CN2212750Y

CN2212750Y - Precisely casted fast heat exchanger for water heater

Info

Publication number: CN2212750Y
Application number: CN 94211000
Authority: CN
Inventors: 程孝龙
Original assignee: Individual
Current assignee: Individual
Priority date: 1994-05-07
Filing date: 1994-05-07
Publication date: 1995-11-15
Anticipated expiration: 2004-05-07

Abstract

The utility model relates to a precise casting type fast heat exchanger for a water heater, which is composed of a plurality of tubes, dozens of fins and an enclosing frame, wherein, the internal diameter of each tube is designed to be smaller in the middle and bigger both ends in order to be convenient for core drawing and demoulding. The middle parts of the fins and the enclosing frame are thicker, and the upper and lower parts of the fins and the enclosing frame become thinner gradually, which is good for heat transfer and demoulding. A matched mold is composed of a movable mold, a still mold, a drawing core, etc. A plurality of semicircular grooves are formed on the opening and closing surfaces of the movable and the still molds. When the molds are closed, cylindrical space can be formed, and a plurality of hollow tubes can be formed by the shaped heat exchanger by inserting the drawing core into the space. The heat exchanger is not welded with any materials but is rapidly cast for molding by one-time moulding by the method of fine casting. The utility model has the advantages of good thermal conductivity, good heat resistance performance, long service life, high productive efficiency, low cost, etc.

Description

Precisely casted fast heat exchanger for water heater

The critical piece of at present commercially available various combustion-type fast water heaters---" heat exchanger " all is the fin-tube heat exchanger with the ashbury metal welding, as common rapid gas water heater, its fin is made through multi-step forming processes such as blanking, punching, flange with the thick copper coin in the 0.5mm left and right sides, in the middle of fin, insert several straight copper tubes then, and with " U " type bend pipe each straight copper tube is contacted, through surface treatments such as cleaning again soldering form (seeing that ISBN7-112-00506-X/TV.368 " coal gas application manual " publishes in May, 89).The operating temperature that this heat exchanger that is welded can bear is very low, in use one overheatedly promptly can damage slightly, and its complicate fabrication process, production efficiency is low, stock utilization is low, production cost is high, and it is also very difficult to take out stains when the pipe inner product has dirt to influence the thermal efficiency.

Purpose one of the present invention provides a kind of that must not weld, pipe, fin, enclose frame etc. by commaterial through a rapid shaping of hot investment casting mold pressing, have good heat-transfer, the life-span is long, production efficiency is high, stock utilization is high, production cost is low, be convenient to remove the heat exchanger that can be applicable to the combustion-type fast water heater of dirt in the pipe.The 2nd, promote the high-new precision casting technology of Application and Development, promote China's industry high speed development.

The visible accompanying drawing of embodiment of the present invention.(accompanying drawing one is the side view of heat exchanger of the present invention)

Heat exchanger of the present invention mainly encloses frame by some fins, several pipe and one and forms, its fin, pipe, enclosing between the frame need not any material welding or bonding, but makes through the hot investment casting one-shot forming with aluminium alloy or copper alloy or other suitable Heat Conduction Materials.Require fin design to become, top and the bottom thicker attenuate gradually according to heat transfer principle and demoulding at the place, plane that each tube axis is determined, enclosing frame also is designed at the place, plane that each tube axis is determined thicker, top and the bottom are attenuate gradually, and make fin and enclose frame and all be basically perpendicular to the determined plane of each tube axis, and selecting this plane is the folding face (being called fractal area A) of mould, like this fin of heat exchanger and enclose frame and not only met to conduct heat and require but also be convenient to the demoulding.The bore design of heat exchanger tube becomes big in the end and small in the middle, is convenient to two ends and uses simultaneously to loose core and make deep and long hole.The pipe of heat exchanger with enclose the frame connecting place and be designed to smooth or also have an annular groove so that Communicating device and parallel sealing ring or " O " RunddichtringO are installed.The average thickness of fin can be made thinlyyer according to technological level as far as possible, about general 0.5-1.5mm for well.The bottom of enclosing frame is designed lowlyer than the bottom of fin, be beneficial to thermal-arrest and and the combustion chamber connect, the Lower Half of enclosing frame contacts with high temperature refrigerant and should design thicklyer, avoids because of the mistake cause thermal damage to reduce thermal resistance.Other parameters such as endotherm area, ips, flow areas etc. can be pressed the heat transfer principle designing and calculating according to the difference of the required watt level of heat exchanger.The mould of making heat exchanger of the present invention is by dynamic model, quiet mould and loose core and push rod etc. is formed, design has several semi-circular recesses on the folding face of dynamic model and quiet mould, then can form the space of column type when dynamic and static mould is closed, the heat exchanger that inserting in this space looses core then can make moulding forms the pipe of several hollows.

