CN108941462B

CN108941462B - Ceramic filter tube with heating compensation for casting

Info

Publication number: CN108941462B
Application number: CN201810728516.6A
Authority: CN
Inventors: 马广兴
Original assignee: Suzhou Guangxing Mold Co Ltd
Current assignee: Suzhou Guangxing Mold Co Ltd
Priority date: 2018-07-05
Filing date: 2018-07-05
Publication date: 2020-05-19
Anticipated expiration: 2038-07-05
Also published as: CN108941462A

Abstract

This case relates to a take ceramic filter tube for casting of heating compensation, includes: the spiral filter pipe is provided with the heating pipe at the hollow part, two ends of the filter pipe are respectively communicated with the feed inlet and the discharge outlet, the filter pipe comprises a filter screen layer, a ceramic layer and a heat insulation layer from inside to outside, and the inner wall of the ceramic layer is provided with a plurality of sunken slag collecting pits; according to the ceramic filter tube with the heating compensation function for casting, disclosed by the invention, the metal liquid does not need to penetrate through the filter tube, the filtering resistance can be effectively reduced, the gas evolution quantity of a filter screen in filtering can be reduced, and when the metal liquid passes through the filter tube at a high speed, impurities are adsorbed or intercepted by the inner wall of the filter tube, so that a better filtering effect can be achieved.

Description

Ceramic filter tube with heating compensation for casting

Technical Field

The invention belongs to the field of casting, and particularly relates to a ceramic filter tube with heating compensation for casting.

Background

In the foundry industry, inclusions are a very important type of casting defect, accounting for more than half of the total number of defects, which may be present in all castings, but in varying degrees of severity.

In the casting process, impurities contained in the molten metal comprise slag containing calcium carbonate and oxides of iron, manganese and aluminum, unmelted inoculant particles, sulfides, magnesium silicate, residual solvents and other solid impurities, the density of partial impurities is close, the impurities are difficult to float upwards, in addition, in the casting process, other impurities such as sand and the like possibly fall into molten aluminum from a mold gate, if the liquid/solid nonmetallic impurities enter the casting along with the casting, quality problems such as slag holes, sand holes, air holes and the like are easily generated, air leakage can be caused to generate waste products, and the mechanical property of the material can be influenced.

In order to filter impurities to the maximum extent, manufacturing enterprises at home and abroad often place filter screens at the pouring gate, and the common filter screens include iron wire screens, fiber filter screens, ceramic filter screens and straight-hole ceramic filters. The traditional wire netting can directly influence the mechanical property of a casting due to Fe harmful elements, and a cut pouring gate cannot be directly recycled; the fiber filter screen has poor filtering effect, is easy to crack and difficult to install and fix, and easily causes the defects of air holes and slag air holes of the casting; although the ceramic filter screen and the straight-hole ceramic filter aluminum scraps can be recycled, the filter screen has high manufacturing cost and is fragile and difficult to fix.

In addition, the part of the filter screen can cause the casting to generate large air holes due to large gas evolution of the filter screen, so that the rejection rate of the casting is increased and the like.

Disclosure of Invention

The invention aims to provide a casting ceramic filter pipe with heating compensation, which can efficiently filter impurities in molten metal.

It is another object of the present invention to provide a low gas evolution ceramic casting filter tube with heat compensation.

In order to solve the technical problem, the invention discloses a casting ceramic filter tube with heating compensation, which is characterized by comprising: the spiral filter tube is provided with the heating tube at the hollow part, two ends of the filter tube are respectively communicated with the feed inlet and the discharge outlet, the filter tube comprises a filter screen layer, a ceramic layer and a heat preservation layer from inside to outside, and the inner wall of the ceramic layer is provided with a plurality of sunken slag collecting pits. The spiral filter pipe enables high-pressure molten metal to rotate rapidly when passing through, and impurities in the molten metal are thrown to the inner wall of the filter pipe by the generated centrifugal force and collected by a slag collection pit; because of the existence of the filter screen layer, the metal liquid can generate turbulent flow when flowing through the inner wall of the uneven filter pipe, and the impurities are driven to impact the inner wall of the filter pipe, so that the impurities are collected by the slag collecting pit, and the purpose of filtering the impurities is achieved.

