Testing Times At Keighley Laboratories’ Test House
Engineering-based companies seeking premium quality, independent metallurgical testing, failure investigation, expert witness provision, positive material identification and quality assurance of finished components, need look no further than the long-established Test House at Keighley Laboratories. The UKAS accredited and ISO/IEC 17025:2005 certified testing laboratory offers a comprehensive array of expert facilities, from routine hardness, tensile, compression, impact and fatigue testing to European and American standards, through non-destructive testing (NDT) and inspection procedures applied by highly qualified technicians, to advanced metallographic analysis, employing state-of-the-art stereo binocular microscopes, advanced specimen preparation and digital image capture.
The Keighley Labs Test House, which includes a dedicated CNC machine shop for producing test samples, is staffed by around fifteen qualified technicians, trainees and graduates, maintaining formal in-house training procedures and a programme of CPD (continuous professional development) to ensure competency standards are preserved across all disciplines.
Our experienced metallurgical consultants are available for failure and fracture investigations, reverse engineering analysis and forensic-type examinations, providing full documentation and, where appropriate, remedial advice for preventing further problems. Unusually, the Test House services also include expert witness work in such areas as personal injury, accidents at work and welded joint failure, these specialised provisions often saving clients the considerable expense of litigation.
Independent metallurgical testing is widely employed to demonstrate meeting particular material specifications, as a customer requirement or legal obligation, and to identify why components have failed in service, so it is vital that the chosen test laboratory has the people, facilities and track record for producing valid and accurate data. That is why UKAS accreditation is important for us at Keighley Labs and our clients, since we demonstrate the technical competence of our personnel and availability of sufficient resources, as well as the impartiality of our advice and knowledge transfer. Indeed, the company regularly updates its comprehensive scope of UKAS accreditation, which can be viewed online at www.keighleylabs.co.uk/accreditations
Amongst the key functions of the Test House is the physical and mechanical testing of ferrous and non-ferrous metals and alloys to establish their mechanical properties, employing an impressive array of equipment and techniques. Impact testing, for example, measures the toughness of a material and its resistance to mechanical shock and Keighley Labs employs the two standard methods, Charpy and Izod testing, and have the capacity to prepare and machine test pieces. Hardness is the resistance of materials to permanent indentation and at the laboratory we offer the main Brinell, Rockwell, Vickers and Knoop microhardness and hardness testing methods, including portable instruments for evaluating in-service parts and samples too large to bring in-house.
Tensile and compression loading testing can be carried out in ambient, sub-ambient and elevated temperatures, with loads up to 1100kN; while digital equipment is used to fatigue- test components, employing resonant frequencies between 60Hx and 180Hz. Other mechanical testing techniques include proof loading, bend and fracture tests, and full metallurgical examination of fasteners. In a related sphere, corrosion testing of stainless steel, plated and painted test pieces, heat-resistant alloys and austentic materials is conducted using an array of neutral and accelerated salt spray techniques, chemical pitting tests and humidity chambers.
Our Test House’s metallography facility enables examination of the microstructure of metals and alloys, to determine such characteristics as grain structure, material inclusions and cleanliness, weld quality and case depth. Macro examinations up to 10x magnification and micro analysis to 1000x are undertaken on projector and stereo binocular microscopes, with photographic and video print functions, whilst semi-automatic sample preparation enables handling even the latest generation of superalloys.
All Keighley Laboratories NDT inspectors are qualified to either PCN Level 2 or 3 and are available for in-house and on-site work, at home or overseas. This accredited service covers the most common methods of inspection, Liquid Penetrant Testing, Magnetic Particle Testing and Ultrasonic Flaw Detection, with radiography additionally provided on a sub-contract basis.
Also in the field, non-destructive ferrite meters can identify the ferrite content of welded seams in pipelines and processing plant, which could lead to a decrease in mechanical or corrosion resistance if levels are incorrect. To complement this, magnetic permeability testing enables the accurate assessment of a material’s residual magnetism, which is critical for applications where stainless steels or copper alloys must have a very low or negligible response to electromagnetic fields.
Positive material identification (PMI) or alloy verification is used to determine the composition of a variety of materials, such as mixed metal stock, critical components, in-service pipework, valves and connections, and high grade alloys. Using the latest XRF (x-ray fluorescence) analysis equipment and Spark Emission Spectrometry techniques, Keighley Labs can undertake rapid PMI verification of most ferrous and non-ferrous materials, either in-house or on-site.
Our Test House customer base covers a wide variety of organisations, from high tech industries, through manufacturers using the service for ‘live’ QA testing on production components, to small engineering shops verifying that parts meet required specifications. Industry sectors served include aerospace, automotive, defence, oil & gas, rail & transportation, wind power and general engineering. Test pieces are typically finished components, either new production items or parts that have failed in service, or raw materials for verifying that they are fit-for-purpose, with size usually no obstacle since Keighley Labs can either produce smaller dummy samples or undertake testing at the customer site.