What are the materials used for mechanical seal?
In an engineering sense, the term generally refers to a class of materials that are characterized by their high hardness, high stiffness, low thermal expansion, and good wear resistance. For mechanical seals, these include silicon carbide, silicon nitride, tungsten carbide, and alumina oxide.
How do you select mechanical seal material?
When selecting the seal’s material of construction, be sure to consider the following characterstics of the material:
- Temperature constraints.
- Chemical resistance properties.
- Flexibility.
- Wear resistance.
- Thermal expansion and conductivity properties.
What is the best material for O rings?
What is the Best O-Ring Material For the Application?
- Nitrile (Buna-N) is a general purpose material suited for petroleum oils, water, and some hydraulic fluids.
- Ethylene Propylene Rubber (EPR) operates in a temperature range between -60 degrees Fahrenheit to 250 degrees Fahrenheit.
What type of material is the secondary seal made of?
Typically one of the seal faces is manufactured out of a Carbon Graphite type material and the counter-face out of a harder Ceramic or Carbide material. Seal hardware, springs and drive mechanisms tend to be produced out of metallic materials and the secondary seals are elastomeric or polymeric type materials.
What is mechanical seal and its types?
Mechanical seals are critical components in centrifugal pump systems. These devices preserve the integrity of the pump systems by preventing fluid leaks and keeping contaminants out. Mechanical seal systems are used on various seal designs to detect leakage, control the seal environment and lubricate secondary seals.
How does a mechanical seal work?
A mechanical seal works by having two very flat (generally within 2-3 light bands flat) lapped flat faces. This allows a shaft to turn while maintaining a seal. It is very difficult for leakage to occur (beyond a vapor) if installed properly and in good condition.
What is the difference between black O rings and green O rings?
Difference between black o rings and green o rings Black o rings are primarily neoprene or Nitrile or, in some cases, a mix of the two materials. Green o rings are hydrogenated Nitrile, also known as highly saturated Nitrile, or more commonly known as HNBR.
How many sealing points does a mechanical seal have?
three sealing points
Design. A basic mechanical seal contains three sealing points. The stationary part of the seal is fitted to the pump housing with a static seal –this may be sealed with an o-ring or gasket clamped between the stationary part and the pump housing.
What are the two main parts of a mechanical seal?
A stationary ring (usually the stationary seat) arranged in the stationary part (casing) Secondary seal (usually O-ring) between these parts.
How long should a mechanical seal last?
The typical life expectancy for a mechanical seal of this type balances a variety of factors, including the operating conditions and environment, although three to five years is a reasonable industry estimate.
Are Viton O-rings better?
Crucial Differences While both materials are suitable for moderate temperature applications, Viton® is the superior choice for high temperatures. Viton® standard compounds can withstand temperatures up to 446℉, while Buna o-rings can only handle up to 257℉.
What kind of rubber is used in mechanical seals?
From plant-sourced natural rubber, so named by John Priestly in 1770 for its utility in rubbing away pencil graphite, to petroleum-sourced synthetic rubber first developed around the turn of the 20th century, elastomers and their properties are familiar but should not be overlooked—especially when dealing with mechanical seals.
What should be considered when designing mechanical seals?
The sealed fluid chemistry, temperature range, pressure range, frequency and speed of relative motion, degree of lubrication and abrasives present, and several other interdependent design variables must be considered.
How is elastomer technology used in mechanical seals?
Rubber technology features prominently in radial lip seals, where typical applications have lower pressure-velocity (PV) values relative to those involving mechanical face seals. Still, the flexible elastomer lip must handle considerable relative motion in the form of shaft/bore rotation, reciprocation or a combination of both.
Where can I find a mechanical seal brochure?
Among others, you will find current data sheets in PDF format available for download here. Seal supply systems Brochure 84 Pages (Code: DMS_SSE) The entire product portfolio of systems and components for the cooling, flushing, pressurization and supplying of liquid and gas-lubricated mechanical seals, e.g. quench