A metal salt bath test chamber

Abstract

The utility model belongs to laboratory salt bath test technical field especially relates to a kind of metal salt bath test box, it is characterized in that, including salt fog bin and brine conditioning device, brine conditioning device is connected with the nozzle in salt fog bin by centrifugal pump and pipeline and communicates;The brine conditioning device includes at least three layers of liquid hopper from top to bottom, multiple-position rotary valve and / or peristaltic dosing pump are equipped between adjacent two layers of liquid hopper, the multiple-position rotary valve is connected on the branch line of one-in and multiple-out, branch line is connected with the multiple liquid hopper of adjacent two layers respectively, peristaltic dosing pump is arranged on straight-through pipeline, brine conditioning device lowermost is equipped with liquid collecting tank, centrifugal pump is connected at the outlet of liquid collecting tank.The utility model has the beneficial effects that:the deployment of multiple salt bath components can be quickly completed, especially in the case of salt bath experiments that need to perform multiple salt bath standards, which helps to quickly prepare salt bath liquid;The combination of multiple-position rotary valve and peristaltic dosing pump can improve the degree of automation.

Description

Technical Field

[0001] This utility model belongs to the field of laboratory salt bath testing technology, and in particular relates to a metal salt bath testing chamber. Background Technology

[0002] Metal salt bath testing is mainly used to evaluate the corrosion resistance of metal materials or components in a salt spray environment. It accelerates the testing of corrosion by simulating marine climate or industrial salt spray conditions. The following are the key points: Test principle: A 5% sodium chloride solution is prepared and a salt spray environment is simulated in a salt spray test chamber. Metal samples are exposed to a constant temperature (usually 35°C) and constant humidity environment. Salt solution is continuously sprayed through a spray device, and the degree of surface corrosion is observed to evaluate corrosion resistance. Test Standards: Neutral Salt Spray Test: Uses sodium chloride solution (95% water + 5% sodium chloride), controlled temperature 35℃±2℃, stable spray pressure, continuous for 48-96 hours. Acetic Acid Spray Test: Uses acetate solution (pH 3.5-4.5), suitable for specific materials such as stainless steel. Sample Preparation: Clean surface stains and scratches, ensuring conformity to standard dimensions. Solution Preparation: Uses high-purity sodium chloride and deionized water, strictly controlling concentration and pH value. Environmental Control: The test chamber maintains constant temperature and humidity, and the spray evenly covers the sample surface. Result Evaluation: Corrosion resistance is determined by indicators such as surface corrosion level and weight loss method. Application Areas: Widely used in automotive, electronics, aerospace and other industries, such as body parts and motor components, which require 72-hour salt spray testing to verify corrosion resistance.

[0003] Oxidation salt bath is a common chemical treatment method used in metal surface treatment. It involves dissolving specific salts in a solvent (usually water) to form an oxidizing bath. When metal products are immersed in this bath, the components of the bath react chemically with the metal surface, forming an oxide film. This oxide film has multiple functions, such as improving the metal's corrosion resistance, surface hardness, and wear resistance. The core standards for salt bath testing (usually referring to salt spray testing) include the Neutral Salt Spray Test (NSS), Acetic Acid Salt Spray Test (AASS), Copper Accelerated Acetic Acid Salt Spray Test (CASS), and Alternating Salt Spray Test. These tests are primarily based on international standards such as IEC 60068-2-11, Chinese standard GB / T2423.17-2008, and American standard ASTM B117, and are used to evaluate the corrosion resistance of materials or products.