Heat exchanger of the present invention is compared with the soldering formula heat exchanger of existing combustion-type fast water heater has following a series of tangible advantage:

1, technological performance: since between fin and the pipe without soldering but be integrated into, so not only good thermal conduction but also the operating temperature height that bears were difficult for cause thermal damage, long service life, product precision height with heat-conducting metal of the same race.

2, economic performance is good: because heat exchanger of the present invention is to be formed by a hot investment casting of mould, (tens seconds just can produce a heat exchanger) highly efficient in productivity, be fit to produce in enormous quantities (can reach 5-10 ten thousand moulds a secondary die life), save material (utilization rate is up to 92%), production technology is simple, so production cost is low.For example the aluminum alloy heat exchanger total production cost in the embodiment of the invention only is with about 1/3 of the existing copper heat exchanger of power.

The shortcoming of heat exchanger of the present invention is because the mould manufacturing expense is bigger, is not suitable for produced in small quantities.

Accompanying drawing is an exemplary embodiments of heat exchanger of the present invention:

1, pipe 2, fin 3, enclose frame 4, linker 5, sealer 6, intake-outlet

Described in detail below in conjunction with the specific embodiment of accompanying drawing heat exchanger of the present invention.

Enclosing the terrace with edge shape of a bottom bigger (130X130), top smaller (123X123) has 4 pipes and 28 transverse fins and 4 longitudinal fins in the frame, enclose the frame bottom than fin bottom more lower slightly (about 20MM), enclose frame at fractal area A place thicker (about 3.5MM), top and the bottom attenuate (about 2MM) gradually, fin is also thicker (about 1.3MM) at fractal area A place, top and the bottom are attenuate (about 0.8MM) gradually, and the ips middle part is less (approximately

9.5), two ends big (

11), the pipe two ends with enclose that the frame junction can be loaded onto sealing ring and Communicating device is together in series four pipes.Can load onto the Inlet and outlet water joint at intake-outlet.Upward measured result is as follows in " a kind of gas kitchen ranges that hot water can be provided continuously " (patent No. 93243507.6) of my invention for this heat exchanger applications: kitchen range power is right fiery 3Kw, the fiery 3.5Kw in a left side, 23 ℃ of inflow temperatures, preheating is promptly exported 43 ℃ hot water after about ten seconds continuously with 4.2 liters/minute flow, power output 5.85Kw, the thermal efficiency is up to 90%.

And its manufacturing cost only be about 1/3 of existing soldering formula copper similar heat exchangers, the height of its technical and economic performance be existing combustion-type fast water heater heat exchanger can not compare.

Because its technical and economic performance of heat exchanger of the present invention is much better than the heat exchanger of existing combustion-type fast water heater, so heat exchanger of the present invention can be widely used for making various combustion-type fast water heaters, to reduce production costs, improves the quality of products.

Claims

1, a kind of by aluminium alloy, copper alloy or other similar Heat Conduction Materials the heat exchanger that is used for the combustion-type fast water heater through hot investment casting mold pressing once-forming, by enclose frame with enclose several pipes that frame is connected, and some fins that are connected with the outer wall of inwall that encloses frame and pipe and with enclose compositions such as seal that frame outer wall and pipe two ends link to each other and Communicating device, it is characterized in that this heat exchanger pipe, fin, enclose the frame three and form through the casting of microcast process one-step mould by identical materials.

2, a kind of heat exchanger according to claim 1 is characterized in that fin is thicker at the root that links to each other with pipe, and last lower limb is attenuate gradually, not only helps heat conduction but also help the demoulding.

3, a kind of heat exchanger according to claim 1 and 2 is characterized in that its middle part diameter of internal diameter of each pipe is less, and the two ends diameter increases gradually, is convenient to the two ends demoulding of loosing core simultaneously.

4, a kind of heat exchanger according to claim 1 and 2, the outer wall that it is characterized in that enclosing frame is a prismoid shaped, little bottom, top is big, the outer wall that links to each other with the pipe two ends is smooth or also is manufactured with annular groove, so that mounting plane sealing ring or " O " V-shaped ring and be convenient to install Communicating device.

5, a kind of heat exchanger according to claim 4, the middle part that it is characterized in that enclosing frame is thicker, and the upper and lower part is attenuate gradually, helps the heat conduction and the demoulding.

6, a kind of heat exchanger according to claim 5 is characterized in that the bottom of enclosing frame is lower than fin, is convenient to thermal-arrest or connects with objects such as combustion chambers.

7, a kind of mould of making the heat exchanger of fast water heater, this mould is by dynamic model, quiet mould and loose core and push rod is formed, it is characterized in that dynamic model and quiet mould are located to meet and meet at the lower bottom part place of housing at the determined plane of the axis of each pipe (fractal area A) respectively when mould is closed.

8, a kind of mould according to claim 7, its two-part each part that is further characterized in that fractal area A place all has several semi-circular recesses, form cylindrical space when mould is closed, loosing core is inserted into the pipe that this space just can make the heat exchanger formation hollow of moulding.