Hi mauro3763061,
Thank you for an interesting question.
Peristaltic pump
http://www.fact-index.com/p/pe/peristaltic_pump.html
"A peristaltic pump is a type of positive displacement pump used for
pumping a variety of specialized fluids. The fluid is contained in a
flexible hose fitted inside a circular pump casing. A rotor with a
number of cams (also called 'shoes' or 'wipers') attached to the
external circumference compresses the flexible tube. As the rotor
turns, the part of tube under compression rotates thus forcing the
fluid to be pumped to move through the tube. This process is called
*peristalsis* and is used in many biological systems such as the
gastrointestinal tract. The pump casing is typically filled with
lubricant to prevent abrasion of the exterior of the pump tube.
Since the only part of the pump in contact with the fluid being pumped
is the interior of the tube, it is easy to sterilise and clean the
inside surfaces of the pump. Furthermore, since there are no moving
parts in contact with the fluid, peristaltic pumps are inexpensive to
manufacture."
Typical applications
Dialysis machines
Food manufacturing
Pharmaceutical production
Sewage sludge
tabletop decorative fountains and waterwalls
*****
*Peristalsis*
http://www.fact-index.com/p/pe/peristalsis.html
"Peristalsis is the process of involuntary wave-like successive
muscular contractions by which food is moved through the digestive
tract.
The large, hollow organs of the digestive system contain muscle that
enables their walls to move. The movement of organ walls can propel
food and liquid and also can mix the contents within each organ.
Typical movement of the esophagus, stomach, and intestine is called
peristalsis. The action of peristalsis looks like an ocean wave moving
through the muscle. The muscle of the organ produces a narrowing and
then propels the narrowed portion slowly down the length of the organ.
These waves of narrowing push the food and fluid in front of them
through each hollow organ."
The process of peristalsis is used by peristaltic pumps.
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All About Pumps - Peristaltic Pump (see animated image)
http://www.animatedsoftware.com/pumpglos/peristal.htm
"One of the main advantages of the Peristaltic Pump is cleanliness. It
also utilizes another advantage: Fragile blood cells are not damaged
by this pump.
The flexible tube (in this drawing its edges are blue and yellow for
clarity) is connected on the inlet side to the patient's artery, and
on the outlet side to the patient's vein.
In this example three rollers on rotating arms pinch the tube against
an arc and move the fluid along. There are usually three or four sets
of rollers.
Peristaltic pumps have a variety of medical applications. They can be
used to add nutrients to blood, to force blood through filters to
clean it, or to move blood through the body and lungs during open
heart surgery."
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PERISTALTIC PUMPS: THE HOT NEW TECHNOLOGY
http://www.watson-marlow.com/
The perfect pump
"Peristaltic pumps have no valves, seals or glands, and the fluid
contacts only the bore of the hose or tube. Simple to install, easy to
use, and quick to maintain, they are the hot new technology, and the
world's fastest-growing pump type."
They are the perfect pump
http://www.watson-marlow.com/watson-marlow/perfect.htm
"Nothing but the hose or tube touches the fluid, eliminating the risk
of the pump contaminating the fluid, or the fluid contaminating the
pump.
The animation shows fluid being drawn into a pump, trapped between two
shoes (in a Bredel pump) or rollers (in a Watson-Marlow pump), and
finally being expelled from the pump. The gaps between the packets of
fluid are shown only to help visualise the action.
The complete closure of the hose which is squeezed between a shoe and
the track gives the pump its positive displacement action, preventing
backflow and eliminating the need for check-valves when the pump is
not running."
- There is no contamination of the pump or fluid
- Ideal for slurries, viscous, shear-sensitive and aggressive fluids
- Easy to install, simple to operate, inexpensive to maintain
- Pump design prevents backflow and syphoning without valves
- Wide range of tubing includes industrial, food-grade and medical
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http://www.innovativeaquatics.com/Pages/faq.html
What is a "Peristaltic Pump"? How does it work?
"Peristaltic pumps use a flexible tubing that is compressed by
rollers, and the more often the motor turns, the more liquid is moved
and the more flow you get per hour. In our pumps, tension of the
mechanism stretches the tubing over the rollers, so that as the roller
assembly turns, the liquid is pumped - it's very similar to getting
toothpaste out of the tube."
Do I have to put the liquid above the pump?
"Absolutely not! The pump will draw the liquid up from a container up
to 3 feet below the pump, and will pump up at least 10 feet absolute
minimum."
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Best regards,
tlspiegel |