[0004] The main components of a salt bath are: 1) Oxidizing agents, which are key components in the salt bath formulation. Common oxidizing agents include nitrates and nitrites. Nitrates, such as sodium nitrate (NaNO3), can provide oxygen atoms in the salt bath, causing an oxidation reaction on the metal surface. Nitrites, such as sodium nitrite (NaNO2), have a similar effect and can also stabilize the performance of the salt bath to some extent. Their reaction principle is that at high temperatures or under specific chemical conditions, active oxygen is released, which combines with atoms on the metal surface, promoting the formation of an oxide film. 2) Activators, which accelerate the oxidation reaction. For example, sodium hydroxide (NaOH) can increase the alkalinity of the solution. In an alkaline environment, the oxidation reaction rate on the metal surface tends to be faster. This is because in an alkaline environment, certain substances on the metal surface are more easily dissolved or activated, allowing the oxidizing agent to more effectively contact and react with metal atoms. Moreover, sodium hydroxide can also adjust the pH value of the salt bath, and a suitable pH value is crucial for ensuring the smooth progress of the oxidation reaction. 3) Additives, which are sometimes added to improve the quality and performance of the oxide film. For example, certain organic compounds can improve the density of oxide films. If the oxide film is not dense enough, pores may exist, allowing corrosive media to easily penetrate into the interior of the oxide film, thereby reducing the corrosion resistance of the metal. Additives can also adjust the appearance characteristics of the oxide film, such as its color.

[0005] Therefore, accurately preparing salt bath solutions with qualified component concentrations is the key to quickly completing salt bath experiments. Currently, most methods involve manual measurement and addition of components, which is inefficient. In particular, for salt bath experiments that require multiple salt bath standards, the rapid preparation of multiple components is a major demand in the industry, and there is relatively little relevant published literature. Utility Model Content

[0006] The purpose of this invention is to provide a metal salt bath test chamber that overcomes the shortcomings of the prior art. It is equipped with a salt solution preparation device, which can quickly complete the preparation of various salt bath components. In particular, it is helpful for salt bath experiments that require the execution of multiple salt bath standards, thus improving the efficiency of salt bath testing.

[0007] To achieve the above objectives, this utility model employs the following technical solution: A metal salt bath test chamber includes a salt spray chamber and a salt solution preparation device. The salt solution preparation device is connected to nozzles inside the salt spray chamber via a centrifugal pump and pipelines. The salt solution preparation device includes at least three layers of liquid hoppers from top to bottom, with 1-3 liquid hoppers in each layer. A multi-position rotary valve and / or a peristaltic metering pump is provided between adjacent layers of liquid hoppers. The multi-position rotary valve is connected to a branch with one inlet and multiple outlets, and the branch is connected to multiple liquid hoppers in the upper and lower adjacent layers respectively. The peristaltic metering pump is provided on a straight pipeline, which connects to two liquid hoppers in two adjacent layers. A collection tank is provided at the bottom of the salt solution preparation device, and the outlet of the collection tank is connected to a centrifugal pump.

[0008] Furthermore, the multi-position rotary valve includes a valve body, a valve core, an inlet pipe, an outlet pipe one, an outlet pipe two, and an outlet pipe three. The valve core has two parallel through holes, wherein the center line of the first through hole intersects and is perpendicular to the center line of the valve core, and the center line of the second through hole is parallel to the center line of the first through hole. The inlet pipe and outlet pipe one, outlet pipe two, and outlet pipe three are respectively provided on the valve body, forming a one-inlet-multiple-outlet structure with the first through hole and the second through hole. O-rings are provided at both ends of the first through hole and the second through hole.

[0009] Furthermore, the multi-position rotary valve is an electric valve, with the valve core connected to the output shaft of a servo motor; the valve body and valve core are made of fluoroplastic or reinforced polypropylene.

[0010] Furthermore, the peristaltic metering pump includes a pump casing, a pump impeller, and a hose. The pump impeller is located inside the pump casing. The hose passes between the pump impeller and the pump casing by half a turn and connects to the inlet and outlet of the pump casing. The outer edge of the pump impeller is evenly provided with 3-4 semi-circular protrusions. The hose between the semi-circular protrusions and the pump casing is in a flattened and closed state. The hose between the pump impeller and the pump casing outside the semi-circular protrusions is in a fully inflated state. A stepper motor is connected to the outer shaft of the pump impeller.

