Introducing
Your new presentation assistant.
Refine, enhance, and tailor your content, source relevant images, and edit visuals quicker than ever before.
Trending searches
heat transfer
32
Heat Transfer Accessories (steam dryer& trap)
Thank You!
Nada Samy Attya 6161392
Yasmein Mohamed Elshamy 6161393
Ahmed Gamal Elsaeed 6161394
Ibrahem Essam Eldein 6161395
Azeiza Eed Elshahab 6161396
Hajar Ibrahim zaky 6161386
Tasneim Zedan Shehab 6161387
Sara Fared Marouf 6161389
Rehab Magdy Saad 6161390
Salma Hamdy 6161391
Steam Dryers (water separators)
In all engines, wet steam reduces the thermal efficiency .
Water is separated from steam by means of an apparatus called "water separator" or "steam dryer".
The principle of such an apparatus depends upon the fact that steam has an average speed of about mile minute and, being a vapor, it may be rapidly changed its direction, whereas water carried in the steam tends to continue in the original paths
Hence, separators, in general act by causing a quick-change of direction of wet steam, so that the water is left behind whilst the dry steam goes forward.
Steam Dryers
FORM 1
-One form of steam dryers a consists of a vessel with a vertical plate reaching almost to the bottom. The wet steam enters the vessel at the top, passes down one side and up the other side, leaving the water in the bottom of the vessel.
Form 1
photo 1
Subtopic 2
video 1
FORM 2
Form 2
•In another form of water separators, (b)the wet steam is passed into the upper part of a cylindrical vessel encircling a central pipe, the outside wall of the central pipe resembles a screw, so that the current of wet steam which enters the space between the pipe and the outer vessel must pass a downward spiral course round the pipe.
•The centrifugal-force generated by this spiral course throws the water an the Inner wall of the outer vessel, The water drips down Into the bottom of the vessel while the dry steam, which can rapidly change its direction, passes up and out by the pipe.
A steam dryer is always fitted near the boiler to separate water carried forward mechanically from the boiler, and others may also be fitted at the end of long stretches of steam pipes.
Photo
video
Steam Traps
- To ensure maximum heating efficiency the apparatus should minimize the amount of condensate, (as well as air and other incondensable gases),present in the jacket.
- If the condensate is allowed to build up it will gradually reduce the area over which steam can condense, and therefore progressively slow down the heating process. If the condensate completely fills the jacket then heating will stop.
Steam traps
- Water always contains dissolved air, air is a permanent gas which remains when the steam condenses to form a condense film and hence forms an air layer in contact with condensate. As air is a very poor conductor it forms a formidable barrier to heat flow.
- Non-Condensable gases: Gases other than air such as carbon dioxide exist inside steam systems.
- Condensate and air can be removed and steam retained by using a suitably designed device known as a steam trap.
- Steam trap is an automatic valve quite literally ‘purges’ condensate, (as well as air and other incondensable gases), out of the system, allowing steam to reach its destination in a dry a state as possible to perform its task efficiently and economically
Title
Types :-
Types
- Thermostatic types : detect the variations in the temperature between steam and condensate at the same pressure (Liquid expansion steam trap) .
- Mechanical types : operate by using the difference in the density between steam and condensate (Inverted bucket steam trap).
Thermostatic Steam Traps (liquid expansion steam trap)
Thermostatic steam traps
Principle
Condensate can lose sensible heat and thus be at a temperature which is lower than the steam. A common form of thermostatic steam trap is the Liquid expansion steam trap shown diagrammatically
Title
This trap contains a closed metal cartridge A. to one end of this metal cartridge is connected a collapsible corrugated tube B.The left hand end of the tube B is sealed, and to its attached the stem of the valve C.
The space between the cartridge and the corrugated tube is filled with oil. The collection of condensate against the valve, losing heats by radiation, cools the cartridge; the oil contracts, the valve opens, and the condensate are blown out. When the condensate is all discharged and steam enters the trap again, the cartridge expands and the trap closes.
Thermostatic steam traps (Liquid expansion steam trap)
Photos
Video
Mechanical steam traps (Inverted bucket steam trap)
Principle
- Condensate is more dense than steam .
Mechanical steam traps
Title
- As can be seen, In (i) the bucket hangs down, pulling the valve off its seat. Condensate flows under the bottom of the bucket filling the body and flowing away through the outlet
- In (ii) the arrival of steam causes the bucket to become buoyant, it then rises and shuts the outlet.
- In (iii) the trap remains shut until the steam in the bucket has condensed or bubbled through the vent hole to the top of the trap body. It will then sink, pulling the main valve off its seat. Accumulated condensate is released and the cycle is repeated.