01.Preparations for boot

The machine tool in each boot or the machine tool according to the emergency stop reset, the first back to the machine reference zero (that is, back to zero), so that the machine tool for its subsequent operation has a reference position.

02.Clamp workpiece

Before the workpiece clamping to clean the surface, can not stick with oil, iron and dust, and file (or stone) to remove the surface of the workpiece burr.

The clamping equihigh-speed rail must be ground by the grinder to smooth the surface, so that it is smooth and smooth. Code iron, nut must be strong, can reliably clamp the workpiece, for some difficult to clamp small workpiece can be directly clamped on the tiger; The machine tool table should be clean and clean, without iron filings, dust, oil; The pad is generally placed in the four corners of the workpiece, and the span of the workpiece is too large to be added in the middle of the high pad.

According to the size of the drawing, use the pull ruler to check whether the length, width and height of the workpiece are qualified.

When clamping the workpiece, according to the way of clamping and placing in the programming work instruction, we should consider to avoid the processing parts and the situation that the tool head may encounter the fixture in the processing.

After the workpiece is placed on the pad, it is necessary to pull the table on the workpiece datum according to the requirements of the drawing. For the workpiece that has been ground on six sides, it is necessary to check whether its verticality is qualified.

The workpiece must be tightened after pulling the table, in order to prevent the clamping is not firm and the workpiece in the processing of the phenomenon of displacement; Pull the table again to make sure the error is not out of tolerance after clamping.

03.Number of workpiece touches

The clamping workpiece can be used to touch the number of the head for the reference zero processing, touch the number of the head available photoelectric and mechanical two. The methods are divided into two kinds: the number of medium collision and the number of unilateral collision. The steps of the number of medium collision are as follows:

Photoelectric static, mechanical speed 450~600rpm. In the middle of the touch number manually move the X axis of the worktable, so that the touch number head touches one side of the workpiece, when the touch number head just touches the workpiece and the red light is on, the relative coordinate value of this point is set to zero; Then manually move the X axis of the worktable to touch the head of the other side of the workpiece, when the head just touched the workpiece, write down the relative coordinates at this time.

According to its relative value minus the diameter of the number of head (that is, the length of the workpiece), check whether the length of the workpiece conforms to the drawing requirements.

Divide the relative coordinate number by 2 to get the intermediate value of the X-axis of the workpiece. Then move the workbench to the intermediate value of the X-axis. Set the relative coordinate value of the X-axis of this point to zero, which is the zero position of the X-axis of the workpiece.

Carefully record the mechanical coordinate value of the zero position on the X-axis of the workpiece in one of G54~G59, and let the machine determine the zero position on the X-axis of the workpiece. Again, carefully check the correctness of the data. The procedure of setting the zero position of the workpiece on the Y axis is the same as that on the X axis.

04.Get all the knives ready

According to the tool data in the programming work instruction, change the tool to be processed, and let the tool touch the height gauge placed on the datum plane. When the red light of the gauge is on, the relative coordinate value of this point is set to zero.

Move the tool to a safe place, manually move the tool down 50mm, and set the relative coordinate of this point to zero again, which is the zero of the Z axis.

Record the mechanical coordinate Z value of this point in one of G54~G59. This completes the zero setting of X, Y and Z axes of the workpiece. Again, carefully check the correctness of the data.

Unilateral touch number is also according to the above method to touch the workpiece X, Y axis side, the point of X, Y axis relative coordinate value offset the radius of the head is X, Y axis zero, finally put a point X, Y axis mechanical sitting mark in one of G54~G59. Again, carefully check the correctness of the data.

Check the correctness of the zero point, move the X and Y axes to the edge of the workpiece, according to the size of the workpiece, visual inspection of the correctness of the zero point.

Copy the program files to the computer according to the file path of the programming work instruction.

05.Setting of machining parameters

Setting of spindle speed in processing:

N = 1000 x V/(3.14 x D)

N: spindle speed (RPM /min)

V: Cutting speed (m/min)

D: Tool Diameter (mm)

Processing feed speed setting: F=N×M× FN

F: Feed speed (mm/min)

M: Number of cutting edges

Fn: Cutting amount of tool (mm/ revolution)

Setting of cutting amount of each edge: FN =Z× FZ

Z: Number of cutting edges

Fz: Cutting amount per tool edge (mm/ RPM)

06.Boot-on processing

Each program must be started by carefully checking whether the tool used is the one specified in the programming instruction book. Began to make feed processing speed to the minimum, single section, rapid positioning, falling knife, feed must concentrate, when there is something wrong with the hand should be put on the stop button to immediately stop, watch tool motion direction to ensure the safety of feed, then slowly increase the feed rate to the right, at the same time to the cutting tool and workpiece cooling fluid or air cooling.

Don’t be too far away from the control panel when opening rough machining. Stop the machine in time for inspection if there is any abnormal phenomenon.

After opening the rough, pull the table again to determine that the workpiece is not loose. If so, recalibrate and touch the number.

In the process of processing continuously optimize the processing parameters, to achieve the best processing effect.

Because this process is a key process, the workpiece should be measured after the completion of the processing of the main size of the value is consistent with the requirements of the drawing, if there is any problem, immediately inform the team leader or programmer on duty to check and solve, after self-inspection qualified, can be removed, and must be sent to the inspector for special inspection.

Processing type:

Hole processing: before drilling on the machining center, we must first use the center drill to locate, and then drill with 0.5~2mm smaller than the size of the drawing, and finally finish with the appropriate bit.

Reaming processing: the workpiece for reaming processing is also to first use the center drill positioning, and then use smaller than the drawing size of 0.5~0.3mm drill hole, and finally reamer reaming, reaming processing pay attention to control the spindle speed in 70~180rpm/min.

Boring processing: the workpiece boring processing to first use the central drill positioning, and then use the drawing size smaller than 1~2mm drill hole, and then use rough boring cutter (or milling cutter) processing to only left a side of 0.3mm or so processing allowance, and finally with pre-adjusted size of fine boring cutter for fine boring, the last time fine boring allowance can not be less than 0.1mm.

Direct numerical control (DNC) operation: before DNC numerical control processing to clamp the workpiece, set the zero position, set the parameters. Open the processing program to be transmitted in the computer for inspection, and then let the computer into DNC state, and enter the file name of the correct processing program. Press the Tape key and program start key on the machine tool, then the word LSK will appear flashing in the machine tool controller. DNC data transfer processing can be performed by pressing the enter keyboard on the computer.

07 Self-test content and scope

The processor must see the content of the process card clearly before processing, and clearly know the parts, shapes, sizes of the drawings to be processed, and know the processing content of the next process.

Before clamping the workpiece, the size of the blank should be measured to see if it conforms to the requirements of the drawing. When clamping the workpiece, the placement must be carefully checked to see if it conforms to the programming instruction.

After the completion of rough machining, self-inspection should be carried out in time to adjust the data with errors in time. The main content of self – inspection is the location and size of the processing parts. Such as: whether the workpiece is loose; Whether the workpiece is correctly divided into the center; Whether the size from the machining part to the reference edge (reference point) meets the requirements of the drawing; Position dimensions of each machining part. After checking the position and size, the shape ruler of rough machining should be measured (except arc).

Finishing is carried out only after rough machining is self-checked. After finishing, workers should self-check the shape and size of the processing parts: check the basic length and width of the vertical plane of the processing parts; Measure the dimension of the base point marked on the drawing for the machining part of the inclined surface.

After completing the self-inspection of the workpiece and confirming that it conforms to the drawing and process requirements, the worker can disassemble the workpiece and send it to the inspector for special inspection.