How to turn a quadratic curve thread, how to turn a double wire trapezoidal thread

If you really want to turn, the workpiece of the quadratic curve profile must have a certain outer diameter, which must be large enough, that is to say, there must be a linear speed required for turning (the turning thread speed can not be too fast, because of the problem of acceleration, there will be a distorted part, and it takes time for the acceleration to reach a certain value from 0).You can try the generative approach. Or with the help of some software programming.

If it is an equal pitch thread in a certain shaft direction, it is okay, that is, use G01 to do the thread, you can only do a small pitch thread, and the size of the thread on the X-axis of the workpiece cannot be changed too much, and the equal angular velocity G97, G01 is followed by a large knife, note that this is an approximate practice, and it is impossible to be completely standard.

Ordinary CNC lathes don't seem to be able to come out! To process on a turning center or a four-axis linkage machining center, computer programming is required, and manual programming is not good!

If the thread profile symmetry line is perpendicular to the axis of the part, the so-called "quadratic curve profile external turning thread" is essentially to let the tool tip follow the equidistant curve of the quadratic curve according to the thread depth, but the longitudinal speed of the tool holder is the same as that of the ordinary thread of the car, and it should be strictly locked according to the relationship between the pitch and the spindle speed (or directly hitch the wheel car).

If it is a turning arc surface worm, the tool should rotate the center line of the arc surface at the same time, if the tool holder of your CNC lathe has a programmable rotation function, it can be programmed, if not, you need to modify the mechanical structure of the rotary tool holder.

Summary. Hello, Glad to serve you. (1) Management of the bottom hole.

A tap is a tool that cuts against the bottom hole.

If the bottom hole accuracy is poor, the thread accuracy will also deteriorate, and it will also have a greater impact on the life of the tap.

Hello, Glad to serve you. (1) The management tap of the bottom hole is a tool that cuts against the bottom hole. If the bottom hole accuracy is poor, the thread accuracy will also deteriorate, and it will also have a greater impact on the life of the tap.

Methods of triangular turning of internal threads:

There are two types of turning methods for triangular threads: low-speed turning using high-speed steel thread turning tools and high-speed turning using carbide thread turning tools.

Low-speed turning has high accuracy and good surface roughness, but low efficiency.

High speed turning speed and proper method can achieve high surface roughness.

External thread turning method:

Due to the poor strength of the tip of the triangular thread turning tool, the poor condition of the workpiece, and the cutting edges on both sides participate in the cutting at the same time, it will produce a large cutting resistance, which will cause the workpiece to vibrate, affecting the machining accuracy and surface roughness.

1) Low-speed turning.

Straight knife method: the transverse feed of the middle slide plate, which is suitable for turning the thread with a pitch of less than three and fine turning.

2) Left and right cutting method:

The middle slide is fed laterally, while the small slide moves the turning tool to the left or right slightly. It is suitable for rough and fine turning of various threads other than trapezoids.

When turning external threads, most of the allowance is cut off on the side in the direction of the tool; When turning internal threads, most of the allowance should be cut off on the tailstock side in order to improve the deformation of the tool holder.

3) Ramp method.

When the pitch is large, the thread groove is deep, and the cutting allowance is large, in order to facilitate the operation, the small slide plate only moves in one direction except for the straight forward of the middle slide plate. This method is only used for rough turning of threads, and the allowance for finishing is left on each side.

High-speed turning. High-speed turning can only use the straight method, but not the left and right feed method, otherwise the side of the hair profile will be pulled and the thread accuracy will be affected. At this time, due to the extrusion force of the turning tool on the workpiece, it is easy to make the workpiece expand, so the large diameter of the workpiece before turning is generally about smaller than the nominal diameter.

Want to make this clear? Not good to describe. Let's just talk about the order, let's take the through hole as an example:

The car has a good inner hole. Prepare the threaded cutter in the inner hole, and the tool holder and the knife head should have a certain gap in the hole, so as to be able to smoothly discharge and enter and exit.

Clamping the tool, draw a mark with chalk on the tool holder according to the length of the workpiece, and move the corresponding handle to the required pitch according to the nameplate.

Start the spindle, touch the tip of the knife to the inner hole of the workpiece and move it out longitudinally, remember that the horizontal handle scale is a little smaller, and close the nut.

After the knife is removed from the workpiece, the knife is retracted laterally, be careful not to be too large, quickly hit the reverse car or lift the opening and closing nut and repeat 6 7 to complete the size requirements.

If you have so many yards, you are idle.

To use a small turning tool, it is better to sharpen it yourself.

Turning methods for common threads.

Triangular threads.

Trapezoidal threads. Rectangular threads.

Pitch p mm

Turning method. Pitch p mm

Turning method. Pitch p mm

Turning method 3

Use a turning tool to enter the thread radially. Due to the large cutting force, the amount of back eating knife should be small.

