Keighley Laboratories Offers Advanced NDT ResourcesNon destructive testing

Non-destructive testing (NDT) is a highly valued quality assurance and analytical technique that helps safeguard against the potential failure of engineering material, components, fastenings and structures. Since it enables in-depth evaluation of a material without causing damage, NDT often provides the final QA stage before a new product enters service, while in-service NDT can be the last line of defence against component failure in the field.

As part of its broad range of advanced metallurgical solutions, Keighley Laboratories offers a specialised NDT service for clients in the aerospace, automotive, petrochemical, nuclear, defence, mechanical engineering, construction, civil engineering and allied industries, covering both laboratory and site inspection. The company continually invests in staff training and new technology to expand its capabilities.

The Keighley Labs NDT facility covers the two most common methods of surface crack and flaw detection, Liquid Penetrant Testing and Magnetic Particle Testing, and the mainstream volumetric inspection technique, Ultrasonic Flaw Detection, as well as providing Radiographic Testing services on a sub-contracted basis. Non-destructive testing and inspection procedures are highly operator-dependent, relying upon the skills and experience of NDT technicians to obtain and evaluate results, and all members of the Keighley Labs team are certificated to a minimum of PCN Level 2, an internationally recognised symbol of competence. Indeed, Senior NDT Engineer, Roger Wheatley, is qualified to PCN Level 3 and able to develop NDT procedures, write instructions, audit techniques and both train and examine Level 1 and 2 candidates, making him a valued asset for both the company and its customers.

“We like to think of ourselves as the best, with a high degree of technical skill and experience, able to handle the most critical components,” says Roger. “Although most of our work is carried out in the lab, around 20 per cent of projects are on site, checking fixtures that cannot be moved like motorway bridges, presses, silos, boilers, offshore rigs or miles of installed pipelines in paper mills and petrochemical plants.”

For the detection of surface breaking flaws on ferrous and non-ferrous materials, such as casting and forging defects, weld cracks, leaks in new components and fatigue cracking on in-service components, Keighley Labs provides Liquid Penetrant Testing with either colour contrast or fluorescent techniques, working to national and international standards including BS EN 571:1997. LP testing can be undertaken either in the firm’s laboratory or at the customer site.

Magnetic Particle Inspection is conducted on ferro-magnetic materials, by inducing a magnetic field into the test piece, and is ideal for detecting cracks, porosity, seams and other surface breaking, as well as sub-surface discontinuities down to 2mm. Imperfections are revealed using fluorescent or non-fluorescent media; on-site testing is carried out using permanent magnets or portable electro-magnetic yokes where a suitable power source is available. Suitable for welds, castings, forgings and machined parts, including engine, suspension and braking components, testing is carried out by Keighley Labs to BS EN ISO 9934-1 and BAE RO5-6103 standards.

For identifying imperfections within a test piece or any changes in material properties, Ultrasonic Flaw Detection reveals volumetric discontinuation, utilising sound waves introduced into the component from an ultrasonic source. Undertaken by digital and analogue machines, ultrasonic detection is able to penetrate up to 10m in steel and can detect laminations, lack of fusion and any corrosion, as well as carrying out thickness and depth checks. This technique is suitable for welds, wrought iron products and castings in magnetic and non-magnetic materials, including glass, ceramics and plastics, again with tests carried out either in-house or on-site.

To enhance its ultrasonic testing facilities still further, Keighley Laboratories employs a Digital Flaw Detector, which incorporates current developments in amplifier and pulsar technology to deliver higher levels of near-surface resolution and penetrating power. It also uses a Magnetic Permeability Meter, for measurement of ferro-magnetic inclusions in feebly magnetic materials against relevant specifications, particularly for critical aerospace and nuclear energy applications, and a hand-held Ferrite Content Meter, for analysing the ferrite content in austenitic and duplex steel and testing weld seams and piping materials in the oil, gas and petrochemical industries.

Keighley Labs has achieved world-class Nadcap accreditation for a Materials Testing Laboratory and is approved by such bodies as Airbus, the UK Civil Aviation Authority, Rolls Royce and British Aerospace, enabling it to carry out sub-contract testing of aircraft and associated companies. It also meets the accreditation standards of many other customer industries.