Preferably, the pipe diameter of the end of the filter pipe connected with the feed inlet is larger than that of the end of the filter pipe connected with the discharge outlet, and the pipe diameter of the filter pipe is gradually reduced from the end of the feed inlet to the end of the discharge outlet; the inner diameter of one end of the filter pipe connected with the discharge hole is not more than 10 mm. Because the pipe diameter of the filter pipe is gradually reduced from one end of the feed port to one end of the discharge port, the speed of the molten metal in the filter pipe is higher and higher under the wind tunnel effect, so that the centrifugal force applied to impurities in the molten metal is higher and higher, and the impurities are separated; the inner diameter of one end of the filter pipe connected with the discharge hole is not more than 10mm, and if the inner diameter of the filter pipe is too large, the filtering effect is poor.

Preferably, the ceramic layer is a zirconia porous ceramic. The effective area participating in filtration and impurity collection is increased.

Preferably, the slag collection pit is in a bag shape with an opening facing the feed inlet end. So that the impurities do not flow out after entering the slag collecting pit.

Preferably, the depth of the slag collecting pit is 1-3mm, and the maximum diameter is 1-2 mm. The proper pit shape is beneficial to washing out the waste residue after use and putting the waste residue into use again.

Preferably, the mesh diameter of the filter screen layer is 1.4-1.6mm, and the mesh of the filter screen layer is 30-50 meshes. The filter screen plays the effect of preliminary filtration collection.

Preferably, the surface of the filter screen layer is coated with high-temperature resistant paint or refractory material. The net of the filter screen layer can be protected and the net is prevented from polluting molten metal.

Preferably, the heat-insulating layer is made of a ceramic heat-insulating material. Preventing the metal liquid from obviously cooling during the filtration.

Preferably, the heating pipe is a silicon carbide rod heating pipe. The function of compensating heating is achieved.

Preferably, after each use of the ceramic filter tube for casting, the ceramic filter tube needs to be reversely and circularly cleaned and activated for 10-20min by using an acetic acid solution with the concentration of 2-5%, and can be put into use again after being dried; after multiple use, the filter screen layer should be replaced, and during replacement, the filter screen coiled into a spiral shape is rotated to enter the filter pipe to complete installation.

It is worth explaining that the invention has poor filtering effect on impurities with the particle size smaller than 0.1mm in the molten metal, but the influence of the impurities on the quality of castings is small; in addition, in use, a large pressure is applied to the molten metal to make the molten metal flow through the filter pipe at a high speed.

Has the advantages that:

according to the ceramic filter tube with the heating compensation function for casting, disclosed by the invention, the metal liquid does not need to penetrate through the filter tube, the filtering resistance can be effectively reduced, the gas evolution quantity of a filter screen in filtering can be reduced, and when the metal liquid passes through the filter tube at a high speed, impurities are adsorbed or intercepted by the inner wall of the filter tube, so that a better filtering effect can be achieved.

Drawings

FIG. 1 is a schematic structural view of a ceramic filter tube for casting with heating compensation.

Fig. 2 is a schematic cross-sectional view of a filter tube.

Detailed Description

The present invention is further described in detail below with reference to examples so that those skilled in the art can practice the invention with reference to the description.

It will be understood that terms such as "having," "including," and "comprising," when used herein, do not preclude the presence or addition of one or more other elements or groups thereof.

Example 1

As shown in fig. 1 and 2, a ceramic filter tube for casting with heating compensation includes: feed inlet 1, filter tube 2, discharge gate 3 and heating pipe 4, filter tube 2 are the heliciform, and the cavity department of heliciform filter tube 2 is equipped with heating pipe 4, and filter tube 2 both ends are linked together with feed inlet 1 and discharge gate 3 respectively, and filter tube 2 is from inside to outside including filter screen layer 210, ceramic layer 220 and heat preservation 230, the inner wall of ceramic layer 220 is equipped with a plurality of sunken collection slag hole 221.

The pipe diameter of one end of the filter pipe 2 connected with the feed inlet 1 is larger than that of one end of the filter pipe 2 connected with the discharge outlet 3, and the pipe diameter of the filter pipe 2 is gradually reduced from one end of the feed inlet 1 to one end of the discharge outlet 3; the inner diameter of one end of the filter pipe 2 connected with the discharge port 3 is 10 mm.

