Common basic knowledge of CNC spinning

 A few important things to note in the heating spinning process

Heating and spinning are often used for products that are too thick or the material is prone to cold work hardening. Through heat treatment, the tensile strength and cold hardening of the material are reduced, and the material flow during the molding process is smoother. The following is the hot spinning process. A few important things to note:

1. Close the machine's protective cover

Due to hot spinning, the product needs to be heated during the forming process of the product. During the high-speed rotation of the material, the product will break. In order to prevent the material from flying out of the machine tool, it will cause danger to the processing personnel, and the protective cover needs to be closed during the production process.

2. Wear asbestos gloves when loading and unloading

As hot-spinned products, molds, and cutter wheels are at high temperature, asbestos gloves should be worn during the loading and unloading process to prevent thermal injury to the arms.

3. Isolate the processed product

Because the product is at a high temperature after hot spinning, it takes time for the product to cool, and it needs to be placed neatly and neatly to prevent the product from being burned.

Estimation of blank diameter for spinning

How to estimate the diameter of spinning materials, mastering a good method can effectively make an accurate quotation budget.

The quality of the blank is theoretically equal to the quality of the spinning product plus the loss during processing. Both:

Blank weight = spinning product weight + cutting edge loss + bottom cutting loss (cut off the weight of the bottom piece)

Cutting edge loss = weight of spinning product * 1%

Cut bottom loss = √￣πr²tp

Blank diameter = 2 * Blank quality / pπt

Note: t is the material thickness,  p is the material density.

The quality of spinning products can be weighed directly or measured using 3D modeling.

Demoulding principle and method of spinning products

Generally, CNC spinning products are demolded by air pressure. As shown in the figure on the right, after the product is processed, the machine releases gas through the blow hole to form a certain air pressure in the spinning mold. Because of the accumulated pressure in the blow hole, the pressure in the blow hole is greater than the external pressure of the product.

I. Several factors affecting demoulding of spinning products

1) Air pressure: Adjust the appropriate air pressure to control the demolding force to prevent the product from flying out and hitting the machine to cause damage.

2) Sticky material: Prolonged batch production will increase the temperature of the mold and the cutter wheel, because the melting point of aluminum is

The product is likely to stick to the mold and affect the release of the product. Applying some butter on the outer wall of the mold before the product is processed is beneficial to the release of the product.

II. Demoulding method of barrel-spinning products

Straight barrel products are generally very high in height. When the material piece and the mold are in close contact, the air pressure makes it difficult for the product to be demolded smoothly. When the conditions allow, a certain demolding angle can be designed on the mold. Or design the ejection thrust mechanism in the spinning mold.

Spin-off processing often results in blanking solutions

I. Reasons for material return during spinning

1. The gap between the cutter wheel and the mold is too small during strong rotation, which causes part of the material to flow toward the tail top.

2. The hydraulic top force of the tail top is too small, and the backward force of the material is greater than the thrust of the tail top.

3. Too many back passes of the forming tool path, resulting in excessive material flow to the tail top direction.

II. When material is returned from spinning, it can be judged from the following aspects:

1. The tail material of the product will exceed the flat surface close to the tail top and the blank.

2. There will be a certain gap between the end of the product and the end surface of the mold.

3. The rear end of the product will be partially uneven.

According to the above-mentioned phenomenon of returning material to analyze the specific cause of returning material, the problem of spinning returning material can be solved.