[0011] Furthermore, a liquid level sensor is installed in the lowest liquid hopper; a salinity sensor and a pH sensor are installed in the liquid collection tank; an embedded microcomputer is installed in the controller; the embedded microcomputer is connected to a ZigBee transmitter, an LCD display, a power supply, an RS-485 interface, and a USB interface; the liquid level sensor, salinity sensor, and pH sensor are connected to the embedded microcomputer through the RS-485 interface; and the embedded microcomputer communicates with the central control room through the ZigBee protocol.

[0012] Furthermore, the salt spray chamber is a top-opening box with a transparent cover. A crossbar is installed inside the chamber, and a hook is installed on the crossbar. The bottom of the salt spray chamber is connected to the collection tank via a return pipe.

[0013] Furthermore, a filter screen is provided at the inlet of the return pipe.

[0014] Compared with the prior art, the beneficial effects of this utility model are: Equipped with a salt solution preparation device, it can quickly prepare various salt bath components. Especially in situations where multiple salt bath standards need to be performed, it helps to quickly prepare the salt bath solution and improve the efficiency of salt bath testing. The combined application of multi-position rotary valves and peristaltic metering pumps can improve the automation of dispensing operations, while ensuring the stability of dispensing accuracy and reducing the problem of excessive component errors caused by human negligence. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of an embodiment of the present utility model; Figure 2 This is a schematic diagram of the valve position of the multi-position rotary valve in an embodiment of this utility model; Figure 3 This is a schematic diagram of the peristaltic metering pump structure in an embodiment of the present invention; Figure 4 for Figure 3 External view; Figure 5 This is a schematic diagram of the controller circuit in an embodiment of the present invention; In the diagram: 1-Salt spray chamber, 2-Salt solution preparation device, 3-Centrifugal pump, 4-Nozzle, 5-Liquid hopper, 6-Multi-position rotary valve, 7-Peristaltic metering pump, 8-Collection tank, 9-Valve housing, 10-Valve core, 11-Inlet pipe, 12-Outlet pipe one, 13-Outlet pipe two, 14-Outlet pipe three, 15-First through hole, 16-Second through hole, 17-O-ring, 18-Pump housing, 19-Pump wheel, 20-Hose, 21-Inlet, 22-Outlet, 23-Level sensor, 24-Salinity sensor, 25-pH sensor, 26-Cover, 27-Crossbar, 28-Hook, 29-Filter screen, 30-Return pipe, 31-Stepper motor, 32-Semi-circular protrusion. Detailed Implementation

[0016] The technical solution of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of this utility model, but not all embodiments.

[0017] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. The components of the embodiments of this utility model described and shown in the accompanying drawings can typically be arranged and designed in many different configurations. Therefore, the following detailed description of the embodiments of this utility model provided in the accompanying drawings is not intended to limit the scope of the claimed utility model, but merely represents selected embodiments of the utility model.

[0018] See Figure 1 This is a schematic diagram of an embodiment of a metal salt bath test chamber according to the present invention. It includes a salt mist chamber 1 and a salt solution preparation device 2. The salt solution preparation device 2 is connected to the nozzles 4 inside the salt mist chamber 1 through a centrifugal pump 3 and pipelines. The salt solution preparation device 2 includes at least three layers of liquid hoppers 5 from top to bottom. The top layer has one liquid hopper, and the second and bottom layers each have three liquid hoppers. A multi-position rotary valve 6 and / or a peristaltic metering pump 7 are provided between two adjacent layers of liquid hoppers 5. The multi-position rotary valve 6 is connected to a branch with one inlet and multiple outlets. The branch is connected to multiple liquid hoppers 5 in the upper and lower adjacent layers respectively. The peristaltic metering pump 7 is provided on a straight pipeline. The straight pipeline connects two liquid hoppers 5 in two adjacent layers. A collection tank 8 is provided at the bottom of the salt solution preparation device 2. The outlet of the collection tank 8 is connected to the centrifugal pump 3. A liquid level sensor 23 is provided in the bottom layer of liquid hopper 5. A salinity sensor 24 and a pH sensor 25 are provided in the collection tank 8. The salt spray chamber 1 is a top-opening box with a transparent cover 26. A crossbar 27 is installed inside the chamber, and hooks 28 are attached to the crossbar 27. The bottom of the salt spray chamber 1 is connected to the collection tank 8 via a return pipe 30. The salt solution in the salt spray chamber 1 flows back to the collection tank 8 by gravity. To reduce the backflow of impurities, a polypropylene filter screen 29 is installed at the inlet of the return pipe 30.

