Simple, with large wall thickness difference and rounded hot spots at connections
High internal quality, compensate for welding deformation
Shrinkage porosity and sand holes in the rod hole area, low ultrasonic flaw detection qualification rate, and unqualified dimensions after welding and machining
Casting Difficulty Analysis
Difficulty Point
Specific Description
Impact on Casting
Meeting flaw detection requirements
High flaw detection requirements, multiple isolated hot spots, difficult to achieve sequential solidification
Affect the internal density of the casting and the qualification rate of flaw detection
Considering the influence of frame deformation on casting processing allowance and anti – deformation
Strict product size requirements, prone to deformation in multiple processes, and the influence of frame deformation needs to be considered
Affect the size accuracy of the casting and its ability to compensate for frame welding deformation
Ensuring casting size meets requirements
The inner dimension tolerance is – 2 ~ + 1mm, and the influence of multiple aspects on the size needs to be considered
Affect the overall size of the welded frame and its machining accuracy
Adjust the casting parting surface and the position of the riser, add subsidies and cold iron
Meet the flaw detection requirements and ensure the internal quality of the casting
Eliminate shrinkage porosity and shrinkage cavity defects in the flaw detection area
Adjust the size of the casting blank
Ensure the overall processing needs of the welded frame and the size accuracy
The size of the casting meets the drawing requirements, and there are no size and quality problems in the subsequent processing
Add ribs at specific positions and adjust the shrinkage scale
Prevent deformation during the production process
Effectively prevent deformation and ensure the size stability of the casting
Solidification simulation analysis before and after improvement
Simulate the original process and the improved process
Compare the solidification process and defect conditions of the two processes
The improved process realizes the expected temperature gradient field, and the casting defects are eliminated
New process production verification
Use the optimized process for production and verification
Verify the actual effect of the improved process
The casting quality is improved, the internal defects are eliminated, and the size meets the requirements
In the process of improving the casting process of the tie rod seat, the casting defect problem is effectively solved through a series of measures, which provides a reference for improving the casting quality of similar products. The following picture shows the casting defect distribution of the tie rod seat before improvement (left) and after improvement (right). It can be seen that the casting defect is significantly reduced after improvement.
In the formula for predicting casting defects, D=f(T,V,P), where D represents the casting defect, T represents the temperature field during solidification, V represents the cooling rate, and P represents the pressure distribution. By optimizing these factors, the casting defect can be effectively reduced. The improvement of the casting process of the tie rod seat is a comprehensive process that requires consideration of multiple factors to achieve the goal of improving the quality of the casting.
