In precision machining parts, the primary specification requirement is, for example, the diameter of a cylinder, which is a severe requirement; The positive and negative difference is only the qualified part within the regulatory plan, otherwise it is the irrelevant part; The specification also has severe requirements; Negative parallax and positive parallax also need to be embedded into cylinders (such as very simple basic parts). When the diameter beyond the service planning is large enough, it cannot be penetrated. Assuming that the specific diameter is small enough to exceed the restraint of the negative service, there will be problems of penetration looseness and instability. These are all unqualified products. If the length of the steel cylinder is too long or too short, beyond the allowable planning, it will be attributed to irrelevant products. If the demand is invalid or is processed from scratch, it will inevitably lead to additional costs.
