
difference between forging and casting
What is the Difference between Forging and Casting Production Method of Crane Wheel?
There are many things to pay attention to in forging and casting production methods, but not every item needs strict attention. What is the difference between forging and casting production methods? The following article mainly tells you about it.
Forging is a processing method that uses external force to plastically deform a blank (metal) to obtain a blank or forged part with the required size, shape and performance. It is one of the main methods of blank production in machinery manufacturing.
1) The metal materials used for forging should have good plasticity so that they can undergo plastic deformation without cracking under the action of external forces. Among commonly used metal materials, cast iron has poor plasticity and is a brittle material that cannot be used for forging. Copper, aluminum and their alloys among steel and non-ferrous metals have good plasticity and can be used for forging.
2) Through forging processing, casting structural defects such as pores and shrinkage porosity of the ingot can be eliminated, micro-cracks can be pressed together, and a denser crystalline structure can be obtained, which can improve the mechanical properties of the metal.
3) Forging processing is solid-state forming, and it is difficult to manufacture parts with complex shapes, especially parts with complex inner cavities. After forging, the internal structure of metal materials becomes denser and more uniform, and can be used to process important parts that bear heavy loads and high rotational speeds.
4) Forging is suitable for scenarios that require high performance, heavy load, and high wear resistance of crane wheels.
5) Since the metal blank is subject to strong impact and pressure during the forging process, the forged crane wheel usually has a more uniform structure and higher mechanical properties, such as strength and wear resistance.
6) Forging usually requires higher investment in process technology and equipment, because the forging process has higher requirements on equipment and usually requires more manual operations.
Casting refers to the forming method of melting metal, manufacturing cast, and pouring molten (or liquid) metal into the cast, and obtaining a certain shape and performance after solidification. Castings are usually made as blanks and machined into parts. Casting forgings are generally divided into sand casting and special casting. Sand casting is the most common application. Sand casting is a casting method using sand compaction forming. The sand mold is damaged after taking out the casting, so the sand casting is also called one-time casting. Casting is one of the main process methods of blank forming and plays an important role in machinery manufacturing. According to the quality calculation, castings in general mechanical equipment account for about 40% to 90%; In agricultural machinery accounted for 40% ~70%; 70% ~ 80% in metal cutting machine tools; In heavy machinery, mining machinery accounted for more than 85%. Casting can be so widely used because it has a series of advantages:
1) It can produce castings with complex shapes, especially complex inner cavities. The quality of the casting can be from a few grams to hundreds of tons, and the contour size can be from a few millimeters to tens of meters. For example, the machine bed, the cylinder block and head of the internal combustion engine, the valve body, the box and the hydraulic press beam are all blanks.
2) Various alloys can be used to produce castings. Such as: cast iron, cast steel, alloy steel, copper alloy, aluminum alloy and other metal materials can be used for casting, especially for brittle metal materials (such as gray cast iron), difficult to forge and cutting alloy materials, can be used to produce parts and blanks casting method.
3) It can be used for both single-piece production and batch production.
4) The shapes and sizes of castings and forgings are very close, so the machining allowance of castings is small, which can save metal materials and processing man-hours.
5) The cost of castings is low. The equipment used in casting is relatively low-cost and the raw materials are cheap. In casting production, all kinds of metal waste (such as pouring risers, waste machines, waste castings) can be reused. In addition, in most cases, production preparation is simple and the production cycle is short.
6) Casting is suitable for scenarios where the crane wheel performance requirements are relatively low, the load is small, and the cost control requirements are high.
In general, forging and casting are two different production methods, and which production method to choose depends on the specific needs and requirements. If the performance requirements for crane wheels are high, forging is usually chosen; if the cost control requirements are high and the performance requirements are not very strict, casting can be chosen.