The SZM type glass tube level indicator is applicable for the indication of liquid level in small and middle-sized, standing or lying round containers used in food, pharmaceutical and chemical industries. The loads occurring at the installation are absorbed by the outer armature, thus the glass tube is protected against breaking.
The outer armature also protects the glass tube against the mechanical impacts that may occur following the installation. It is recommended that the normal design level indicators be fitted on vessels containing pure liquids, while the indicators mounted with cleaning stubs (a bottom, or bottom-top stub) be fitted on containers filled with contaminated liquid.
Installation length means the distance between the horizontal centre lines of the two fl anges, that is minimum 370 mm, and maximum 3 080 mm. The glass tubes longer than 1 500 mm are welded. The bottom, and top sealing of the glass tube is by two O-rings each, the material of which is to be chosen to be chemically compatible with the liquid measured.
Standard sealing material is FPM, whereas EPDM or NBR are available on request. The level indicator may be furnished with capacitive level sensors - max. 3 pieces over 100 mm - as requested (NAMUR design), which monitor the minimum and/or maximum level or any level along the scale.
Anodised aluminium rule with indication of level or volume may be mounted optionally on side of the outer armature. The scale can be engraved on the aluminium rule or the glass tube, or can be printed on a foil and to be attached to the glass tube or aluminium rule.