Many industries are choosing to use UV lamps for non destructive testing to great success. For many reasons, they’re an ideal means of performing routine and spot inspections. Before purchasing this type of equipment, however, it’s best to review things to look for in a quality UV lamp, how to find suppliers, and which UV lamps are amongst the best for industrial use.
Overview of UV Lamps for Non Destructive Testing
Most inspection processes that rely on consistent and accurate results from NDT realise the benefits that UV lamps bring. Not only ere UV lamps used by engineers and inspectors to cut production costs by identifying defective parts or components on assembly lines, they are also a safer option as well since testing takes place simply with light.
LED Lamps vs Incandescent/Fluorescent Bulbs
Historically, NDT testing with UV lamps was done with mercury-vapour and micro-discharge technologies that have become all but obsolete. There are many disadvantages to these when compared to LEDs.
Incandescent and fluorescent bulbs may be dangerous and thus pose a safety hazard for employees due to their sheer weight and the processes often involved with bulb and filter replacement. Furthermore, these bulbs are being replaced by LED at a rapid pace, so it may become more and more difficult to find and purchase bulbs going forward.
LED lighting technology has proven itself to be superior to incandescent and fluorescent bulbs for quite some time now, so it only makes sense that NDT methods have been improved by LED as well. Specifically, high-intensity UV-A lights – both fixed and handheld – have made waves in NDT for a number of reasons.
Consequently, high-intensity UV-A lamps powered by LED technology are a cost-effective, safe, and efficient means of conducting NDT in most industrial applications. They have superior illumination, release less heat, have a far longer bulb lifespan, and boast a much lower fade rate.
Things to Look for in a Quality UV Lamp
Not all UV lamps are created equal, so it pays to understand some of the key components in order to select the correct product for your particular application.
Peak Wavelength
The most important consideration for a UV-A lamp is its peak wavelength. In former times, mercury-vapour was (and sometimes still is) used for NDT penetrant and magnetic particle testing. Mercury’s elemental emission line was thus used in the formulation of testing products and therefore produces fluorescence under UV-A lighting at 365 nm. For this reason, an LED UV-A lamp needs to achieve a peak wavelength between 360-370 nm.
For reference, the UVA light spectrum is between 315-400 nm.
Emission Spectrum
Fluorescent testing methods often take place in the dark, whereby light shedding in from the outside can interfere with the quality of the inspection. Since UV-A emitted by LED technology produces a wide spectrum, the tail end tends to produce a visible violet glare that is undesirable at best and unacceptable for more demanding applications, such as aerospace part inspection. A UV-A pass filter will block these emissions and is therefore preferable on a quality UV-A lamp.
Beam Area
If the lamp produces too wide or too focused a beam for its specific application, results will be skewed and inconsistent. Always pay attention to the recommended working distance and select a lamp that produces the correct coverage for the part or component to be inspected. Furthermore, choose a lamp without hot-spots in the beam profile, as this can lead to a sort of ‘tunnel vision’ whereby irradiated areas outside of the focus area are not inspected properly.
Power Supply
For portable, handheld lamps, power supply is a critical concern since the device’s LED intensity will diminish proportional to the voltage and current. Requirements stipulate that 1,000 μW/cm2 is the bare minimum intensity, so ensure that your desired lamp is capable of exceeding this minimum intensity during daily use. Moreover, ensure that the lamp contains a circuit that monitors the discharge of the battery and is capable of shutting off whenever the minimum intensity cannot be achieved.
International Standards
Requirements and tolerances for NDT with UV-A lamps depends on the industry and the application, but in all cases a quality lamp should meet international standards for NDT methods. Industries such as aerospace manufacturing understandably have much higher standards, so they’ve produced requirements for UV-A testing with ASTM E3022. Although most other industries don’t need to meet this standard, a product that does will naturally get nearly any job done to this high standard.
