
Designed for close-to-structure inspections, Voliro‘s advanced Voliro T drones enhance non-destructive testing (NDT) processes by gathering more detailed data in less time, inspecting assets while in use to prevent unnecessary downtime and production delays.
NDT refers to a set of techniques used for inspecting materials, components, and assets without compromising their integrity. These methods are essential for quality assurance and examining materials in various industries.
Industrial assets such as oil storage tanks, lightning protection systems on wind turbines, pipes, and supporting pylons need regular inspection for both maintenance and regulatory reasons. NDT inspections identify defects, flaws, irregularities, or signs of wear to ensure the safety and durability of these structures.
Non-destructive testing is the only method to obtain detailed material characteristics of an asset while preserving its condition. The most commonly used NDT techniques rely on sound waves, acoustic impulses, or gamma rays to assess materials. By combining various methods, NDT technicians can detect tiny cracks, voids, or weld inconsistencies that are not visible to the naked eye.
With 360-degree mobility, Voliro drones allow teams to safely conduct inspections at heights and in confined spaces. AI-assisted autonomy, along with three days of pilot training included with every subscription, ensures using a Voliro drone is as straightforward.
Destructive vs Non-Destructive Testing
Destructive and non-destructive testing both assess material endurance but operate on different principles. NDT aims to preserve the integrity of the material, while destructive testing (DT) subjects the material to extreme conditions, such as high temperatures or heavy loads, until it deforms or breaks. Destructive tests help identify the material’s breaking point, while NDT provides valuable data on the asset’s condition, quality, and reliability.
The frequency of NDT inspections depends on the assets in use, as established by regulatory bodies and certification organizations such as SAFed, IoP, or ASNT. Even when NDT is not a direct requirement, performing regular inspections is often more cost-effective than replacing equipment entirely. Asset owners create NDT schedules based on the risk level of their assets and industry standards to avoid unexpected downtime.
Visual Testing (VT)
Visual testing (VT) involves inspecting the surface of a test object for any discontinuities or damage. Remote visual inspections are effective at detecting corrosion, physical damage, misalignment, and cracks, especially in hard-to-reach areas.
NDT technicians use VT as a standalone method for identifying visible damage like poor welds in oil pipelines or cracks in storage tanks. With tools like the Voliro drone, technicians can inspect 8-10 storage tanks in a single day for signs of wear and tear, utilizing UT and EMAT payloads.
VT is also a precursor to other NDT methods like ultrasonic and radiographic inspections. It helps identify areas of interest and ensures the surface is free of contaminants, coatings, or obstacles that may interfere with subsequent tests.
Ultrasonic Testing (UT)
Ultrasonic testing (UT) uses high-frequency sound waves to inspect assets. When a sound wave encounters an irregularity, part of the wave bounces back, signaling the presence of a potential defect. This method is akin to using sonar to detect fish but is aimed at locating flaws within materials.
UT utilizes different types of sound waves, including compression waves (vibrating in the same direction as the sound) and shear waves (vibrating perpendicular to the sound). Compression waves are used to detect parallel surface cracks or fractures, as well as voids or porosity in the material. Shear waves are typically used to detect laminations or delaminations (separation of material layers), and inclusions or foreign materials within the asset.
UT can be used to detect weld problems in structures, pipelines, pressure vessels, and tanks, as well as corrosion, erosion, and wall thickness issues in piping systems. It is commonly employed to detect early signs of wall thinning, pitting, or stress corrosion cracking in pressure vessels and storage tanks.
Ultrasonic testing is typically performed with handheld transducers or probes, which can also be mounted on drones to reach tight spaces or elevated areas. Using drones for UT inspections reduces risks and eliminates the need for personnel to access high or difficult-to-reach areas.
Voliro has developed specialized ultrasonic transducer payloads capable of live scanning at temperatures up to 260°C (500°F), greatly reducing the time and effort needed for data collection.
Voliro drones are capable of conducting thorough inspections in challenging environments like chimneys, storage tanks, or stacks. UT inspections can often be completed in a single day without needing to shut down operations.
Eddy Current Testing
Eddy current testing is an electromagnetic inspection method for conductive materials, including metals, alloys, and conductive coatings. Unlike magnetic particle testing (MPT) and liquid penetrant testing (LT), it does not require direct contact with the surface.
This technique applies an alternating current to generate a magnetic field, inducing eddy currents within the material. Variations in the current’s pattern indicate flaws or defects, allowing for precise detection and analysis.
Eddy current testing is a reliable and cost-effective solution for quality assurance and safety inspections of power cables, heat exchanger coils, condenser tubes, non-pyrogenic alloys, and carbon fiber composites. It is the preferred non-contact method for inspecting conductive materials.
Voliro is introducing a new PEC (Pulsed Eddy Current) payload capable of detecting early-stage CUI with up to 100 mm of insulation thickness.
Other NDT Methods
NDT utilizes a variety of techniques to assess materials, components, and large structures. Other primary methods include:
- Magnetic Particle Testing (MPT)
- Magnetic Flux Leakage Testing (MFL)
- Liquid Penetrant Testing (PT)
- Radiographic Testing (RT)
- Acoustic Emission Testing
- Ground Penetrating Radar (GPR)
- Guided Wave Testing
- Thermal/Infrared Testing (IR)
- Microwave Testing (MW)
- Laser Testing (LM)
- Leak Testing (LT)