The HPLG, Henkel Passive Layer Guard, is an inline monitoring system which diagnoses the process of depassivation and the subsequent formation of rouge.
This system enables the operators of water systems to recognize changes on the surface online without opening the system.
With the assistance of the HPLG the passive condition of a tube system can be recorded. The operater is informed in time in order to schedule reconditioning measures (derouging and repassivation) for defined surface conditions.
The point of time when particle emission begins can be predicted thus optimizing the budget for maintenance measures.
The installation standard of the HPLG depends on the dimension of the tube system. The measuring sensor is approximately 200 mm long and can be supplied with any standard clamp connection.
Working principle HPLG 
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