The main reason for leakage by sealing parts

The leak is one of the common faults of machinery and Reinforced Graphite Gasketequipment. The cause of the leak has two aspects: Problems First, the mechanical processing, mechanical surface of the product must exist for the various defects and the shape, size deviation, therefore, at the connection of the mechanical parts will inevitably produce a gap; Pressure difference on either side of the seal, the working medium will leak through the gap. Eliminate or reduce any - Due to tangled can stop the leak. The sealing effect is to air seal the joints between isolated or cut off the leakage path, increase the resistance of the leakage path, or the additional small acting components in the channel. On spilled material pressure, part of the leakage caused by the pressure difference offset or balance, in order to prevent leakage. Sealing of the vacuum system, in addition to the sealing medium directly through the sealing surface leakage, but also consider the following two forms of leakage.

(L)) leak. I.e. under the action of the pressure differential, the medium to be sealed by capillary leakage of the seal material is called leakage.

(Z) diffusion. I.e. under the action of the concentrationMetal Jacketed Gaskets difference, the medium to be sealed through the material of the sealing gap or the sealing material of the capillary pass called diffusion customary referred to as "sealing material outgassing in the vacuum system. First, the sealing member is absorbed by adsorption gas, and the gas diffusion in the sealing member, is precipitated from the other side of the sealing member.

The amount of leakage of the vacuum sealing with the form of sealing, the sealing material, the sealing surface machining accuracy and assembling quality factors.

The effectiveness of the sealing effect of "tightness" to measure. Tightness can be used per unit of time within the volume of the medium or the quality of the amount of leakage, i.e. the leakage rate. The seal leakage zero Ideally referred to as a "zero leakage". Generally, static seals may reach zero leakage, the movable seal, due to contact with the sealing surface of any relative displacement will create conditions for the engagement of the surface roughness on the leak medium, it is particularly difficult to achieve zero leakage. Often critical sealing requirements engineering tightness allowable value.

Sealing performance is an important indicator to assess mechanical product quality through. The working medium in the apparatus or the leakage of the lubricant, Wasteful and polluting the environment, flammable, explosive, toxic, Raw Materialscorrosive, radioactive substances leak would endanger personnel and equipment safety, the environment of gas, dust and water from entering the bearings, gears and other machinery and equipment will result in wear out prematurely scrapped leak into the chemical plant will affect the purity of the chemical products' within the fluid mechanical leak will affect the volumetric efficiency. Chemical enterprises in the continuous production of seal failure is the main cause of unplanned shutdowns. According to statistics, 60% write of unplanned shutdowns accident with seal failure.