【Caution for Cast Iron Weights】
1) Due to cast iron's good fluidity and minimal shrinkage in length and line, thin-walled, complex-shaped castings can be planned.
2) The mechanical properties of cast iron are highly sensitive to wall thickness, hence it is not advisable to increase the load-bearing capacity of castings by adding wall thickness. Instead, the objective of eliminating thick sections while maintaining load-bearing capacity can be achieved by modifying the shape of the cross-section.
3) Due to the higher compressive strength of gray cast iron compared to its tensile strength by a factor of 3-4, to fully exploit the unique characteristics of gray cast iron, it is advisable to commonly use asymmetric cross-sections, so that the cross-sections under compression stress on the casting are smaller than those under tensile stress.
4) When planning cast iron structural castings, the wall thickness should not be too thin, and the corners should be appropriately thickened to prevent white mouth from occurring, making the area hard and brittle, difficult to machine.
5) Cast iron has very little plasticity, so once deformed, it cannot be corrected as cast steel can. Therefore, when planning gray cast iron structures, it is advisable to follow the principle of simultaneous solidification and choose symmetrical structures. Design the structural and wall thicknesses to allow for natural contraction, preventing deformation cracks in the castings.
