Published on 11-Aug-2023

The Power of Foresight—Videoscopes Help Improve the Quality and Efficiency of Steam Turbine Inspection

The Power of Foresight—Videoscopes Help Improve the Quality and Efficiency of Steam Turbine Inspection

Nuclear power is part of many countries’ energy strategies to reduce greenhouse gas emissions and the overall costs of power generation. In many cases, the efficiency and service life of older nuclear power plants can be improved by increasing the efficiency of the steam turbine system, including the steam channel. There are two ways to do this—overhauling the turbine, which entails shutting it down and repairing or replacing damaged components, and improving the system’s design, such as developing a new blade profile or turbine structure. In either case, it is essential to inspect the system and assess its condition.

Visually Inspect In-Service Components with RVI

Older turbines typically require periodic overhauling, which is a complex and time-consuming process. The condition of the turbine determines whether a minor or major overhaul is required, so it’s important to monitor it for deposit accumulation and damage. Steam turbines are subject to temperature changes, moisture flow, vibration, etc., so they are susceptible to a wide array of internal defects, including bruises, scratches, deformation, edge curl, pits, breach, material loss, and cracking. A reliable and unobtrusive method for detecting these defects is remote visual inspection (RVI) using a videoscope. Owning an industrial videoscope gives nuclear power plant operators a powerful tool to optimize their maintenance plan by enabling them to see parts that are inaccessible using other methods.

Our IPLEX™ GX videoscope is currently used in nuclear power plants to internally inspect complex parts such as turbine blades, as it is easy to operate, even by novice users. The complexity and conditions of turbine-blade inspection necessitates high image quality and illumination, a wide field of view, and highly responsive scope tip articulation so you can navigate around the blades with ease.

For this application, we recommend a configuration including the IPLEX GX videoscope with two 6 mm diameter insertion tubes and an optional stereo-measurement dual lens scope tip—in addition to the standard single lens tip—to enable you to size defects using precise 3D coordinates.

Crisp Images, Portable Touch Screen

A videoscope is only as good as its screen—there’s no point using advanced lenses if the on-screen image quality is poor. The IPLEX GX videoscope has an 8-inch wide-angle color touch screen that offers 170-degree visibility for easier viewing from different angles. Using the touch screen is simple and straightforward, so all functions can be performed quickly. It has a resolution of 768 × 576 pixels or higher, and the brightness adjusts automatically to maintain a crisp, high-definition image in just about any lighting condition.

Recording what you see is also critical for record keeping and comparing changes in a component over time. The IPLEX GX videoscope’s 60 frames-per-second (fps) video recording can clearly display rotating turbine blades without any delay. Compared with standard 30 fps images, the IPLEX GX videoscope’s frame rate makes observation smoother. Its dynamic pulse lighting system combined with the gain function produces a clear and evenly lit image, which is particularly useful for complex metal structures like turbine blades that can reflect light.

Acquire Quantitative Data with 3D Stereo Measurement

Stereo measurement can help an inspector quantitatively analyze the position of detected defects. When equipped with a dual lens scope tip, the videoscope’s three-dimensional measurement function enables the inspector to precisely place points on the touch screen to measure the area, perimeter, depth, length, and other dimensions of the target, down to a 0.01 mm accuracy. The measuring lens has a field of vision of more than 60°, and it is equipped with a dual optical path system.

Withstands the Tough Demands of In-Service Turbine Inspection

The videoscope’s casing is sealed with industrial-grade rubber, and the internal electrical components are well protected as the unit is IP65 waterproof and dustproof certified. It is also 1.2-meter (4 ft) drop tested and passes the US MIL-STD verification.

The long and short insertion tubes can be easily switched on site, so the long tube can be set aside safely to avoid winding or trampling. You can also prolong the service life of the insertion tube with the five-layer tungsten woven sheath, which stands up to more than 100,000 uses. It resists harsh environments and can be used in water and oil. For more ways to preserve the life of your videoscope insertion tube, check out these additional tips.

The oil clearing tip adaptor can be used to prevent oil adhesion on the lens. The tip’s rugged and reliable titanium alloy material uses capillary action to remove oil and water. The responsive TruFeel™ tip articulation can be controlled using the joystick or the touch screen, so it can reach the target with ease, even when faced with the multiple bends and angles of turbine blades.

Allocate Your Maintenance and Overhaul Plan More Effectively

The defects and hidden dangers of turbine blades can be identified in advance when you use a videoscope to regularly inspect inside the steam turbine. It can effectively reduce or help you avoid the unplanned failure of metal parts and improve the safety and stability of steam turbines, helping ensure safe production at nuclear power plants. The Olympus IPLEX GX videoscope features rugged, interchangeable insertion tubes and light sources, a bright 8-inch touch screen, and advanced imaging functions, achieving a balance between versatility, imaging ability, and ease of use.