Dry-running single-acting mechanical seals are designed for sealing of gas blanket (top drive) of mixers and agitators. These mechanical seals has been fully proved and are economical by omission of double-acting mechanical seals and expensive supply systems. These mechanical seals are multi spring, externally mounted, balanced and independent of direction of rotation. In pharma, bulk drugs, food, and beverage industries mixing of any other liquid will contaminate the product hence these dry running seals are used. Various face materials & elastomers are offered to cater wide applications. Solid non-shrunk seal rings/ stationary seats with corresponding seal face geometry provide stable conditions at the seal faces, even with higher temperatures or temperature variations, ensuring low wear operation and long service life.