IGI Incoming Goods Inspection services are quality control services which are performed on all shipments of goods from suppliers upon arrival at the customer's plant in order to detect potential failures of components or materials prior to their entry into warehouse areas and production lines.
What are inspection-receipt services?
The inspection-receipt services seek to detect possible failures of the components through visual inspections, functional tests, dimensional inspections, tests with gauges, counting of units received, review of packaging among many others. The main objective of this process is to validate the conformity of a batch of parts based on the quality, logistics and engineering characteristics indicated in the Control Plan. These inspection-receipt services shall be based on the international standards ISO2859 or ISO3951 on the basis of which the statistical methods and operating rules for incoming quality control processes shall be defined.
This service is not performed by 100% inspection of received parts. Validation is determined based on a sample of parts which is indicated within the Control Plan of the components or, failing that, must be based on the military standard "MIL-STD" or "MIL-SPE by its acronym in English United States Military Standard.
It is necessary to consider that this service is extremely important since there are two types of risk in this process. If material scrap is high, on the one hand production lines are protected in terms of quality but for just-in-time JIT systems the process will be destabilized due to material shortages. On the contrary, if a defective batch is considered as acceptable and it is released to the production lines, this will have a negative effect on the quality of the processes causing also the instability of the process due to assembly, manufacturing or other problems.
Shipments or batches of material can be determined as AQL (Acceptable Quality Level) or NQT (Tolerated Quality Level).
The fundamental difference between Inspection-Receipt Services (IGI) and Statistical Process Control (SPC) services lies in the lack of production sequence in the control tables. In the services of Inspection-Receipt or Incoming Quality Control samples are taken randomly from the lot or shipment in question so that no notion of time between them (it is not known whether sample A was manufactured before sample B) while the Statistical Process Control Services (SPC) samples are taken always in sequence so that changes in the process can be detected according to their manufacturing dates. Another big difference between both services lies in the interpretation of the results where the final action of the services of Inspection-Receipt is that of accept or reject the entire batch of materials and in the case of Statistical Process Control the interpretation of results is dynamic and proactive using graphs to determine when to change or adjust the process to avoid poor quality.
The Inspection-Receipt Services (IGI) can be carried out in a light (reduced) or increased (reinforced) way depending on the history of faults presented by the supplier as well as can be determined a sampling scheme simple or classic we take all samples before making the acceptance/rejection decision or by a sequential sampling method where we stop taking samples as soon as we are sure that the lot is good enough or bad enough.
The data report of the Inspection-Receipt Services (IGI) can be basic indicating only general data such as part number, lot number, date of inspection, number of pieces inspected in sample and the determination of whether the lot was accepted or rejected, can be moderate indicated also the record of the measurements of each sample according to the data requested within the Control Plan and can be advanced including variable control charts for dimensional measurements.
All these possibilities are related to the initial risk we decide to take in which we can change the sampling, acceptance rules and statistical confidence in the data obtained.
The proper implementation of Inspection-Receipt Services (IGI) helps reduce the time of processes related to Quality Control in production processes by up to 50% and reduces the risk of manufacturing failures by up to 35%.