Pouring gate capable of exhausting air under negative pressure

Abstract

The utility model relates to a negative pressure air exhaust sprue gate, which belongs to the field of casting facilities and comprises a sprue gate, a filter screen is mounted at the bottom of the sprue gate, a communicating vessel is mounted outside the sprue gate, an air inlet hole is formed in the bottom of the communicating vessel, and a mounting hole is formed in the communicating vessel. The communicating vessel is arranged on the outer side of the funnel-shaped sprue gate, an exhaust pipe connecting hole and a collecting pipe connecting hole are formed in the side face of the communicating vessel, the exhaust pipe connecting hole is connected with the exhaust pipe, and the collecting pipe connecting hole is connected with the collecting pipe. And a J-shaped exhaust pipe and a collecting pipe which are made of ceramics are installed on the periphery of the communicating vessel, a metal solution is injected into the sand mold through the sprue gate, the metal solution burns the polystyrene mold core into gas, and the centrifugal fan exhausts the gas in the sand mold through the collecting pipe, the communicating vessel and the exhaust pipe, so that negative pressure is generated in the sand mold.

Description

Technical Field

[0001] The utility model relates to a gating system with negative pressure air extraction, belonging to the field of casting facilities, and involving facilities for synchronous negative pressure air extraction around the gating system. Background Art

[0002] A gating system is a funnel for pouring molten metal, usually made of ceramic or graphite materials. The gating systems currently used by casting enterprises are divided into two types: slag-filtering and non-slag-filtering. The slag-filtering gating system has a ceramic filter screen at the bottom of the gating system. Its advantage is that it can filter out impurities in the molten metal, but its disadvantage is that the filter screen affects the rapid discharge of the gas generated by the combustion of the polystyrene mold core, resulting in the formation of pores in the castings during pouring. The non-slag-filtering gating system is funnel-shaped with a straight-through interior. Its advantages are fast feeding and fast discharge of the gas generated by the combustion of the polystyrene mold core, but its disadvantages are that it cannot filter out impurities in the molten metal, affects the quality of the castings, and has a high rejection rate. Therefore, there is a need for a gating system that can both filter out impurities in the molten metal and quickly discharge the gas generated by the combustion of the polystyrene mold core, with a low porosity and high yield rate of the castings during pouring.

[0003] Application No.: 2017201665482. A molten iron ceramic filter screen for casting belongs to the field of casting equipment. Using existing high-temperature ceramic materials, the filter screen is processed into a funnel shape. Multiple inwardly protruding partitions are evenly arranged on the inner wall of the filter screen from top to bottom, and grooves are provided between adjacent partitions. Multiple mesh holes are provided on each groove from top to bottom, and the mesh holes penetrate vertically from the inner wall of the filter screen to the outside of the filter screen. The filtering area of the filter screen is increased, the number of mesh holes is increased, and the partitions support the waste slag to prevent blockage of the mesh holes, thus accelerating the filtering speed. A molten iron ceramic filter screen for casting includes a funnel-shaped mesh wall, a fixing ring, partitions, grooves, and mesh holes.

[0004] Application No.: 2021213241088. A ceramic gating system with secondary heating and anti-blocking belongs to the field of casting facilities. It uses a cylindrical feeding pipe, with a conical funnel provided at the top of the feeding pipe, a disc-shaped support plate provided outside the middle of the feeding pipe, a conical filter screen provided upward in the middle of the inside of the feeding pipe, and a spiral induction coil installed outside the upper part of the feeding pipe. The induction coil is connected to a high-frequency electric furnace through a cable.

[0005] The above-mentioned molten iron ceramic filter screen for casting uses high-temperature ceramic materials and processes the filter screen into a funnel shape. The inner wall of the filter screen is arranged with inwardly protruding partitions from top to bottom, grooves are provided between the partitions, and mesh holes are provided on the grooves to achieve the purpose of filtering molten metal. The above-mentioned ceramic gating system with secondary heating and anti-blocking uses a cylindrical feeding pipe, with a filter screen provided in the middle of the inside of the feeding pipe, and an induction coil installed outside the upper part of the feeding pipe to perform secondary heating on the molten metal to make it flow through the filter screen quickly, so as to achieve the purpose of eliminating pores inside the castings. Summary of the Utility Model

[0006] The present utility model provides a gating system with negative pressure air extraction, which includes a funnel-shaped gating system made of ceramics. An annular connector made of ceramics is installed outside the gating system. J-shaped air extraction pipes and collection pipes made of ceramics are installed around the connector. Molten metal is injected into the sand mold through the gating system. The polystyrene core is burned into gas by the molten metal. The centrifugal fan extracts the gas inside the sand mold through the collection pipe, the connector, and the air extraction pipe, creating a negative pressure inside the sand mold.

