Mechanical Seals Components Supplier

The seals do not have to fit in narrow seal cavities initially intended for glands. In other words, it must be able to slightly alter its position in order to adjust to small shaft deflections and face wear during operation of the unit. The seal will not be tight unless the seal faces are flat, and remain flat during operation. Mechanical Seals do not depend on rubber friction for the transmission of torque between shaft and seal ring. The closer the gap between the two surfaces, the less the leakage.. Because there is friction between the mechanical seals faces, there will also be torque transfer. The static seals, which are usually made from some kind of rubber, form a stationary mechanical seals around the seal rings. Consequently, a well made mechanical seals both fulfills its primary function of preventing leakage, and also has a long service life.

A stable and symmetric design is necessary in order to attain a flat mechanical seals faces. Therefore, one of the two faces is made of carbon, which exhibits very good sliding properties, though relatively low wear resistance. The face load is decided by two parameters the force exerted by the spring the "balancing ratio" The spring load, if it is to keep the seal tight, must be high enough to overcome dynamic forces and the friction force from the semi-dynamic static seals. The best way to prevent this happening is to "anchor" the rings as firmly as possible to their retaining structures. However, hard-faced inner seals are available where extra protection against abrasives is required.

There is consequently little room for variation in the spring force. If the pressure closing the two faces becomes too high, the Sealing Ring Manufacturer area of direct contact between will be too large and the mechanical seals will seize. This enables seal rings, springs and O-rings to be adequately seized and seals to be made short, as the components do not need to be piled on top of each other. The position of this critical load point for each mechanical seals, depends on the face material, the balancing ratio and the ability of the particular seal;s design to dissipate heat. The ratio is the proportion between the outside area of the mechanical seals ring (on which the pressure of the external liquid is exerted) and the area of the actual seal face. The main components of a mechanical seals are two seal rings a spring two static seals and a torque locking system. These contaminants might otherwise form deposits, which could jam or damage the seal. At the same time, the spring load must not be so high as to cause unacceptable levels of wear and heat generation. If mechanical seals faces are not flat, then the mechanical seals will leak, regardless of all other parameters. Being free from this limitation, seal designs can utilise radial space for its components. Even so, a partial liquid film is created between the smooth, flat faces. This facilitates both assembly and dismantling. The flatness of the mechanical seals ring faces is the crucial factor determining the effectiveness of a mechanical seals. This can cause the face which is supposed to be stationary to rotate in its housing, and the rotating face to become detached from the shaft.

They are necessary to prevent leakage at the joints between the seal rings and their retaining structures. The oil in the compartment between the mechanical seals has three major functions; lubrication, cooling and emulsification of leakage. The size of this ratio is determined by the design of the seal. The mechanical seals faces have no macroscopic hydrodynamic features, such as grooves or steps, which would inevitably generate a liquid film. The inner seal is subject to less abrasion, as it is protected by the oil compartment. The balancing ratio is therefore the main factor determining how much pressure a mechanical seals can take. In addition to this, flat, parallel faces are not only crucial for preventing leakage, they also prevent abrasive particles from entering between surfaces of the mechanical seals. The static mechanical seals positioned around the spring-loaded face is often referred to as "semi-dynamic". The basic lay-out of the sealing system is the same on all Flygt products; an outer mechanical seals, an oil-filled chamber and an inner seal. Outer and inner seal operate independently of each other. The lubrication regime between the faces is known as a "mixed lubrication".The principle of the mechanical seals is quite simple: Two flat, ring-shaped surfaces, one stationary and one rotating, are pressed together so as to create as narrow a gap as possible between them. This can be achieved either with mechanical devices, such as pins, socket screws or washers, or by simply exerting pressure around the ring, usually by compressing the static rubber mechanical seals. Short seals means that the drive shaft can be made short. A short drive shaft minimizes impeller deflections and bearing loads, thus enhancing both the performance and service life of the product.

The spring preloads the faces, ensuring that they are in constant contact, even when the mechanical seal is not under pressure. With higher face loads the area of liquid film decreases and the direct contact area increases. The lubrication and cooling functions are fairly self-evident: Without the oil the seal faces would rapidly overheat and seize. During operation, though, the dominant closing force, pressing the faces together, is the pressure exerted from the sealed liquid. Its faces are made from abrasive resistant materials, such as cemented carbide, silicon carbide or aluminium oxide. This means that, as surfaces move across each other, there is a mixture of a liquid film and direct contact between them. The outer seal is the more refined of the two seals. Instead there is a always a mechanical device which ensures a positive drive. The emulsification function involves diluting and suspending liquids and particles which may leak through the seal. Because static rubber mechanical seals are not required to serve as torque locks, they do not need to be clamped so tightly. This is somewhat more costly but far more reliable