Optical and thermal imaging

HENSOLDT’s long-range thermal camera, mainly developed for space and defence applications, brings unrivalled results to the blade inspection market. Optical (visual) imaging technology can identify flaws on the blade surface. Yet internal structural flaws such as delamination, wrinkles in the spar, or bonding issues can be detected only by thermal inspection methods.

 

Inspection Methods

 Rope access

HENSOLDT’s solution

Optical

Thermal

Pollutionyesyespartially
Leading edge erosionyesyesyes
Visible on surfaceyesyespartially
Crack caused by fillernonoyes
Crack caused by blisternonoyes
Crack caused by wrinklenonoyes
Delaminationpartially (tapping)noyes
Trailing edge bondingpartiallynoyes
Beam to shell bondingnonoyes
Vortex generatoryesyesyes
Resin channelnonoyes
Dry laminatenonoyes
Internal humiditynonoyes

 

The combination of both optical and thermal images can cover a wider range of flaw types. A second inspection is not required, as the images are reproducible and objectively reflect the condition of the blade.
This method was rated as being equivalent to the rope access method by the certification body DNV GL.

Cutting-edge thermography

A cooled high definition thermal camera is used with a very small noise equivalent temperature difference (NETD) of 0.025 kelvins. The camera lens has an aperture of 25 cm and the focal length of the system is equivalent to 4,000 mm (calculated to small image format).

HENSOLDT’s technology is based on a cooled mid-wave detector (3.5–5 µm) to achieve the best performance for the thermal images, capturing thermal data with a pixel thermal resolution of 14 bits in the current range.

The use of optical and thermal high resolution camera systems with large focal length is the key to providing high quality imaging.

Lower costs at minimal risks

HENSOLDT optical and thermographic inspection from the ground poses minimal Health, Safety and Environment (HSE) risks with almost no loss of energy yield. There is no risk of turbine damage, accidents or physical injuries.

We offer cost advantages and more flexibility for all parties involved:

  • Lower downtime: one single operator scans the four sides of all three blades within 60-90 minutes from the ground
  • Less weather restrictions: blades can be inspected in cold weather and marine environments
  • Minimal HSE risk: no concerns of damaging the turbine or of physical accidents during the inspection

Records during the blade’s entire life

Images from blade commissioning, past inspections and previous repairs can be compared from year to year and recorded during the blade’s entire service life.

Service-life data records and fatigue evaluations are especially useful for periodic inspections and are essential in the decision-making process to extend blade lifetime.

Repairs can be better scheduled, avoiding short-notice repair actions, and also more precisely performed and monitored.