Gas supply gas switching system for zone melting furnace

Abstract

The utility model relates to the technical field of metal purification, in particular to a zone melting furnace gas supply gas switching system which comprises a quartz tube, a gas inlet sealing flange and a gas outlet sealing flange are arranged at the two ends of the quartz tube respectively, a gas inlet pipeline is connected to the gas inlet sealing flange, and the gas inlet end of the gas inlet pipeline is connected with a hydrogen pipeline and an argon pipeline in parallel. A small-flow gas inlet pipeline is connected to a gas inlet pipeline in parallel, independent control of a large-range flow meter and a small-range flow meter is matched, and the requirement for compatibility of high-flow-speed gas inflation after the vacuum building stage and micro-flow hydrogen supply in the smelting stage is met. The problem that high flow speed and micro flow control cannot be both considered in an existing gas supply system is effectively solved.

Description

TECHNICAL FIELD

[0001] The utility model relates to a metal purification technical field, specifically is a regional melting furnace gas supply gas switching system. BACKGROUND

[0002] Rare earth metals are strategic basic materials for the preparation of new energy, semiconductor devices and special alloys, and the purity thereof directly affects the performance stability of high-end equipment. Regional melting method has become the core process for preparing high-purity rare earth metals above 5N level due to its dual advantages of solid-state diffusion and directional crystallization. The process needs to establish a gradient temperature field in a sealed quartz tube and achieve directional migration of impurities through multi-stage gas environment control: a vacuum environment needs to be established in the initial stage to suppress oxidation reaction; trace hydrogen gas needs to be continuously introduced as a reducing gas to maintain the activity of the metal surface during the melting process; and inert gas is required to replace the hydrogen gas to reduce the hydrogen concentration below the explosion limit after the process is completed. The existing gas supply pipeline is distributed in disorder, and it is impossible to balance the high flow rate inflation in the vacuum establishment stage and the micro-flow control in the melting stage. Therefore, a regional melting furnace gas supply gas switching system is proposed. SUMMARY

[0003] The utility model aims at solving above-mentioned problem, to provide a regional melting furnace gas supply gas switching system.

[0004] The utility model solves the problem by adopting the technical scheme of:

[0005] A regional melting furnace gas supply gas switching system, comprising a regional melting furnace quartz tube, the quartz tube is provided with an air inlet sealing flange and an air outlet sealing flange at both ends respectively, an air inlet pipeline is connected to the quartz tube inside on the air inlet sealing flange, a hydrogen pipeline and an argon pipeline are connected in parallel at the air inlet end of the air inlet pipeline, a hydrogen pipeline stop valve is arranged on the hydrogen pipeline, and an argon pipeline stop valve is arranged on the argon pipeline; a gas inflation master stop valve, a vacuum pressure gauge, a large-range flowmeter stop valve and a large-range flowmeter are sequentially arranged on the air inlet pipeline from the air inlet end to the quartz tube direction; a small-flow air inlet pipeline is connected between the vacuum pressure gauge and the large-range flowmeter stop valve on the air inlet pipeline, a small-range flowmeter stop valve and a small-range flowmeter are sequentially arranged on the small-flow air inlet pipeline, and the air outlet end of the small-flow air inlet pipeline is connected to the air inlet pipeline in the downstream direction of the large-range flowmeter;

[0006] An air outlet pipeline is connected to the quartz tube inside on the air outlet sealing flange, a vacuum pumping pipeline and an exhaust pipeline are connected in parallel at the end of the air outlet pipeline, a vacuum pumping stop valve is arranged on the vacuum pumping pipeline, and a vacuum pump is connected to the end of the vacuum pumping pipeline; an exhaust stop valve is arranged on the exhaust pipeline, and the exhaust outlet of the exhaust pipeline leads to the outside.

