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sid_galt
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What material are oilless seals made of?
Do they generate more friction than oiled seals?
Do they generate more friction than oiled seals?
To get a bit more specific, what area of the compressor? I think the type used is going to depend if you're talking about sealing around a shaft or a vane tip, etc...sid_galt said:Yes, I'm talking about rotating seals, e.g. a vane compressor.
An engine which works on the vane compressor principle to be exact for my Intel competition. Sealing is of course again a problem as well as the excess oil consumed.Q_Goest said:Hey Sid, you ask a lot of questions about vane compressors. What's up with that? Are you working on a design or something?
Vane tip.FredGarvin said:To get a bit more specific, what area of the compressor? I think the type used is going to depend if you're talking about sealing around a shaft or a vane tip, etc...
FredGarvin said:You can also have carbon seals which use a carbon element with a very hard runner. The seal is the mating face between the two. The runner is attached to the shaft and the carbon is static.
Rotary vane compressors use either carbon vanes for low pressure oil-free duties, or asbestos/steel vanes for lubricated duties. Various asbestos (and similar performance asbestos free) compounds are widely used for low pressure applications, up to about 3 barg. Over and above this pressure, the vanes are steel or cast iron because of the substantial bending forces present when the machine is running.
In a carbon seal arrangment, there are two components; the carbon seal itself and the runner. The carbon seal is usually the stationary object. The runner is attached to something that is moving, like a rotating shaft. The runner (moving) presses against the carbon element and the mating faces is where the seal takes place. Just like anything, they have their advantages and disadvantages.sid_galt said:What is a runner?
Q_Goest said:I'd suggest you forget about comparing this to a compressor, compare it to a 2 stroke IC engine instead. Run it with oil in the gas and make the vanes the same material as piston rings. They can be simple iron or steel on cast iron cylinder. I've seen high performance rings that are hard chrome plated, but you probably don't want to go to that expense. I'd suggest looking to see what materials piston rings are made from and use that. Also what material the cylinder liner is made from and use that.
Maybe making three segments with two segments on the sides with one end on the top shaped like an elbow?Q_Goest said:How are you going to seal the edges of the vane? Just a close fit might work, but that might be improved upon by making the vane segmented somehow.
Q_Goest said:Also, the end of the rotating cylinder needs to be a very close fit. How could that be sealed better? Don't know - thoughts?
FredGarvin said:In a carbon seal arrangment, there are two components; the carbon seal itself and the runner. The carbon seal is usually the stationary object. The runner is attached to something that is moving, like a rotating shaft. The runner (moving) presses against the carbon element and the mating faces is where the seal takes place. Just like anything, they have their advantages and disadvantages.
I'm not quite following you on that one. The seal ends up being a surface. Take two cylinder ends of the same size and butt them up together. The seal would be the interface between the two ends with one cylinder rotating and the other stationary. I'll see if I can find a picture.sid_galt said:Does that mean that the seal has essentially a line contact with the housing?
What is the intent of the presentation? Is this website the "Intel Science Talent Search" you're entering?Any suggestions on the presentation?
Oilless seals are used to prevent leakage of fluids or gases in mechanical systems, while eliminating the need for lubrication with oil. This helps to reduce maintenance costs and improve the efficiency of the system.
The most common materials used for oilless seals are polytetrafluoroethylene (PTFE), commonly known as Teflon, and other fluoropolymers such as PFA and FEP. Other materials include graphite, carbon, and ceramic.
No, oilless seals are not suitable for all types of fluids. They are typically used for non-corrosive fluids such as water, air, and gases. Some specialized oilless seals may be suitable for use with certain chemicals, but it is important to consult the manufacturer's specifications for compatibility.
Oilless seals have a self-lubricating property, meaning they have a low coefficient of friction and can operate without the need for added lubrication. This is achieved through the use of materials that have a low friction coefficient and can withstand high temperatures and pressures.
Some advantages of using oilless seals include lower maintenance costs, improved efficiency, and reduced risk of contamination. They also have a longer lifespan compared to traditional oil-lubricated seals due to their self-lubricating properties. Additionally, they are more environmentally friendly as they do not require the use of oil.