How to choose good quality iron castings What factors a […]
How to choose good quality iron castings
What factors affect the quality of iron castings? Today, our Iron Manufacturing Co., Ltd. will give you a brief analysis:
1. The geometry, size, size effect and solidification, shrinkage and stress of iron castings.
2. The structure, weight and size of iron castings.
3. The quality of raw materials used in casting iron castings. The quality of metal charge, refractory materials, fuels, fluxes, modifiers, foundry sand, sand binder, paint and other materials are substandard, which will cause pores, pinholes, slag inclusions, sand sticking and other defects in iron castings, which will affect iron castings. The appearance quality and internal quality will cause the iron casting to be scrapped in serious cases.
4. For the process operation of iron castings, it is necessary to formulate reasonable process operating procedures to improve the technical level of workers so that the process regulations can be implemented correctly.
Advantages of lost foam casting process
The lost foam casting process has advantages in three main aspects: technology, economy and environmental protection.
1.2.1 Technical aspects
1) Increased freedom of model design
It is possible for the new process to carry out styling design, and it is entirely possible to add some additional functions to the model from the first stage. For example: the diesel preheater has a special functional part, which can be manufactured by the lost foam casting process instead of the traditional casting method.
2) Eliminate the sand core used in the production of castings
3) Many castings can be fed without riser
4) Improve casting accuracy
Complicated shape and structure can be obtained, high-precision castings can be produced repeatedly, and the wall thickness deviation of castings can be controlled between -0.15~+0.15mm
5) There is no flash on the joint surface of the model
6) It has the advantage of reducing the weight of castings by about 1/3
7) Reduce machining allowance
The machining allowance can be reduced, and some parts may not even be processed. This greatly reduces the investment in machining and machine tools (for example, the investment can be reduced by half for different situations).
8) Compared with traditional cavity casting, mold investment is reduced.
9) Completely eliminate the traditional sand falling and core out processes
1.2.2 Economic aspects
1) Can produce complex castings as a whole
Adopting the new process design, the block model can be glued to form an overall model and cast into a complex integral part. Compared with the original multiple casting assembly parts (such as diesel preheater), it can benefit from 1 to 10 times.
2) Reduce workshop personnel
The establishment of lost foam casting factories has fewer employees than traditional casting factories, so this factor should be considered.
3) Flexible casting process
The flexibility of the casting process is very important, because the new process may simultaneously produce a large number of similar or different castings in the flask, and the gating system is therefore very flexible. In short, we can say that each advantage is consistent with economic interests, while also improving working conditions.
1.2.3 Environmental protection
Polystyrene and PMMA produce carbon monoxide, carbon dioxide, water and other hydrocarbon gases when burned, and their content is lower than the European standard. Dry sand can use natural silica sand, which is 100% recyclable and does not contain binder. The paint used in the model is composed of additives such as binders in the water, which does not cause pollution.