[0007] Further, the zone melting furnace quartz tube is provided with multiple, the gas inlet pipeline and is located in the downstream direction of the large range flowmeter and is connected with multiple branch gas inlet pipelines in parallel, the multiple branch gas inlet pipelines are connected with the multiple quartz tube gas inlet sealing flanges one by one, the gas inlet pipeline is connected with multiple small flow gas inlet pipelines between the vacuum pressure gauge and the large range flowmeter stop valve, the small flow gas inlet pipelines are sequentially provided with a small range flowmeter stop valve and a small range flowmeter, and the gas outlet ends of the multiple small flow gas inlet pipelines are connected with the multiple branch gas inlet pipelines one by one; the one-to-one corresponding connection structure of the branch gas inlet pipeline and the multiple quartz tubes, in cooperation with the independent shunt design of the small flow gas inlet pipeline, realizes the synchronous independent gas supply of multiple melting furnaces.

[0008] Further, the multiple branch gas inlet pipelines are provided with a one-way valve, the one-way valve is located between the large range flowmeter and the connection point of the small flow gas inlet pipeline and the branch gas inlet pipeline, and the one-way valve allows the gas from the large range flowmeter to pass; the one-way valve on the branch gas inlet pipeline can block the reverse diffusion of hydrogen to the adjacent branch pipeline, so that the gas environment of each quartz tube is independently controllable.

[0009] The utility model discloses the above technical scheme, compared with the prior art, its outstanding features are:

[0010] The utility model discloses the structure of parallel hydrogen pipeline and argon pipeline, realizes the quick switching of hydrogen, argon gas, and the independent control of large range flowmeter and small range flowmeter, meets the compatibility requirement of high flow rate inflation after the vacuum establishment stage and the micro flow hydrogen supply of melting stage, effectively solves the problem that high flow rate and micro flow control cannot be considered in the existing gas supply system.

[0011] The parallel design of the vacuumizing pipeline and the exhaust pipeline can complete the whole process operation of quartz tube vacuumizing, hydrogen reduction atmosphere maintaining and argon replacement in the same system, and is convenient to use. BRIEF DESCRIPTION OF DRAWINGS

[0012] Fig. 1 It is quartz tube gas inlet end system connection structure schematic view for the utility model embodiment;

[0013] Fig. 2 It is quartz tube gas outlet end system connection structure schematic view for the utility model embodiment;

[0014] Marked in the figure: quartz tube 1, gas inlet sealing flange 2, gas outlet sealing flange 3, gas inlet pipeline 4, gas outlet pipeline 5, hydrogen pipeline 6, argon pipeline 7, hydrogen pipeline stop valve 8, argon pipeline stop valve 9, gas filling total stop valve 10, vacuum pressure gauge 11, large range flowmeter stop valve 12, large range flowmeter 13, small range flowmeter stop valve 14, small range flowmeter 15, small flow gas inlet pipeline 16, one-way valve 17, exhaust stop valve 18, exhaust port 19, exhaust pipeline 20, vacuum pipeline 21, vacuum stop valve 22, vacuum pump 23. DETAILED DESCRIPTION

[0015] The utility model will be further explained in connection with the embodiments, the purpose is only in better understanding the utility model content, therefore, the example does not limit the protection scope of the utility model.

[0016] Reference Figs. 1-2 A regional melting furnace gas supply gas switching system, including regional melting furnace quartz tube 1, the quartz tube 1 both ends are provided with gas inlet sealing flange 2 and gas outlet sealing flange 3 respectively, and the gas inlet sealing flange 2 is connected with the gas inlet pipeline 4 that communicates with the inside of quartz tube 1, and the gas inlet pipeline 4 inlet end is connected with hydrogen pipeline 6 and argon pipeline 7 in parallel, the hydrogen pipeline 6 is provided with hydrogen pipeline stop valve 8, and the argon pipeline 8 is provided with argon pipeline stop valve 9;The gas inlet pipeline 4 is sequentially provided with gas filling total stop valve 10, vacuum pressure gauge 11, large range flowmeter stop valve 12 and large range flowmeter 13 from the gas inlet end to the direction of quartz tube 1;The gas inlet pipeline 4 is connected with small flow gas inlet pipeline 16 between vacuum pressure gauge 11 and large range flowmeter stop valve 12, and the small flow gas inlet pipeline 16 is sequentially provided with small range flowmeter stop valve 14 and small range flowmeter 15, and the gas outlet end of small flow gas inlet pipeline 16 is connected with gas inlet pipeline 4 in the downstream direction of large range flowmeter 13;