[0007] The technical solution of the present utility model is as follows: A gating system with negative pressure air extraction includes a gating system 1. A filter screen 2 is installed at the bottom of the gating system 1. A connector 3 is installed outside the gating system 1. An air inlet hole 7 is provided at the bottom of the connector 3. An installation hole 6 is provided inside the connector 3. A suction pipe connection hole 8 and a collection pipe connection hole 9 are provided on the side of the connector 3. The suction pipe connection hole 8 is connected to the suction pipe 5, and the collection pipe connection hole 9 is connected to the collection pipe 4.

[0008] Furthermore, the gating system 1 is a funnel-shaped one made of ceramics. The filter screen 2 installed at the bottom of the gating system 1 is a bowl-shaped one made of ceramics, and the mesh diameter is 5 - 20 mm.

[0009] Furthermore, the connector 3 installed outside the gating system 1 is a hollow annular one made of ceramics. The installation hole 6 provided inside the connector 3 is a tapered hole with a larger upper part and a smaller lower part, and the inner wall of the installation hole 6 is connected to the outer wall of the gating system 1.

[0010] Furthermore, the 4 - 6 circular air inlet holes 7 uniformly provided at the bottom of the connector 3 are circular, and the positions of the air inlet holes 7 are close to the inner edge of the connector 3.

[0011] Furthermore, the 4 - 8 circular suction pipe connection holes 8 uniformly provided on the side of the connector 3 are circular. The suction pipe 5 installed outside each suction pipe connection hole 8 is J-shaped, made of metal, and the elbow at the top of the suction pipe 5 faces downward and is made of ceramics.

[0012] Furthermore, the collection pipe connection hole 9 provided in the front of the connector 3 is circular. The collection pipe 4 installed outside the collection pipe connection hole 9 is J-shaped, made of metal, the elbow at the top faces upward, and the elbow is connected to the centrifugal fan through a steel wire hose.

[0013] Advantages: The gating systems currently used in foundry enterprises are divided into two types: slag filtering and non-slag filtering. The slag filtering gating system has a ceramic filter screen at the bottom of the gating system. The filter screen affects the rapid discharge of the gas generated by the combustion of the polystyrene core, resulting in the casting being prone to porosity. The non-slag filtering gating system is funnel-shaped and has a straight-through type inside. The disadvantage is that it cannot filter impurities in the molten metal, affecting the quality of the casting and resulting in a high scrap rate.

[0014] A gating system with negative pressure air extraction uses a funnel-shaped gating system made of ceramics. An annular connector made of ceramics is installed outside the gating system. J-shaped air extraction pipes and collection pipes made of ceramics are installed around the connector. Molten metal is injected into the sand mold through the gating system. The polystyrene core mold is burned into gas by the molten metal. The centrifugal fan extracts the gas inside the sand mold through the collection pipe, connector, and air extraction pipe to create negative pressure inside the sand mold, achieving the effects of filtering out impurities in the molten metal and quickly discharging the gas generated by the combustion of the polystyrene core mold, resulting in low porosity and high yield of the castings. Description of the Drawings

[0015] Figure 1 It is the front view of a gating system with negative pressure air extraction;

[0016] Figure 2 It is the front view of the gating system and the filter screen;

[0017] Figure 3 It is the structural schematic diagram of the connector, mounting holes, air inlet holes, air extraction pipe connection holes, and collection pipe connection holes;

[0018] In the figure, 1. Gating system; 2. Filter screen; 3. Connector; 4. Collection pipe; 5. Air extraction pipe; 6. Mounting holes; 7. Air inlet holes; 8. Air extraction pipe connection holes; 9. Collection pipe connection holes. Detailed Implementation Modes

[0019] Combined with the drawings and reference numerals, the shape and structure of the present invention are carefully described:

[0020] Embodiment 1

[0021] See the appendix Figures 1-3, A gating system with negative pressure air extraction includes a gating port 1. The gating port 1 is used to introduce molten metal into the sand mold. A filter screen 2 is installed at the bottom of the gating port 1, and the filter screen 2 is used to filter impurities in the molten metal. A connector 3 is installed outside the gating port 1. The connector 3 is used to connect the collection pipe 4, the extraction pipe 5, and the air inlet hole 7. An air inlet hole 7 is provided at the bottom of the connector 3, and the air inlet hole 7 is used to introduce the gas generated by burning the polystyrene core into the connector 3. An installation hole 6 is provided inside the connector 3, and the installation hole 6 is used to fix the gating port 1. A suction pipe connection hole 8 and a collection pipe connection hole 9 are provided on the side of the connector 3. The suction pipe connection hole 8 is used to connect the connector 3 and the suction pipe 5, and the collection pipe connection hole 9 is used to connect the connector 3 and the collection pipe 4. The suction pipe connection hole 8 is connected to the suction pipe 5, and the suction pipe 5 is used to introduce the gas generated by burning the polystyrene core into the connector 3. The collection pipe connection hole 9 is connected to the collection pipe 4, and the collection pipe 4 is used to introduce the gas inside the connector 3 into the centrifugal fan.

[0022] See Appendix Figures 1-2 , The gating port 1 is a funnel-shaped made of ceramic. The filter screen 2 installed at the bottom of the gating port 1 is a bowl-shaped made of ceramic, and the mesh diameter is 5 - 20 mm.

