E-Archive

Nadcap Column

in Vol. 14 - March Issue - Year 2013
A Measured Approach To Measurement & Inspection

Dimensional measurement of components is routinely used throughout industry to verify the conformance of the manufactured product to the specification. To ensure measurements are reliable, it is important to ensure the measurement capability is suitable for the feature being measured. The capability to measure parts is influenced by a range of factors which can be broadly split into the following categories:
Calibration & Units: Processes used to maintain traceability of equipment to international standards and maintain a consistent set of units.
Product Definition: International drafting standards such as ASME Y14.5, company or product specific standards and their interpretation.
Inspection Planning: Processes used to plan the inspection process, usually to define what is inspected, where in the manufacturing process, equipment to be used and how the result will be recorded.
Equipment Validation: Selection and validation of the measurement equipment. Validation usually carried out with statistical methods such as Gauge R&R.
Maintenance and Environment: Maintaining a suitable measurement environment, effective temperature control is in place if required, ensuring equipment is stored correctly and in good condition.
Competencies: Staff specifying or executing measurements must be suitably competent to perform their role. Competency is usually demonstrated through a suitable testing process or observation.
Failure to implement and maintain effective measurement processes can lead to quality problems. It is therefore important for all aerospace manufacturers to operate effective measurement processes.
Currently, the aerospace industry does not have a unified approach to identifying measurement & inspection risks within the supply chain. However, experience suggests that there are many differing approaches to measurement & inspection in the supply chain.
Existing audit programmes such as AS9100 do not cover the full scope of measurement & inspection in the appropriate level of detail. Topics such as calibration are effectively covered, while others such as inspection planning or the detailed operation of specific equipment types like CMM¡¦s or Laser Trackers are only covered at a high level.
Within the Nadcap program, the development of a Measurement & Inspection accreditation is intended to provide adequate systemic and detailed auditing capability dedicated to the means, people, methods, and all other conditions required to be fulfilled in order to control the ¡§geometric inspection process¡¨. Like any other Nadcap audit, it has to be considered as a complement to a global 9100 quality management system: focusing on a very specific process at high stakes for any supplier and customer within the aerospace supply chain.
As a result, using the Nadcap program approach to apply ¡§like special process principles¡¨ to this Measurement & Inspection process has been determined as being the most adequate for continual enhancement. In common with other Nadcap accreditation areas, it is expected to help reduce scrap, rework and lead time; contribute to better-end product manufacturing; reduce overall cost for the industry; and improve the manufacturing process. At the October 2012 Nadcap meeting in Pittsburgh, the Nadcap Management Council approved Measurement & Inspection as a formal Nadcap Task Group. This means that Nadcap Subscribers and Suppliers can now formally meet to develop audit checklists. The scope of accreditation will initially cover dimensional measurement & inspection in the following areas:
Calibration and Units
Product Definition
Inspections ¡V Planning
Equipment Validation
Maintain & Environments
Competencies
The goal is to have checklists created and pilot audits conducted by the end of 2013, with feedback from the pilot audits reviewed and incorporated by the first quarter of 2014. The first Nadcap Measurement & Inspection audits are anticipated to take place in early 2014.

Learn more at www.pri-network.org/Nadcap/,
or contact Jim Bennett, Senior Staff Engineer:
jbennett@sae.org, or on +1.724.772 8651
Mark Aubele, Senior Program Manager: maubele@sae.org, or on +1.724.772 8654