Classification and Installation of Gaskets
Definition of Gasket
Pad is two mechanical seals between objects, usually under pressure between two objects that prevent, the leakage from naturally expanding with heat and contracting with cold burn into and pipeline. Since machined surfaces can never be perfect, irregularities can be filled with shims. Gaskets are usually made of sheet-like materials such as paper pads, rubber, silicone rubber, metal, cork, felt, neoprene, nitrile rubber, fiberglass, or plastic polymers such as Teflon. Gaskets for certain applications may contain asbestos. the
A spacer is a hole in a thin plate that is usually used to distribute load-threaded fasteners. Other uses are spacers, springs, wear pads, pre-display devices, and lock devices. Rubber gaskets are also used in valves to cut off the flow of liquid or gas. Rubber or silicon gaskets can also be used to reduce fan vibration. Usually, the outer diameter of the gasket is about twice the inner diameter. An overhaul gasket can be found in engine repair parts.
Material Classification of Gaskets
The gasket is a part between the connecting piece and the nut, generally a flat metal ring. the
Non-metallic gaskets are gaskets made of non-metallic materials such as asbestos, rubber, synthetic resin, and polytetrafluoroethylene. The non-metallic coated gasket is covered with a layer of synthetic resin and other non-metallic gaskets. Semi-metallic gaskets are gaskets made of metal and non-metallic materials, such as wound gaskets and metal-clad gaskets.
a Wound gasket is a gasket formed by helically winding a metal strip with a V-shaped or W-shaped cross-section to clamp a non-metallic strip.
- The inner ring is set on the metal ring of the inner ring of the wound gasket.
- The outer ring is set on the metal ring of the outer ring of the wound gasket.
b metal cladding
Metal gaskets Gaskets are made of metals such as steel, aluminum, copper, nickel, or Monel. the
A wound gasket refers to a gasket that is wound with a metal strip and a non-metal strip to form a ring. The metal strip and non-metal strip are alternately wound. Because of its good elasticity, it is widely used in flange sealing in petrochemical, chemical, electric power, and other industries. In the structure, according to the specific position, a steel ring can be added to the inner or outer layer of the gasket for positioning or reinforcement.
Installation Requirements for Gaskets
- The sealing surface of the gasket and the flange should be cleaned, and there must be no scratches, spots, or other defects that affect the sealing performance of the connection.
- The outer diameter of the sealing gasket should be smaller than that of the flange sealing surface, and the inner diameter of the sealing gasket should be slightly larger than the inner diameter of the pipe. The difference between the two inner diameters is generally twice the thickness of the sealing gasket to ensure that the sealing gasket will inner edge will not protrude into the container or pipe, so as not to hinder the flow of fluid in the container or pipe.
- The tightening force of the sealing gasket should not exceed the design specification, so as to avoid the excessive compression of the sealing gasket and the loss of rebound ability.
- It is best to use a torque wrench when the gasket is pressed tightly. For large bolts and high-strength bolts, it is best to use hydraulic tensioners. The tightening torque should be obtained through calculation according to the compression of the given sealing gasket, and the oil pressure of the hydraulic tightener should also be determined through calculation.
- When installing the sealing gasket, the nuts should be tightened in sequence. But it should not be screwed once to reach the design value. Generally, it should be cycled at least 2 to 3 times so that the stress distribution of the sealing gasket is even.
- For pressure vessels and pipelines with flammable and explosive media, safety tools should be used when replacing gaskets to avoid sparks caused by tools colliding with flanges or bolts, resulting in fire or explosion accidents.
- If the pipeline leaks, it must be depressurized before replacing or adjusting the installation of the sealing gasket, and it is strictly forbidden to operate under pressure.