The ceramic layer 220 is a zirconia porous ceramic.

The slag collection pit 221 is in the shape of a bag with an opening facing the end of the feed inlet 1.

The mesh diameter of the filter screen layer 210 is 1.4-1.6mm, and the mesh of the filter screen layer is 30-40 meshes.

The surface of the filter screen layer 210 is coated with high temperature resistant paint or refractory material.

The depth of the slag collection pit 221 is 1-2.5mm, and the maximum diameter is 2 mm.

The insulating layer 230 is made of ceramic insulating material.

The heating pipe 4 is a silicon carbide rod heating pipe.

Example 2

When the device is used, the heating pipe 4 is electrified and preheated, the feeding hole 1 is connected with a molten metal storage or heat preservation device, the discharging hole 3 is butted with a pouring opening, molten metal enters the filtering pipe 2 under high pressure, flows out of the discharging hole 3 after being filtered, enters a storage box or directly enters the pouring opening to start pouring.

Example 3

After use, 5% acetic acid cleaning solution is introduced into the cooled filter tube, the cleaning solution enters from the discharge port 3 and exits from the feed port 1, the flow velocity of the cleaning solution in the filter tube 2 is kept at 1-2m/s, and hot air is introduced for drying after cleaning and activation for 10-20 min; in practice, the ultrasonic wave with the frequency of more than 50KHz is used for cleaning, so that the cleaning is more thorough.

If large-particle impurities or metal particle residues with larger area occur on the inner wall of the filtering pipe 2 times, the inner wall of the filtering pipe can be washed for 1-2min by hydrochloric acid with the concentration of less than 10%, and then the ratio of the hydrochloric acid to the acetic acid with the concentration of 5% is increased: nitric acid 2: 3 washing the substrate with cleaning solution, back washing for 15-20min, and drying with hot air.

If the filtering effect is poor or partial residue is still present near the filtering pipe opening after cleaning, the filtering net layer 210 should be replaced in time.

While embodiments of the invention have been described above, it is not limited to the applications set forth in the description and the embodiments, which are fully applicable to various fields of endeavor for which the invention may be embodied with additional modifications as would be readily apparent to those skilled in the art, and the invention is therefore not limited to the details given herein and to the embodiments shown and described without departing from the generic concept as defined by the claims and their equivalents.

Claims

1. The utility model provides a take ceramic filter tube for casting of heating compensation which characterized in that includes: the spiral filter tube is provided with the heating tube at the hollow part, two ends of the filter tube are respectively communicated with the feed inlet and the discharge outlet, the filter tube comprises a filter screen layer, a ceramic layer and a heat preservation layer from inside to outside, and the inner wall of the ceramic layer is provided with a plurality of sunken slag collecting pits.

2. A ceramic casting filter tube with heating compensation as claimed in claim 1, wherein the diameter of the end of the filter tube connected with the feed inlet is larger than that of the end of the filter tube connected with the discharge outlet, and the diameter of the filter tube decreases gradually from the end of the feed inlet to the end of the discharge outlet; the inner diameter of one end of the filter pipe connected with the discharge hole is not more than 12 mm.

3. The ceramic cast filter tube with heat compensation of claim 1, wherein the ceramic layer is a zirconia porous ceramic.

4. A ceramic casting filter tube with heat compensation as claimed in claim 1 wherein said collection pit is in the form of a bag open to the feed inlet end.

5. The ceramic casting filter tube with heat compensation of claim 1, wherein the surface of the filter screen is coated with a high temperature resistant coating.

6. A ceramic casting filter tube with heat compensation according to claim 1, wherein the depth of the slag trap is 1-3mm, and the maximum diameter is 1-2 mm.

7. A ceramic casting filter tube with heat compensation as claimed in claim 1 wherein said insulation layer is a ceramic insulation material.

8. The ceramic casting filter tube with heat compensation of claim 1, wherein the heating tube is a silicon carbide rod heating tube.

9. The ceramic casting filter tube with heating compensation of claim 1, wherein the ceramic casting filter tube is cleaned and activated for 10-20min by using an acetic acid solution with a concentration of 2-5% in a reverse circulation manner after each use, and can be put into use again after being dried.