The sensors in DELTATEST are robust and simple, and mainly of the rotating type.
The sensors are differed by the mechanical design costumized for each application. Due to the abcence of sliprings and similar, the mechanical lifetime is normally only limited by the durability of the rotor-bearing.
To achieve maximum operation reliabilty, it is necessary that the surface scanning by the sensor is made contact free and with an acceptable air-gap (LO) between the sensor and the test surface.

The rotating type of surface scanning sensors in the DELTATEST system, can be divided into two main categories:

• Type P: The sensor coil is rotating in a plane parallel to the surface of the sample.
• Type R: The sensor coil is rotating around the periphery of the sample.

The P-type sensor is used for plane and round surfaces/objects.
You can for example arrange type P-sensors in a star-shaped formation around bars, rods, tubes etc, and by this scan the whole circumference. By letting the tracks overlap each other in a fine-meshed scanning pattern, you can detect short as well as long cracks, no matter their orientation.

The type R sensor is mainly designed for crack detection on thin, rounded samples, for example wire,rods and thin tubes, and is combined with a so called "feed through sensor" when necessary.

Preliminary data for type R sensor:

More about non-rotating sensors + pictures:

• Non-rotating for flat surface
• Non-rotating for round surface
• Oscillating

More about rotating sensors + pictures:

• Rotating for both flat and round surfaces
• Sensors in a star-shaped formation
• Surface scanning pattern