2. Selection of mechanical parameters