Spectrum Spider Wheel

The Spectrum Spider wheel is designed to integrate standard NIR, UV, Raman and Particle size analyser probes into moving powder streams, progressing down transport chutes or exiting processing equipment into a pipe or hopper The device is a rotating wheel with various shapes of fingers, that rotate within the powder stream, capturing powder over the probe window mounted on the top side of the spider wheel. The fingers are designed to systematically control collection of a sample from a moving powder bed such that a good PAT measurement may be made. The fingers of the spider wheel are designed to capture an optimal amount of sample to be scanned over the window of a probe, then move that sample onwards down the chute or pipe, at the same time, wipe the probe window ensuring fresh sample replaces the scanned material over
the probe.

The underside of fingers of the spider wheel are lined with a PTFE layer, which eliminates the light reflected off the bare metal of the fingers, which would otherwise add significant noise to the spectra collected by the spectrometer probe.

There are a range of sizes of the spider wheel depending on required flow rates of the sample stream. The spider wheel base can be heated to reduce the possibility of material sticking to probe window or the device itself. The device is constructed from fully traceable and certified FDA approved materials of construction. Air actuation of the device allows safe use of the Spectrum Probe Holder in ATEX Zone 21/22 process environment.


  • Contact materials: 316L stainless Steel, highly polished
  • Pressure rating: 10 Bar max.
  • Diameter range of probes that can be accommodated 12- 32mm
  • Probe lengths between 200 – 300mm can be accommodated
  • The holder has internal heating in the range ambient to 80 degrees C


  • This spider wheel is particularly good for powder streams moving down a chute or pipe
  • Material exiting equipment like a mixer, granulator or mill
  • The interface can be used with continuous processes or when off-loading batch processes