Wipers and washing when the medium fouls the glass
When fouling makes observation impossible and how wipers and washers are arranged.
Short answer
If the product sticks to the glass, observation is lost between washings. The solution is a wiper (mechanical) or a washer (medium flushing), chosen for the fouling pattern.
The flushing medium must be compatible with the product and the fitting; introducing it changes the process and requires the designer verification.
Two approaches
A mechanical wiper periodically wipes the inner glass surface from outside the fitting. A washer feeds a flushing medium onto the window. The choice depends on the product: viscous sticking — mechanics; dust and light deposits — flushing.
What to verify
Both devices add a penetration into the wall or the fitting body — this affects the construction and compatibility:
- compatibility with the body of the specific fitting;
- the material of the working parts versus the medium;
- pressure and flow of the flushing medium and its compatibility with the product;
- the effect on hygienic requirements (dead zones, washing).
Typical mistakes
A washer does not replace the choice of glass material: an aggressive flushing medium changes the operating conditions of the whole pack. Agree it with the vessel designer.