What should I pay attention to when a lathe uses external clamping to process thin walled parts?

Note that the radial force is wrapped in copper to make it evenly stressed

In turning, the commonly used ways to clamp the workpiece include the following:

Manual three-jaw chuck: It is a common clamping method, suitable for the processing of small and medium-sized workpieces, and the workpiece is clamped by manually rotating the center nut of the chuck.

Automatic chuck: Automatic chuck is an upgraded version of chuck, which has the function of automatic clamping and automatic release, which can improve production efficiency and processing accuracy, and is suitable for high-volume production and processing.

Hydraulic chuck: the hydraulic system is used to achieve clamping, with large clamping force and good stability, and is suitable for processing workpieces with large loads.

Elastic fixture: Clamping the workpiece by elastic deformation, suitable for workpieces with complex shapes and sizes.

Template Hui key fixture: suitable for mass production, through pre-made templates, you can quickly realize the clamping of workpieces, improve production efficiency.

Steady rest: suitable for processing long and thin workpieces, the two ends of the workpiece are fixed through the steady rest to ensure machining accuracy and stability.

Inflatable fixture: The workpiece is clamped by inflating, which is suitable for precision machining and no damage to the surface of the workpiece.

Different clamping methods are suitable for different occasions, and choosing the appropriate clamping method can improve processing efficiency and processing quality. When choosing the clamping method, it is necessary to consider the shape, size, weight, material and other factors of the workpiece, as well as the processing requirements, process flow and other factors.

When turning, the commonly used clamping methods are: three-jaw chuck, four-jaw chuck, faceplate, or machining with two centers against both ends.

Clamping method for shaft workpieces.

1. Three-jaw self-centering chuck (commonly known as three-jaw chuck) clamping.

Features: The self-centering chuck clamps the workpiece conveniently and time-saving, but the clamping force is not as large as the single-action chuck.

2. Four-jaw single-action chuck (commonly known as four-jaw chuck) clamping.

Features: Single-action chuck alignment is time-consuming, but the clamping force is larger.

Application: It is suitable for clamping large or irregularly shaped workpieces.

3. One top and one clamp clamping.

Features: In order to prevent the axial displacement of the workpiece due to the action of feed force, a limit support can be installed in the taper hole at the front end of the spindle, and the step of the workpiece can also be used to limit the position.

Uses: This method is safe and reliable for clamping, can withstand the large feed field rock force of Qizheng, and is widely used.

4. Clamp with two centers.

Features: It is convenient to clamp the workpiece with two centers, no need to align, and has high positioning accuracy. But the stiffness is lower than that of clamping and clamping, which affects the increase of cutting amount.

Uses: Workpieces that are long or must be clamped several times before they can be machined, or workpieces that have many operations and need to be milled or ground after turning.

Before clamping the workpiece, the carbon in the workpiece must be removed from the sand and mud and other impurities, so that the impurities are embedded into the sliding surface of the carriage, which will aggravate the soft wear or "bite" the guide rail.

When clamping and correcting some workpieces with large size, complex shape and small clamping area, a wooden bed cover plate should be placed on the lathe bed surface under the workpiece in advance, and a pressing plate or a movable thimble should be used at the same time.

Resist the workpiece, prevent it from falling and smashing the lathe, if you find that the position of the workpiece is incorrect or skewed, do not knock hard, so as not to affect the accuracy of the lathe spindle, you must first loosen the gripper, pressure plate or thimble slightly, and then carry out step-by-step correction.

To choose a clamp-on indexable insert, you must first understand the indexable insert model representation rules. According to the international scale i, the ** representation of indexable blades is made up of 10-bit strings.

In general, the 8th and 9th digits of ** are filled in when required. You can add some additional symbols, using hyphens.

Connect it to ISO** (e.g. PF stands for chipbreaker geometry). Indexable inserts are used for different processing methods such as turning, milling, drilling, boring, etc., and the details of their ** are also slightly different.

1. If it is an unprocessed surface, it is required however, as long as the clamping is parallel, and the 1 3

2. If it is a processing surface, it is necessary to pay attention to the force, otherwise it is easy to pinch the workpiece. (for small workpieces).

3. Factors affecting the machining accuracy of thin-walled parts.

1) Prone to force deformation: due to the thin wall of the workpiece, under the action of clamping force.

It is easy to deform, which affects the dimensional accuracy and shape of the workpiece.

shape accuracy; 2) Prone to thermal deformation: due to the thin workpiece, the cutting heat will cause the thermal deformation of the workpiece, making the size of the workpiece difficult to control;

3) Easy vibration deformation: in the cutting force (especially radial cutting force).

Under the effect, it is easy to produce vibration and deformation, affecting the workpiece.

Dimensional accuracy, shape, positional accuracy, and surface roughness.

One:1During the clamping process, it should be possible to maintain the correct position obtained when the workpiece is positioned2

The clamping force is appropriate. The clamping mechanism should be able to ensure that the workpiece does not loosen or vibrate during the machining process, and at the same time avoid inappropriate deformation and surface damage of the workpiece. The clamping mechanism is generally self-locking.

3.The clamping device should be easy to operate, labor-saving and safe.

4.The complexity and degree of automation of the clamping device should be adapted to the production batch and production method. The structural design should strive to be simple, compact, and use standardized components as much as possible.

2: Commonly used clamping mechanisms are: oblique wedge clamping mechanism, spiral clamping mechanism, eccentric clamping mechanism, hinge clamping mechanism, centering clamping mechanism, and lever clamping mechanism.

Remember to operate the machine safely, do not wear gloves, wear glasses, wear long-sleeved clothes, the cuffs should not be too loose or should be rolled up, and the wrists should not wear jewelry. Chuck clamping workpiece method, when installing or removing the workpiece, hold the workpiece with the right hand and the palm of the hand inward to avoid the hand or the long workpiece touching the turning tool, and at the same time hold the T-wrench in the left hand and insert it into the square hole on the outer circular surface of the chuck (the hand is required to leave the square hole at the same time from the wrench, and do not put the wrench alone on the chuck at any time) After the workpiece is placed in a suitable position, fix it slightly tightly with a T-wrench, and then clamp the workpiece with both hands, and finally start the machine.

Three-jaw self-centering chuck, four-jaw uncentering chuck, double center clamping, flower disc angle iron clamping, center frame assisted clamping. Other specially-shaped workpieces are also available with special fixtures. specific classification;

1: Positioning of the cylindrical surface outside the workpiece (three jaws. Four claws. Spring chuck, sleeve) 2: The workpiece is positioned in the inner hole (rigid mandrel. Splined mandrel. Spring mandrel) 3, the workpiece is mainly positioned in a plane (faceplate, pressurized plate and angle iron synthetic fixture).

1) Four-jaw single-action chuck clamping This kind of chuck clamping force is large, but it is more time-consuming to align, and it is suitable for clamping large or irregular shape workpieces.

2) Three-jaw self-centering chuck clamping This chuck can be automatically centered, does not need to spend too much time to align the workpiece, the clamping efficiency is higher than the four-jaw single-action chuck, but the clamping force is not as large as the four-jaw single-action chuck, suitable for clamping small and medium-sized regular workpieces.

3) The clamping method of two centers is more convenient, no need to align, and the clamping accuracy is high. It is suitable for long workpieces that require high clamping accuracy (such as axial requirements) and must be processed by multiple clamping, or workpieces with many processes.

4) One clamp and one top clamping method clamping workpiece is safer, can withstand large cutting force, suitable for heavy clamping, long occasions.