[0017] The gas outlet sealing flange 3 is connected with the gas outlet pipeline 5 that communicates with the inside of quartz tube 1, and the gas outlet pipeline 5 end is connected with vacuum pipeline 21 and exhaust pipeline 20 in parallel, the vacuum pipeline 21 is provided with vacuum stop valve 22, and the vacuum pipeline 21 terminal is connected with vacuum pump 23;The exhaust pipeline 20 is provided with exhaust stop valve 18, and the exhaust port 19 of exhaust pipeline 20 leads to outdoor.

[0018] The zone melting furnace quartz tube 1 is provided with multiple, the gas inlet pipeline 4 and is located in the downstream direction of the large range flowmeter 13 and is connected with multiple branch gas inlet pipelines which are connected with the gas inlet sealing flanges 2 of the ends of the multiple quartz tubes 1 one by one; the gas inlet pipeline 4 and are connected with multiple small flow gas inlet pipelines 16 between the vacuum pressure gauge 11 and the large range flowmeter stop valve 12, the small range flowmeters 15 and the small range flowmeter stop valves 14 are sequentially arranged on the multiple small flow gas inlet pipelines 16, and the gas outlet ends of the multiple small flow gas inlet pipelines 16 are connected with the multiple branch gas inlet pipelines one by one; the branch gas inlet pipelines are connected with the multiple quartz tubes 1 one by one, and the independent shunt design of the small flow gas inlet pipelines 16 is matched, so that synchronous independent gas supply of multiple melting furnaces is realized.

[0019] The multiple branch gas inlet pipelines are provided with the one-way valves 17, the one-way valves 17 are located between the large range flowmeter 13 and the connection points of the small flow gas inlet pipelines 16 and the branch gas inlet pipelines, and the one-way valves 17 allow the gas to pass in the direction of the large range flowmeter 13; the one-way valves 17 on the branch gas inlet pipelines can block the reverse diffusion of hydrogen to adjacent branch pipelines, so that the gas environment of each quartz tube 1 is independently controllable.

[0020] The working principle of the utility model is as follows: before heating of the zone melting furnace, the vacuum pumping stop valve 22 is opened, the vacuum pump 23 is started, the inside of the quartz tube 1 is pumped to a vacuum state, and then the vacuum pumping stop valve 22 and the vacuum pump 23 are closed; the hydrogen pipeline stop valve 8, the gas filling total stop valve 10 and the large range flowmeter stop valve 12 are sequentially opened, the large range flowmeter 13 is adjusted to 15L / Min, hydrogen passes through the hydrogen pipeline stop valve 8, the gas filling total stop valve 10, the large range flowmeter stop valve 12 and the large range flowmeter 13 in sequence, and then flows through the multiple branch gas inlet pipelines to rapidly flush hydrogen into the quartz tube 1; after completion, the large range flowmeter stop valve 12 is closed.

[0021] When the zone melting furnace is running, small flow hydrogen is introduced, the small range flowmeter stop valve 14 is opened, the small range flowmeter 15 is adjusted to 50ML / Min, hydrogen flows through the small range flowmeter 15 and continuously supplies gas into the quartz tube 1, due to the arrangement of the one-way valves 17, the mutual gas leakage between the multiple quartz tubes 1 is prevented, the phenomenon that the impurity migration path is disordered due to uneven gas supply distribution is avoided, hydrogen enters the quartz tube 1, the exhaust stop valve 18 is opened, and the used hydrogen is discharged from the exhaust port 19, and the small amount of flow hydrogen in the quartz tube 1 is accurately controlled.

