01Drawing and technical revision
WhatVerify the drawing number, revision, technical changes and approval status used by the supplier, shop floor and inspectors.
WhyAn obsolete drawing can invalidate dimensions, material, interfaces or process requirements across an entire batch.
EvidenceControlled drawings, revision confirmations, technical clarifications and approved change records.
02Material and blank origin
WhatCheck material grade, specification and heat or batch number, together with the source and condition of cast or forged blanks.
WhyA nonconforming material or blank can alter strength, machinability, heat-treatment response and service life.
EvidenceMaterial certificates, heat records, blank supply records and required retest results.
03Datums, fits and critical tolerances
WhatConfirm machining datums, critical dimensions, geometric tolerances, fits and the agreed measurement method.
WhyDatum or fit errors can prevent assembly, destabilise operation or remove interchangeability.
EvidenceDimensional reports, gauge or CMM records, inspection plans and nonconformance dispositions.
04Heat and surface treatment
WhatCheck the process type, key parameters, hardness or case depth, surface condition, coating thickness and required pretreatment.
WhyUnder- or over-processing can cause distortion, cracking, accelerated wear or loss of protection.
EvidenceProcess records, hardness or case-depth results, coating inspection records and supplier release documents.
05Assembly interfaces and interchangeability
WhatVerify hole positions, shaft-to-bore fits, mounting faces, connection dimensions, orientation and adjoining-part interfaces.
WhyAn interface error can prevent installation or replacement even when individual dimensions appear acceptable.
EvidenceInterface measurements, trial-assembly photographs or reports, functional checks and approved deviations.
06Small-batch repeatability and packing
WhatCompare critical dimensions and process results between batches, then check rust, impact and positional protection in packing.
WhyBatch variation reduces spare-part interchangeability, while poor packing can damage conforming products before delivery.
EvidenceBatch inspection records, trend or sampling results, packing photographs and release checklists.