How Do Steel Casting Manufacturers Control the Quality?

(1) Control of chemical composition:

In order to ensure that the chemical composition of the casting is within the standard, the steel casting manufacturer must conduct a rapid analysis of the molten steel before pouring. Pouring can only be carried out after the composition is qualified. Otherwise, the composition of molten steel liquid shall be adjusted. Pouring can be carried out after the composition is qualified, and then the direct reading spectrometer shall be used for rapid analysis in front of the furnace.

(2) Control of mechanical properties:

During pouring, steel casting enterprises can use molten steel from the same furnace to make standard samples after heat treatment and machining in the furnace, and then conduct mechanical property tests on them.

(3) Surface quality control:

Before the casting leaves the factory, the casting will be inspected, and the steel castings shall not have defects such as cold shuts, cracks, and shrinkage porosity that affect the service performance.

(4) Size control:

In the process of converting large steel castings from drawings to models to castings, problems in each step will cause errors and lead to changes in a geometric shape. Measurement is also one of the indispensable processes for detecting the spatial position of the model and casting. To produce a greater surface polish or tighter tolerance, post-processing is necessary due to the limitations of the casting process. These essential dimensions must be thoroughly examined. Common inspection procedures for dimensions in casting companies include:

– Measuring tools: the most direct and straightforward approach for measuring measurements and tolerances is to use measuring instruments. To assure the product’s quality, we must utilize measurement instruments to test each significant dimension against the blueprint. Cast steel is commonly measured with a vernier caliper, depth indication, dial indicator, etc.

– Test instruments: built in accordance with dimensions that may affect product assembly or use. When the measuring instrument is incapable of testing the dimension, the test instrument is typically employed. For threaded holes, go and no-go gauges can be obtained from the market in accordance with thread specifications.

– CMM: The most precise measuring equipment available. However, CMMs are extremely expensive, and only a few foundries own them.

As for the method of quality control of steel castings, we need to pay special attention to each process in the process of casting. If we do not pay attention to it, it will lead to problems in the later procedures of steel casting enterprises, and the final castings produced will also be unsatisfactory.