[0019] See Figure 2 The multi-position rotary valve 6 includes a valve body 9, a valve core 10, an inlet pipe 11, an outlet pipe 12, an outlet pipe 13, and an outlet pipe 14. The valve core 10 has two parallel through holes. The center line of the first through hole 15 intersects and is perpendicular to the center line of the valve core 10. The center line of the second through hole 16 is parallel to the center line of the first through hole 15. The inlet pipe 11 and the outlet pipes 12, 13, and 14 are respectively provided on the valve body 9, forming a one-inlet-multiple-outlet structure with the first through hole 15 and the second through hole 16. O-rings 17 are provided at both ends of the first through hole 15 and the second through hole 16.

[0020] The multi-position rotary valve 6 is an electric valve. The valve core 10 is connected to the output shaft of a servo motor (not shown in the figure). Under the control of the controller, the servo motor rotates to angles of -45°, -30°, 0°, +30°, and +45°, which correspond to the four positions of the multi-position rotary valve 6. Among them, -45°(a) and +45°(e) are both closed positions. This structure can achieve rapid shut-off at the nearest point. The valve body 9 and the valve core 10 are made of fluoroplastic or reinforced polypropylene, which has the function of preventing salt corrosion.

[0021] See Figure 3-4 The peristaltic metering pump 7 includes a pump housing 18, a pump impeller 19, and a hose 20. The pump impeller 19 is located inside the pump housing 18. The hose 20 passes between the pump impeller 19 and the pump housing 18, making a half-turn loop, and connects to the inlet 21 and outlet 22 of the pump housing 18. The outer edge of the pump impeller 19 is evenly provided with three semi-circular protrusions 32. The hose 20 between the semi-circular protrusions 32 and the pump housing 18 is in a flattened and closed state, while the hose 20 between the pump impeller 19 and the pump housing 18 outside the semi-circular protrusions is in a fully inflated state. To reduce hose wear, the semi-circular protrusions 32 can also be roller structures. A stepper motor 31 is connected to the outer shaft of the pump impeller 19. When the pump impeller 19 rotates once, it carries out liquid from a section of the hose. Under constant liquid pressure, the flow rate of the pump impeller 19 in one rotation is stable and accurate, enabling precise dispensing.

[0022] See Figure 5 The controller is equipped with an embedded microcomputer, which is connected to a ZigBee transmitter, an LCD display, a power supply, an RS-485 interface, and a USB interface. The liquid level sensor, salinity sensor, and pH sensor are connected to the embedded microcomputer via the RS-485 interface. The embedded microcomputer communicates with the central control room via the ZigBee protocol. The central control room can remotely receive data on the salt level, salinity, and pH value of the metal salt bath test chamber, and remotely control the centrifugal pump 3, the multi-position rotary valve 6, and the peristaltic metering pump 7. At the same time, it monitors the salt bath test process to ensure that it meets the requirements of the national standard for salt spray testing and guarantees the standardization and repeatability of the test results.

