A kind of narrow path impeller foundry goods
Technical field
The present invention relates to a kind of narrow path impeller foundry goods.
Background technology
Hot investment casting leaf castings of wheels, due to narrower (the impeller maximum gauge φ more than 200 of the larger runner of such impeller diameter, width of flow path 5-7mm and below 5mm thereof), general this type of impeller of making first goes up two to three layers of sand and then tamped by small space fine sand remaining in runner and seal (being called stifled sand).Be generally directly do like this, as long as slurry is stained with in guarantee and upper sand puts in place, every layer of drying puts in place, and stifled sand puts in place.But whether on shell processed during sand, particularly causing three problems when doing the second third layer shell: 1. because runner is too narrow when going up sand, can't see the slurry of the inside and sand and operating and put in place, if do not have operation to put in place, the later stage pours and is easy to bleed-out water and produces knot iron; Even if 2. the operation of upper sand puts in place, because plane is large, runner is narrow, and runner inside cannot dry (ventilating not smooth); 3. narrow path impeller is all carrying out stifled sand at present, but light blocks up from water inlet and runner exit, and inside is stifled unreal, and such cast also can cause bleed-out water, forms knot iron.Because blade and runner are all curvature of space, these knot iron cannot clear in the later stage, directly caused foundry goods to scrap.
Summary of the invention
In order to solve above-mentioned technical problem, the object of this invention is to provide a kind of narrow path impeller foundry goods, this impeller casting is stained with slurry and upper sand puts in place more, and drying effect is better, and stifled sand is more solid.
In order to realize above-mentioned object, present invention employs following technical scheme:
A kind of narrow path impeller foundry goods, described impeller casting comprises upper cover plate, lower cover and the multiple narrow runner between upper cover plate and lower cover, the width of described narrow runner and highly all successively decreasing gently from inside to outside, the position upper cover plate of described impeller casting being positioned at each narrow runner top center offers the aperture of a band step, and described aperture is square.
Preferably: described aperture is fan-shaped, the impeller casting of all size is more applicable to.
The present invention, owing to have employed above-mentioned technical scheme, by offering aperture on upper cover plate, makes slurry and sand can enter the every nook and cranny of runner from aperture; There is the air of flowing to enter aperture time dry, enable which floor shell before stifled sand fully dry; During later stage sand removal process, from aperture cleaning and the sand that falls, convenient and swift.Structure of the present invention is simple, and effectively can improve Impeller Mass, reduces the scrappage of product, reduces costs.
Accompanying drawing explanation
Fig. 1 is the structural representation after the present invention finishes two or three stratotype shell.
Fig. 2 is the A-A sectional view of Fig. 1.
Fig. 3 is the sectional structure schematic diagram that the present invention finishes the stifled sand after two or three stratotype shell.
Detailed description of the invention
Below in conjunction with accompanying drawing, the specific embodiment of the present invention is made a detailed explanation.
A kind of narrow path impeller foundry goods as shown in Figure 1, Figure 2 and Figure 3, described impeller casting comprises upper cover plate 1, lower cover and the multiple narrow runner 3 between upper cover plate 1 and lower cover, the width of described narrow runner 3 and highly all successively decreasing gently from inside to outside, the position upper cover plate 1 of described impeller casting being positioned at each narrow runner 3 top center offers the aperture 2 of a band step, and described aperture 2 is square.
Weld at aperture 2 upper cover upper cover plate after casting cleaning is complete, although the later stage can produce certain work program, compared with scrap products, or proper way.The benefit being provided with aperture 2 is: when operation starching and upper sand, slurry sand 4 can enter from aperture 2, and therefore some corner operates and put in place, is also convenient to artificially observe operating result, remedies in time; Moving air enters from aperture 2, accelerates drying time and effect, is conducive to the making of later process.Also sand 5 can be poured into plug from aperture 2 when stifled sand real, make upper cover plate 1 powerful support, decrease the bleed-out water of later stage cast.When the later stage clears up, also antiquated sand can be cleared up from this aperture 2, easily and effectively.