We’ll continue from where we left in the previous blog. Here is the information required to be considered in your request for a quote.
- Design/Drawing files:
Drawings and specifications of the parts requests (but not limited to):
- Dimensions & geometry
- Dimensional tolerances within acceptable limits
- Stress/load needs
- Machining requirements
- Non-destructive test requirements
Material information should incorporate a particular metal grade or the desired material and preferred properties. Materials specs are usually furnished using an internationally recognized material standard such as ASTM. Casting costs are drastically impacted by the material chosen due to the inherent metal’s or alloy’s cost and its castability.
- Actual or estimate weight:
Weight is an important factor for the calculation costs for sourcing materials, shipping and processing. Actual weight is desirable, as inaccurate estimates may result in inconsistencies between actual and estimated costs.
If you already have the patterns and core boxes, your quote request should specify the type, set up and condition of the equipment. An existing pattern in appreciably good condition may lower the cost of your casting run.
If existing patterns aren’t available, you need to spend on pattern equipment design. When you spend more on sophisticated pattern equipment, what you get is higher casting quality and lower casting cost. Most misunderstanding occurs due to not communicating your requirements clearly in the planning phase.
Incorporate the expected volume, both present as well as future. Quantity can impact pattern development and the production methods and overall costing. Various pattern materials are appropriate for future, high-quantity production runs. The production efficiency improves with sizeable order volumes.
- Acceptance Criteria:
Material property test criteria, cast surface finish and casting sounding are critical requirements for a project quote. The soundness of metal castings is defined as the point of freedom from discontinuities and impurities including shrinkage, macro porosity and inclusions. There is some degree of defect in all castings—the acceptance criteria outlay what degree and defects lie within acceptable limits. Acceptance criteria and testing methods should be in agreement prior to production. The tighter and tested the acceptance criteria, the more expensive the finished product will be (without basically increasing serviceability or quality). The acceptance criteria and rigorousness of testing should be in accordance with the service and design requirements. Some more considerations to follow in the concluding part of the three-part series of the blog.