What is the classification and development trend of forging?

Forging is a processing method that uses forging machinery to apply pressure to metal blanks to produce plastic deformation to obtain forgings with certain mechanical properties, certain shapes and sizes. It is one of the two major components of forging (forging and stamping). Forging can eliminate defects such as as-cast looseness and optimize the microstructure during the metal smelting process. At the same time, due to the preservation of complete metal flow lines, the mechanical properties of forgings are generally better than those of castings of the same material. For the important parts of machinery with high load and severe working conditions, forgings are often used except for simpler shapes that can be rolled, profiles or welded parts.

1. According to the different classification of tools and molds used for hot forging steel

Forging can be divided into the following categories according to the tools used and the placement of molds:

1. Free forging uses certain tools and equipment to use impact force or pressure to make the metal flow freely to the four sides between the upper and lower iron (anvils) to deform to obtain the required forgings. There are two main types: manual forging and mechanical forging.

It is characterized by flexible technology, low processing accuracy and low cost, and is suitable for single-piece and small-batch production.

2. Tire die forging First use free forging to forge the initial shape, and then use the tire die to make up to improve the accuracy of the blank shape.

Its characteristics: flexible technology, high processing precision, suitable for small and medium batch production.

3. Die forging Die forging is divided into open die forging and closed die forging. The heated metal billet is put into a forging die bore with a certain shape, and the die is closed to form a forging.

Its characteristics: single product, high processing precision, simple operation, high production efficiency, suitable for mass production.

2. Classification by forging deformation temperature

1. In the forging process where the final forging temperature is higher than the recrystallization temperature, the workpiece temperature is higher than the die temperature.

2. Isothermal forging The die is equipped with heating and heat preservation devices, and forging is carried out at a constant temperature.

3. Cold forging refers to forging performed at room temperature or below the recrystallization temperature of the workpiece.

4. Warm forging is between hot forging and cold forging.

3. Die forging is classified according to movement mode

1. Ordinary die forging is characterized by the linear reciprocating movement of the die relative to the blank.

2. Spoke forging The blank moves in a straight line, and the two-spoke forging die moves in a rotating motion. The direction of rotation is opposite, and the rotation axis is perpendicular to the direction of blank movement.

3. The axis of the cross-rolling spokes are parallel to each other and the direction of rotation is the same. The axis of rotation of the rolling piece is parallel to the axis of rotation of the spokes, but the direction of rotation is opposite.

4. The skew rolling report axis crosses at a small angle, and its rotation direction is the same. The rolling piece moves on the center line of the intersection of the two series in the opposite direction to the rotation of the spoke.

5. Swinging The swinging head also revolves in addition to its autorotation. The workpiece does not rotate, but it has an axial feed movement.

6. Radial forging Several hammer heads are symmetrically distributed around the blank, and they are fed radially along the blank. High-frequency synchronous forging. The blank is usually fed while rotating.