[0022] After the zone melting furnace operation is completed, the hydrogen pipeline stop valve 8 and the exhaust stop valve 18 are closed, the vacuum pump 23 is opened, the vacuum stop valve 22 is opened, and the hydrogen is pumped out by the vacuum pump 23. The vacuum pump 23 and the vacuum stop valve 22 are closed, the argon pipeline stop valve 9 is opened, the large range flow meter stop valve 12 is opened, the large range flow meter 13 is adjusted to 15L / Min, argon is rapidly injected into the quartz tube 1, after the pressure gauge 11 is observed to reach positive pressure 0MPA, the argon pipeline stop valve 9 and the large range flow meter stop valve 12 are sequentially closed, the inert gas replacement is completed, and safety is ensured.

[0023] The structure of the parallel hydrogen pipeline and the argon pipeline realizes rapid switching of hydrogen and argon, independent control of the large range flow meter and the small range flow meter is matched, compatibility requirements of high flow rate inflation after the vacuum establishment stage and micro flow hydrogen supply in the melting stage are met, and the problem that high flow rate and micro flow control cannot be considered in the existing gas supply system is effectively solved.

[0024] The parallel design of the vacuum pipeline and the exhaust pipeline can complete the whole process operation of quartz tube vacuumizing, hydrogen reduction atmosphere maintaining and argon replacement in the same system, and use is more convenient.

[0025] The above only describes preferred and feasible embodiments of the utility model, and does not limit the scope of the utility model, and equivalent changes made by applying the utility model specification and its drawings are included in the scope of the utility model.

Claims

1. A gas supply switching system for a zone melting furnace, comprising a quartz tube for the zone melting furnace, characterized in that: The quartz tube is equipped with an inlet sealing flange and an outlet sealing flange at both ends. An inlet pipe is connected to the inlet sealing flange and communicates with the inside of the quartz tube. A hydrogen pipe and an argon pipe are connected in parallel at the inlet end of the inlet pipe. A hydrogen pipe shut-off valve is installed on the hydrogen pipe and an argon pipe shut-off valve is installed on the argon pipe. From the inlet end towards the quartz tube, a main gas filling shut-off valve, a vacuum pressure gauge, a large-range flow meter shut-off valve, and a large-range flow meter are installed in sequence. A small-flow inlet pipe is connected between the vacuum pressure gauge and the large-range flow meter shut-off valve. A small-range flow meter shut-off valve and a small-range flow meter are installed in sequence on the small-flow inlet pipe. The outlet end of the small-flow inlet pipe is located downstream of the large-range flow meter and communicates with the inlet pipe. The vent sealing flange is connected to an vent pipe that communicates with the inside of the quartz tube. The end of the vent pipe is connected to a vacuum pipe and an exhaust pipe. The vacuum pipe is equipped with a vacuum shut-off valve and a vacuum pump is connected to the end of the vacuum pipe. The exhaust pipe is equipped with an exhaust shut-off valve and the exhaust port of the exhaust pipe leads to the outside.

2. The gas supply switching system for a zone smelting furnace according to claim 1, characterized in that: The quartz tubes of the zone melting furnace are provided with multiple inlet pipes. Multiple branch inlet pipes are connected in parallel on the inlet pipe downstream of the large-range flow meter. Each branch inlet pipe is connected to a corresponding quartz tube inlet sealing flange. Multiple small-flow inlet pipes are connected on the inlet pipe between the vacuum pressure gauge and the large-range flow meter shut-off valve. Each small-flow inlet pipe is equipped with a small-range flow meter shut-off valve and a small-range flow meter in sequence. The outlet of each small-flow inlet pipe is connected to a corresponding branch inlet pipe.

3. The gas supply switching system for a zone smelting furnace according to claim 2, characterized in that: One-way valves are installed on multiple branch intake pipes. The one-way valves are located between the connection points of the large-capacity flow meter and the small-capacity intake pipe and branch intake pipes. The one-way valves allow gas from the large-capacity flow meter to pass through.

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