Apparatus and method for scraping the interior of a fluid handling device
AssigneeAisin Seiki Kabushiki Kaisha
InventorsMasahiro Kito, Katsuhiro Mori
Life of this patent
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Abstract
Apparatus and method for scraping the interior of a fluid handling device such as the tubes of a heat exchanger, wherein a scraper in the form of a ribbon, a turbulence promoter, a cylindrical wire mesh or the like is disposed in each tube and scrapingly moved back and forth within the tubes by a spring made of a temperature-responsive shape memory alloy. A fluid handling device provided with the scraping means does not need to be disassembled or even taken off-line. The scraper acts while the fluid handling device is in use, because the temperature-reactive spring can respond to the temperature of fluid flowing through the device or to thermal energy applied at will, as by electric resistance heat.
Claims1
A method of scraping an interior surface of a fluid handling device having a longitudinal axis, a scraping means disposed therein in scraping contact with the interior surface, a fluid outlet manifold, and spring means disposed in the outlet manifold, the spring means being made of a temperature-responsive shape memory alloy and exhibiting a first shape at temperatures below a predetermined temperature and a second shape at temperatures above the predetermined temperature, the spring means operatively engaging the scraping means such that a change of shape of the spring means will cause longitudinal movement of the scraping means, said method comprising the steps of:
- exposing the spring means to the temperature of a fluid in the outlet manifold;
- raising the temperature of the spring means an amount sufficient to cause a change of shape of the spring means from the first shape to the second shape;
- using said change of shape of the spring means to move the scraping means in a first axial direction within the fluid handling device, thereby scraping the interior surface;
- lowering the temperature of the spring means an amount sufficient to cause the spring means to return to the first shape;
- and
- moving the scraping means in a second axial direction within the fluid handling device, thereby further scraping the interior surface.
Dependencies are inferred from the claim text.