CASTING PROCESS AT VAN VOORDEN FOUNDRY
With more than 100 years of experience Van Voorden Foundry has evolved into a specialised and modern foundry. To give you an idea of our production method, we would like to show you our sand casting process step by step.
At Van Voorden we use the method of sand casting. Sand casting is a technique, commenly used in iron foundries.
To create a casting we need a 3-dimensional moulding of the required product. To obtain such a mold we need to imprint the model into sand. this cavice will later be filled with liquid metal. The solidified shape is then called a rough casting.
Please find the 7 steps of sand casting hereunder:
Step 1: Judging castability
Van Voorden checks your 2D and 3D drawings for castability and solidification. This solidification process is simulated with Magmasoft software. Van voorden always strives to achieve the 'First Time Right' principle.
Step 2: Calculating gross casting weight
To make the casting according to specifications, Van Voorden needs to calculate nett and gross casting weights. During the solidification process there is always some form of shrinkage. Additionally, material is added on surfaces that need to be machined after casting. Furthermore, a casting system needs to be taken into consideration. This casting system (including risers) should guide the metal to the mould. All this makes it necessary to melt more metal (gross) than the actual casting itself (nett).
Step 3: Making a casting model
The next step is making a wooden casting model. With this model an imprint is made into the sand. This model is usually made out of wood, but can also be made out of EPS (styrofoam). Van Voorden also has possibilities to make the model out of hardened sand with a 5-axis sand mill.
Step 4: Forming
Shaping the model and creating the casting system is called forming. The casting systems is designed to ensure a gradual filling of the cavity. The risers are on top of the casting (usually cone-shaped) and should ensure a gradual supply of liquid metal to the casting, avoiding porosity. Finally, the cavaties are coated with a water or alcohol-based solution to protect the sand from the liquid metal.
Step 5: Casting the product
The casting manager at Van Voorden is responsible for the correct alloy, the melt and temperature during casting. With large induction furnaces the raw materials are molten into liquid metal. This liquid metal is then cast at the correct temperature into the mould. The casting then solidifies and is broken out of the mold when it reaches the correct temperature.
Step 6: Deburring the casting
After casting the casting system and risers need to be removed from the product. This is done through grinding and sawing. After this the casting needs to be sanded to prepare it for further machining. Some materials, made out of white casting irons, RVS or Nickel-Aluminum-Bronze, need to be heat treated to ensure extra durability and/or to release tension within the material itself. This also happens within the factory with a computer-controlled gas oven.
Step 7: Machining
As one of the final steps, the casting can be machined according to the technical drawing. When completed, the various reports can be made with information regarding the exact chemical composition, hardness, tensile strenght and/or ductility.
Upon request the casting can also be examined with dye penetrant/ultrasonic or magnetic testing.
CONTACT VAN VOORDEN FOUNDRY
Are you curious as to what we could do for you? Send your technical drawing (2D or 3D) with the request form to our sales department. Together with our mettalurgist and our process technologist we judge your drawing for castability and you will receive our offer as soon as possible.