Additional Considerations
All of the above factors are of major importance when looking for a quality lamp, but the following factors should also be considered:
- Comfort: for handheld devices, technicians should be using lamps that are light enough not to cause discomfort through routine daily use;
- Operating temperature: older bulb technologies can run hot, posing a workplace hazard. LEDs tend to run much cooler, but can still heat up significantly. Look for a lamp that runs at an acceptable heat level for its application;
- Energy consumption: UV lighting is energy-intensive, which is an expense that adds up over time. LEDs consume far less energy, but some lamps are better at reducing consumption than others;
- OEM certification: if the original equipment manufacturer can provide certification, it can give peace of mind to operators and inspectors knowing that the equipment meets or exceeds standards with official certification to back it up;
Benefits of Handheld UV Lamps
Many modern plants and production facilities use handheld UV-A lamps either in conjunction with angled overhead lamps or on their own. Here are a few reasons why handheld UV-A lamps are an ideal asset for NDT professionals:
- It’s a non-toxic method of testing that doesn’t rely on chemical compounds;
- Accelerate inspection times by quickly and conveniently performing spot inspections;
- Achieve greater flexibility for areas that may not be easy to reach with overhead or fixed UV-A lights;
- Lightweight and portable;
- Cost effective due to the prevalence of LED technology and improvements in battery technology in recent decades;
- Can be safer, since many phosphor and mercury-vapour incandescent and fluorescent bulbs and fixed lights can pose a safety hazard.
Handheld lamps are ideal in recent years due to all of the above benefits. In cases where the demands of high production facilities require high-quality, cost-effective NDT methods, such as at an automotive facility, handheld lamps have proven to get the job done exceptionally well.
UV Lamp Suppliers
Not all UV-A lamps are created alike; differences in quality can range from acceptable to potentially disastrous. Therefore, it’s essential that industries spend the time to find quality suppliers that have a demonstrably good track record of success and a strong reputation over the years. Magnaflux is a leading innovator and producer of high-quality NDT products, and they’re no slouch when it comes to UV-A lamps.
NDT products from Magnaflux are used in many industries, including aerospace, which indicates that their quality is certainly acceptable for the highest of standards. Cotter Marketing is proud to carry products from Magnaflux that can help plants and production facilities achieve the highest levels of NDT and thereby improve quality and reduce defects.
Partnership with Cotter Marketing
NDT products and equipment from great suppliers such as Magnaflux can be acquired within Ireland through Cotter Marketing, an industry leader in NDT and industrial products and equipment. Consider partnering with Cotter Marketing to gain access to high-quality products that can improve the operating efficiency of your plant or production facility. Below are some products that are available through Cotter Marketing or one of our trusted suppliers:
EV6000 Hand-Held LED UV Lamp
The EV6000 LED UV Lamp is one of the best handheld LED UV-A lamps available on the market for a variety of reasons, including:
- Effective: wide, even beams of evenly-distributed irradiated light clearly show surface indications even at the fringes of the 23 cm beam;
- Speed: reduces testing time significantly due to its superb beam width and intensity;
- Adaptable: can be used for nearly any type of inspection with fluorescent penetrant or magnetic particle inspection;
- High standards: acceptable for use with aerospace parts as it meets ASTM E3022;
- Durable construction: built to withstand the rigours of daily use thanks to an IP65-rated housing.
Note that the EV6000 complies with the following standards: ASTM E2297, ASTM E3022, ISO 3059, ISO 9934-3, RRES 90061.
Non Destructive Testing at Cotter Marketing
Liquid penetrant testing, magnetic particle inspection, and UV lamps all fall under the domain of non destructive testing methods for which Cotter Marketing can provide products and expertise to industry professionals.
With over 40 years of industry experience, Cotter Marketing proudly serves industries across Ireland as varied as pharmaceutical, biochemical, marine, oil and gas, medical, food and beverage, and many more. Contact Cotter Marketing today to learn about how we can help your plant or production facility operate more safely, efficiently, and cost-effectively.