3 Use a turning tool to enter the thread radially. Due to the large cutting force, the amount of back eating knife should be small.

4. The general precision thread can be turned with a turning tool, and the thread can be turned out of the radial feed tool. Precision threads need to be turned out twice with rough turning and fine turning tools.

Thread 3 rough turning adopts oblique feed mode, and fine turning adopts radial feed mode. If it is a precision thread, when finishing, the axial feed method can be used to refine it separately.

Thread type on both sides.

8. First, use a rough turning tool that is 2° smaller than the thread profile angle to the bottom diameter of the thread, and then use the same turning tool as the tooth profile angle to the radial feed finishing. ≤12

Respectively, use rough and fine turning tools to radially feed and turn out the thread.

3. The rough turning adopts the oblique feed method, and the finish turning adopts the radial feed method. If it is a precision thread, when finishing, the axial feed method can be used to separate the two sides of the finishing.

10 first use the groove cutter radially feed the tool to the bottom diameter, then use the rough turning tool with a blade inclination angle of 55 60 radially feed rough turning, and finally use the finishing tool with the chip chute radially feed the finishing turning, this method is also called "three knife method". 12

First, use the cutter to feed the car radially to the bottom diameter, and then use the left and right deflector cutters to axially feed the two sides of the fine turning tooth shape.

16. First use the cutter to feed the rough turning to the bottom diameter, then use the left and right deviation cutter axial feed to rough turn both sides, and finally use the same turning tool with the same tooth type to feed the cutter radially to finish turning.

Want to make this clear? Not good to describe. Let's just talk about the order of the late ruler, take the through hole as an example:

The car has a good inner hole. To prepare the inner hole threaded cutter, the tool holder and the cutter head should have a certain gap in the hole, so as to be able to smoothly discharge the pin and the high entry of the code shall prevail.

Clamp the tool and draw a chalk mark on the shank according to the length of the workpiece.

Move the corresponding handle to the required pitch according to the nameplate.

Start the spindle and touch the tip of the workpiece to the inner hole and move it longitudinally out of the hole, remembering the transverse handle scale.

Take a little knife in and close the nut.

After the knife is removed from the workpiece, the knife is retracted laterally, be careful not to be too large, and quickly hit the reverse car or lift the opening and closing nut.

Repeat 6 7 to complete the size requirements.

If you have so many yards, you are idle.

1. First find an aluminum nameplate above the feed box of the lathe;

2. According to the pitch you want to process (for example, the pitch is, according to the instructions on the nameplate, pull each handle on the feed box to the specified position;

3. Wrench the lead screw conversion handle to the "smooth bar" position, lift the lever, and see if the smooth bar also rotates when the spindle rotates;

4. Pair the tool, press down the "opening and closing nut" on the knife box, and test the thread.

5. For beginners, the spindle speed should be lower, about 50 rpm, and the feed amount is smaller.

There are 3 ways to process threads on lathes, and the master who knows this method must be a master.

The left and right turning method of threads is suitable for plastic materials, and is mostly used for turning triangular threads with large pitches and rough turning trapezoidal threads and zigzag threads. The left-right turning method is characterized by the fact that it can effectively prevent the phenomenon of "piercing" when rough turning plastic materials, and can improve production efficiency. The disadvantage is that the operation is complicated, the tooth shape is not easy to car, and the tooth shape error will be increased.

When using the left and right turning method to turn the trapezoidal thread, in order to make reasonable use of the turning tool and improve the production efficiency, you can first use the cutter to quickly turn out a spiral, leaving the allowance of fine turning, and then use the thread cutter to turn the tooth shape, and use the small carriage and the middle carriage to cross the transverse feed to turn the two sides of the thread and the bottom diameter respectively until the turning reaches the size. It should be noted that the cutting allowance on both sides of the tooth shape should be reasonably distributed, because the cutting conditions in the back direction are more unfavorable, so most of the allowance should be left in the direction of the knife.

r is calculated as:

1: Female thread: (large diameter at the beginning of the thread - large diameter at the end of the thread) 2=r positive 2:

External thread: (thread end diameter - thread start point diameter) 2 = r negative example: conical inner thread rc1 4 length is 20mm, starting point extension 5mm cone ratio is 1:

The major diameter of 16 1 4 is the front end).

The endpoint r is: (20+5*1 16) 2=

Programming: g00x11z5

z-20 i19

Turning triangular threads: calculation formula.

The thread marks m coarse teeth and nominal diameter.

m fine tooth nominal diameter pitch.

Tooth angle 60°

Thread diameter (nominal diameter) mm d d d=d thread diameter mm d2 d2 d2= d2=thread height mm h1 h1=

Thread diameter mm d1 d1 d1= d1=