[0023] See Appendix Figures 1-3 , The connector 3 installed outside the gating port 1 is a hollow circular ring made of ceramic. The installation hole 6 provided inside the connector 3 is a tapered hole with a larger upper part and a smaller lower part, and the inner wall of the installation hole 6 is connected to the outer wall of the gating port 1.

[0024] See Appendix Figure 1 and 3 , The 4 - 6 circular air inlet holes 7 evenly provided at the bottom of the connector 3 are circular, and the positions of the air inlet holes 7 are close to the inner edge of the connector 3.

[0025] See Appendix Figure 1 and 3 , The 4 - 8 circular suction pipe connection holes 8 evenly provided on the side of the connector 3 are circular. The suction pipe 5 installed outside each suction pipe connection hole 8 is J-shaped. The suction pipe 5 is made of metal, the elbow at the top is downward, and the elbow is made of ceramic.

[0026] See Appendix Figure 1 and 3 , The collection pipe connection hole 9 provided in the front of the connector 3 is circular. The collection pipe 4 installed outside the collection pipe connection hole 9 is J-shaped. The collection pipe 4 is made of metal, the elbow at the top is upward, and the elbow is connected to the centrifugal fan through a steel wire hose.

[0027] Briefly describe the usage process of the gating system with negative pressure air extraction. Workers load casting sand and polystyrene cores into the sand box, and then fill the casting sand around the polystyrene cores to the same height as above the cores and compact the casting sand. Then, at the central part above the polystyrene core, use a hole opener to dig a circular near-liquid opening in the ceramic insulation layer of the core. The diameter of the near-liquid opening is 6 - 10 cm smaller than the diameter of the communicating vessel 3. Workers use a lifting tool to hoist the assembled gating system 1, communicating vessel 3, collection pipe 4, and exhaust pipe 5 as a whole onto the polystyrene core, so that the filter screen 2 just falls into the excavated near-liquid opening and the communicating vessel 3 completely covers the near-liquid opening. Then, continue to fill the casting sand above the polystyrene core and use a vibrator to compact the casting sand. Workers connect the wire hose above the air inlet of the centrifugal fan to the collection pipe 4 and turn on the centrifugal fan. Workers operate the pouring ladle to slowly pour the molten metal into the gating system 1. The molten metal flows into the polystyrene core through the mesh holes of the filter screen 2. The polystyrene core quickly burns into gas under the roasting of the molten metal. At this time, the interiors of the exhaust pipe 5, communicating vessel 3, and collection pipe 4 are all under negative pressure due to the air extraction effect of the centrifugal fan. The gas generated by the burning of the polystyrene core is quickly sucked into the exhaust pipe 5 and the air inlet hole 7, then enters the interior of the communicating vessel 3, and finally is sucked into the centrifugal fan through the interior of the collection pipe 4. The centrifugal fan pressurizes the gas and sends it into the dust collector. After pouring is completed, turn off the centrifugal fan and wait for the sand box to cool naturally.

Claims

1. A negative pressure exhaust pouring port, comprising a pouring port, characterized in that A filter is installed at the bottom of the pouring port, a communicating vessel is installed outside the pouring port, an air inlet hole is set at the bottom of the communicating vessel, a mounting hole is set inside the communicating vessel, an exhaust pipe connecting hole and a collecting pipe connecting hole are set on the side of the communicating vessel, the exhaust pipe connecting hole is connected to the exhaust pipe, and the collecting pipe connecting hole is connected to the collecting pipe.

2. A negative pressure evacuation pouring port according to claim 1, characterized in that The pouring port is funnel-shaped and made of ceramics, and the filter screen installed at the bottom of the pouring port is bowl-shaped and made of ceramics, with a mesh diameter of 5-20 mm.

3. A negative pressure evacuation pouring port according to claim 1, characterized in that The communicating vessel installed outside the pouring port is a hollow circular ring made of ceramics, the mounting hole arranged inside the communicating vessel is a tapered hole with a larger top and a smaller bottom, and the inner wall of the mounting hole is connected to the outer wall of the pouring port.

4. A negative pressure evacuation pouring port according to claim 1 or 3, characterized in that The 4-6 air inlet holes evenly arranged at the bottom of the communicating vessel are circular, and the positions of the air inlet holes are close to the inner edge of the communicating vessel.

5. A negative pressure evacuation pouring port according to claim 1 or 3, characterized in that The 4-8 exhaust pipe connection holes evenly arranged on the side of the communicating vessel are circular, and the exhaust pipe installed outside each exhaust pipe connection hole is J-shaped. The exhaust pipe is made of metal, and the elbow at the top of the exhaust pipe faces downward and is made of ceramic.

6. A negative pressure evacuation pouring port according to claim 1 or 3, characterized in that The collecting pipe connection hole arranged in front of the communicating vessel is circular, and the collecting pipe installed outside the collecting pipe connection hole is J-shaped. The collecting pipe is made of metal, with the elbow at the top facing upward, and the elbow is connected to the centrifugal fan through a steel wire hose.

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