precision custom machined part
The blank will directly affect the cost of mechanical processing.
when selecting the blank, it is necessary to consider not only the factors in heat processing, but also take into account the requirements of cold processing to reduce the manufacturing cost of machined parts.
There are four types of blank commonly used in mechanical processing.
1. Casting
We generally manufacture the blank of complicated parts by casting. There are mainly sand casting and special casting.
1.1 Sand casting used wood mold,the precision of blank is low,the machining allowance is large, and the productivity is low.It is suitable for small-scale production or large parts.
1.2 Special casting use metal mold,it has high productivity, high casting accuracy, but the mold cost is high, and the weight of the casting blank is also limited. It is suitable for small and medium-sized parts for large-scale production.
In addition, some small castings with high quality requirements can be special casting. Such as stress casting, centrifugal casting, investment casting,etc.
casting machining parts
2. Forging
We generally use forging blanks for steel parts with high mechanical strength requirements. There are two types of forgings.
2.1 Free forging
By hand forging (small blanks), mechanical hammer forging (medium blanks) or press forging (large blanks).This kind of forging has low precision, low productivity, large machining allowance, and the structure of the part must be simple; it is suitable for single-piece and small batch production, as well as the manufacture of large-scale forgings.
2.2 Die forging
The precision and appearance are better than those of free forgings, and the shape of the forgings can also be more complex, so the machining allowance can be reduced. The productivity of die forging is much higher, but it requires special equipment and forging dies, so it is suitable for small and medium-sized forgings with large batches.
Forging parts
3. Profiles
According to the shape of the section, there are round steel, squre steel, hexagonal steel, flat steel,angle steel, channel steel and other special-section profiles.
There are two types of profiles: hot-rolled and cold-drawn.
— Hot-rolled profiles have low precision, but are cheap, we use it for the blanks of general parts.
— Cold-drawn profiles are small in size and high in precision,are easy to achieve automatic feeding, we use them mostly in large batch production, suitable for automatic machining processing.
4.Welded parts
The advantages of welding parts are simple manufacture, short cycle and material saving. The disadvantage is poor vibration resistance and large deformation, it is better to precise mchining after heat treatment.
In addition, there are other blanks such as stamping parts, cold extrusion parts, powder metallurgy, etc.
