Where Does Poor Size Control Come From?
There are a number of reasons for China Mechanical Parts dimensional changes, some of which are:
Machines performing operations on workpieces may have inherent errors built in.
The tools used on the machine are prone to dullness, are generally worn, cracked, broken, and make a difference due to replacement or re-grinding.
The materials used for each part may vary slightly.
Machine maintenance plan is poor.
Incorrect cutting fluids can cause local cutting problems.
Participation of measuring equipment / tools / gages / equipment.
What size to check
When generating 2D technical drawings, it is important to understand the format of the dimensions and the tolerances involved, as well as critical and non-critical dimensions.
If a published product drawing has a common tolerance band throughout the product and has no critical dimensions, and if the part is to be assembled to another part, assembly or functional problems with the part or assembly sometimes occur.
If you tighten all dimensions to a very narrow tolerance zone, you may find that quality issues increase, there are more parts, and part costs increase.
If you don't understand the suitability of each component and do not apply tolerances to each area, you will have trouble during production.
Material error
Material selection is a vital part of the design process, and you need to first understand the features of the product.
Choosing the wrong material can result in poor quality of the finished product, as some materials are more difficult to process than others. For difficult-to-machine materials, achieving the right size repeatability can result in high reject rates during machining or poor parts reaching your production line.
