Emerson Rosemount CT4215, Reference Manual

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2.9 Sample head types
Sample heads are used in conjunction with the leak detector to identify packaged
products that have a break in the seal integrity as they are carried along a conveyor belt at
speed. Sample heads draw air from around the product through a measurement cell in the
leak detector. Continual analysis of the sample air will then detect and identify packages
with defective seals.
2.9.1 Passive roller
The passive compression roller is a non-powered variable height sample head used to
apply a gentle squeeze to packages to encourage Modified Atmosphere Packages (MAP)
gas to leak through defect points. The sample head height can be height adjusted on the
production line to support multiple product pack sizes.
A. Sample bar.
B. Roller.
C. Height adjustment.
The passive roller head consists of three semi flexible rollers with sample bars fitted at the
entry and exit of the sample head.
As product packs pass through the passive roller head they are compressed by the roller
material flexing. The roller is free to rotate as the packages travel along the conveyor.
The roller height can be adjusted to set the compression being applied to the packages
being run at that time.
Reference Manual Equipment and accessories
00809-0100-4245 July 2022
Reference Manual 25