[0023] In this embodiment of the invention, the various components of the salt solution and the cleaning solution are separately loaded into the liquid hopper 5. A multi-position rotary valve 6 is used to divert and mix the salt solution from top to bottom. A peristaltic metering pump 7 ensures precise preparation. The prepared salt solution is then placed in the bottom liquid hopper for later use. The sample to be subjected to salt bath is hung on the hook 28 in the salt spray chamber 1, and the chamber lid 26 is closed. The required amount is added to the collection tank 8. The controller starts the centrifugal pump 3, and the nozzle 4 sprays the salt solution to form a salt mist, thus beginning the testing process. After the test, the sample is allowed to stand for 1 hour. Then, the chamber lid 26 is opened, the sample is removed, rinsed with clean water, and dried. The salt spray resistance performance of the sample can then be evaluated according to relevant testing standards.

[0024] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A metal salt bath test chamber, characterized in that, The device includes a salt spray chamber and a salt solution preparation device. The salt solution preparation device is connected to the nozzles inside the salt spray chamber via a centrifugal pump and pipeline. The salt solution preparation device includes at least three layers of liquid hoppers from top to bottom, with 1-3 liquid hoppers in each layer. A multi-position rotary valve and / or a peristaltic metering pump are provided between two adjacent layers of liquid hoppers. The multi-position rotary valve is connected to a branch with one inlet and multiple outlets. The branch is connected to multiple liquid hoppers in two adjacent layers. The peristaltic metering pump is provided on a straight pipeline. The straight pipeline connects two liquid hoppers in two adjacent layers. A collection tank is provided at the bottom of the salt solution preparation device. The outlet of the collection tank is connected to a centrifugal pump.

2. The metal salt bath test chamber according to claim 1, characterized in that, The multi-position rotary valve includes a valve body, a valve core, an inlet pipe, an outlet pipe one, an outlet pipe two, and an outlet pipe three. The valve core has two parallel through holes, wherein the center line of the first through hole intersects and is perpendicular to the center line of the valve core, and the center line of the second through hole is parallel to the center line of the first through hole. The inlet pipe and outlet pipe one, outlet pipe two, and outlet pipe three are respectively provided on the valve body, forming a one-inlet-multiple-outlet structure with the first through hole and the second through hole. O-rings are provided at both ends of the first through hole and the second through hole.

3. A metal salt bath testing chamber according to claim 2, characterized in that, The multi-position rotary valve is an electric valve, with the valve core connected to the output shaft of a servo motor; the valve body and valve core are made of fluoroplastic or reinforced polypropylene.

4. A metal salt bath test chamber according to claim 1, characterized in that, The peristaltic metering pump includes a pump casing, a pump impeller, and a hose. The pump impeller is located inside the pump casing. The hose passes between the pump impeller and the pump casing by half a turn and connects to the inlet and outlet of the pump casing. The outer edge of the pump impeller is evenly provided with 3-4 semi-circular protrusions. The hose between the semi-circular protrusions and the pump casing is in a flattened and closed state. The hose between the pump impeller and the pump casing outside the semi-circular protrusions is in a full state. A stepper motor is connected to the outer shaft of the pump impeller.

5. A metal salt bath testing chamber according to claim 1, characterized in that, The lowest layer of the liquid hopper is equipped with a liquid level sensor; the liquid collection tank is equipped with a salinity sensor and a pH sensor; the controller is equipped with an embedded microcomputer, which is connected to a ZigBee transmitter, an LCD display, a power supply, an RS-485 interface, and a USB interface. The liquid level sensor, salinity sensor, and pH sensor are connected to the embedded microcomputer via the RS-485 interface, and the embedded microcomputer communicates with the central control room via the ZigBee protocol.

6. A metal salt bath test chamber according to claim 1, characterized in that, The salt spray chamber is a top-opening box with a transparent lid. A horizontal bar is installed inside the chamber, and a hook is attached to the horizontal bar. The bottom of the salt spray chamber is connected to the collection tank via a return pipe.

7. A metal salt bath test chamber according to claim 6, characterized in that, A filter screen is installed at the inlet of the return pipe.

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