Different Types of Mechanical Seals

Seals play an essential part and act as a component in the System of centrifugal pump. It prevents leakage of fluids and makes sure that the impurities do not enter the System.

Mechanical seal systems work in various ways to spot the leakage, oil the secondary seal, and ensure that the sealed environment is controlled. There are many kinds of seals available these days due to their exceptional uses. But the seal entirely depends on the type of pump you use for the machinery.

Every seal has their distinctive character and design for them to work. Cheshire Seals and Components Ltd. It has varieties of functional machine seals which use commercial design software for their application.

Below are some of the most common kinds of seals used in machinery and some seal details.

Balanced seals

The balanced seal system works by balancing the forces that act at the seal faces. When the loading of the lower face is flat, there is more lubricant, and seal life lasts longer. It is essential that the seal faces are balanced; otherwise, the liquids squeezes out and may cause the undesirable condition.

Unbalanced seals

Unbalanced seals are more economical than balanced seals. The seal is vital to hydraulic closing force when it amounted to pressure than two face seals. So they provide significantly fewer leakage problems. But if too much closing force is applied on the seal face, then the seal cannot withhold the pressure limit, which results in squeezing out the lubricating film. In all, the unbalanced seal cannot exert too heavy a load and is not recommended for hydrocarbon applications. The seal life is also significantly less as compared to a balanced seal.

Conventional seals

Conventional seals are mainly used for general service equipment. They are also low on cost and simple to use as compared to other seals. However, the seal must be appropriately aligned and set on the pump shaft or sleeve before using it. Though they are simple, the seal needs skilled installation service.

Cartridge seal

The significant advantage of the cartridge seal is that they do not need a service installation setting like that of conventional seals. Thus, it greatly helps in reducing the maintenance required and lessens the errors to occur during the stage.

Pusher seal

The seal uses different springs to keep the closing force of the seal. The spring of the seal either rotates or stays as a stationary element. It can seal the machinery at very Hugh pressure as well. The pusher seals are less expensive, commonly used, and readily available in the market.

Non-pusher seal

The non-pusher seals are also known as bellows-type seals. The seal does not have to essentially move along the shaft or the sleeve compared with the pusher seal to maintain contact with the seal’s face. Non-pusher seal can ideally work under applications of high pressure and low temperature. In case of works under corrosive environment, the bellows need to be upgraded.