The chemical industry is characterized by a multitude of processes in which corrosive, toxic and explosive media are pumped, stirred, transported and stored. Pumps and agitators equipped with mechanical seals for sealing the shafts are used to a large extent in all process steps. CHETRA takes into account these diverse application requirements as well as corresponding regulations (such as TA-air, ATEX, etc.).
Similarly, the pharmaceutical industry uses agitators, mixers and dryers to produce medicines and cosmetics in solid, liquid and paste form. For this purpose, CHETRA mechanical seals take special requirements into account: they are free of chemical and biological contamination, cleaning (CIP) and sterilisability (SIP) of the equipment without dismantling are also taken into account.
CHETRA takes into account the need for economic efficiency, compliance with legal requirements and environmental protection requirements right from the basic design of our seals and the selection of suitable accessories.
Extreme operating conditions and highest requirements
Innovative, often customized solutions based on decades of experience in the industry with well-founded application technology expertise.
Minimum abrasion due to the CHETRA Active Lub System
During granulation in tablet and powder production, vacuum dryers are used which rotate relatively slowly (approx. 5 – 30 min). In addition, their stirrer shaft changes the direction of rotation at short intervals. In most cases, these systems are operated with deionised water as a sealing medium for the double mechanical seal used.
Under these conditions, conventional, liquid-lubricated double mechanical seals squeal. This is an indication of the increased wear on the seal faces and the associated reduced service life and also a considerable noise nuisance. CHETRA’s specially developed Active Lub System prevents this lack of lubrication by supplying the optimum amount of liquid via appropriate feed zones and channels. The innovative Active-Lub System extends the service life of the mechanical seal.
New requirements for innovative plant concepts
In cooperation with a well-known European-American plant manufacturer CHETRA developed new highly sterile aseptic mechanical seals.
These are used in newly developed modular systems which cover the various applications of a mill, disperser, homogenizer and agitators.
The result of this development cooperation were two completely new mechanical seal types – 877 X and 900 S-aseptic – which allow easy replacement and meet the special requirements of the pharmaceutical industry in conjunction with the modular concept.
Customized solutions for existing plants
During the production changeover at the premises of an internationally active pharmaceutical group, a vacuum filter dryer was to be used to produce a new drug that removes excess iron from the body. For this production process a special adaptation of the mechanical seal was required.
CHETRA designed a gas-lubricated double mechanical seal (Type 577 G) with a bellows to absorb the axial movement: fully CIP and SIP capable using FDA-approved materials and “iron-free” steel parts in special alloy. In addition, the mechanical seal was adapted exactly to the existing conditions, so that a problem-free conversion to the new seal was possible.