How to control the casting quality of cast iron and
cast steel products made in China
I have worked in China foundries for years
as a marketing manager, so I have met many quality complains and
problems, so I am thinking how to control the cast iron and cast
steel casting quality.
Many importer and trading companies were heating to import metal
castings parts, especially cast iron and cast steel casting parts,
this is because there are many quality problems with them. Even if
you find a very good foundry as supplier in China, looks like
quality problems will happen anyway.
The basic reasons are two aspects. One is the casting production
processes are very complex and there are many aspects which will
affect the quality. Second reason is the workers’ skill and quality
is very low and different in China foundries. The working conditions
are bad in foundries, so only farmers and physical working man are
willing to work in this condition, so they will affect the stable
However, in India, their quality of workers will be worse than
Chinese, so you will have to import casting parts from China anyway,
then you will need to hear about the following suggestions to
control the quality.
Inspection reports are very effective and useful method to control
the quality of iron and steel castings. The reports will prove that
the foundries have performed the inspection, and they also promise
the casting quality as the reports.
Material report includes chemical composition, and mechanical
properties, including tensile strength, yield strength, hardness,
nodular rate, etc.
Dimensional reports will show the inspection results to the
dimensions. Our Dandong Foundry also shows surface quality and other
inspection results on the dimensional reports.
Inspection tooling is very useful for the manufacturer to control
the quality. For example, if this metal casting part needs to
assemble with other parts, then if it is possible, please send these
parts to the manufacturer, so they can use them as the inspection
tools. Otherwise, suggest the foundries to make some inspection
tools for the key dimensions. For tapping thread, you could send
some No-Go gage to the foundries or tell them the exact types, so
they could buy them in China.
Personally, I think inspection tool will be more useful to control
the dimensions than dimensional reports.
If you want to check the surface quality, painting and packing, then
you could require the Chinese foundries to take some photos for the
metal castings. Please believe me that they are useful. Many of our
clients discussed quality issues with us by photos with denotation,
which has helped us to solve many problems.
4. ASK FRIENDS TO INSPECT
If you want to inspect the casting quality or want to survey a China
foundry, but you do not have time to do so, then you could ask one
of your suppliers to help you to do so. I have helped many clients
to do the factory investigation. After I review their Chinese website and calling to their contact, I will make a personal opinion
to judge if they are cheater, if they are qualified, and if skillful
to complete the products of yours.
Sometimes, we can send an inspector to site to inspect the quality.
One aspect, we could inspect some problems. Second aspect, the
suppliers will notice that you have inspectors in China, so they
will control the quality stricter than normal.
5. ENTRUST THIRD PARTY INSPECTION
If you have lots of money, and inspection is very important for you,
then you could try to entrust the third party inspection company to
site inspecting. However, one disadvantage is very high cost,
another disadvantage is they can not find out the quality problems.
Most of Inspection Company or organization declared that they can
inspect quality, but actually, they just could do some simple
dimensional inspection. Even if they have some inspection devices,
such as UT inspector, their devices are not almighty, they can find
out some big quality problems, but can not find out small problems.
Our foundry does not have resistance to third party inspection,
moreover, during each time inspection, we can learn more knowledge
from them, and however, what I said is also the truth. I just said
the third party inspection is not almighty, and the result also
depends on their real capability, not as their propaganda.
In addition, please try to tell you supplier
how you will use these casting parts, sending some assembly drawings
or photos to them, this information will be the best for their
quality control. Many clients may think this is necessary, you just
need to meet the tolerance and requirements on the drawing, no need
to understand how we will use them. Actually, this is the biggest
mistake. This information will help the manufacturers to know the
key dimensions, the main requirements to surface quality, and inside
defects. Please, please believe me, this is very important.