CN118789461A - A method for surface treatment of railway freight car - Google Patents

Abstract

The present application relates to a method for surface treatment of a railway freight car, the method for surface treatment of a railway freight car comprising the following steps: testing the humidity and temperature of the environment in which the railway freight car is located, and when the humidity and temperature of the environment in which the railway freight car is located reach predetermined conditions, preheating the railway freight car; performing dry ice sandblasting on the railway freight car; and baking the railway freight car. The present application implements dry ice sandblasting on the railway freight car, which is dust-free, low in noise, has no problems of embedding in the substrate and recycling, is not easy to deform thin workpieces, and has the advantages of not easily causing damage to the cleaned surface, low cost, and rapid cleaning.

Description

A method for surface treatment of railway freight car

Technical Field

The present invention relates to railway technology, and in particular to railway freight cars.

Background Art

At present, for railway freight cars, such as C70 open wagons, BH1 insulated wagons, X70 flat wagons, etc., overall sandblasting pretreatment or manual grinding is used after vehicle assembly to improve the cleanliness and roughness of the vehicle surface, remove surface oil, oxides, rust, and form a rough surface to promote the close anchoring of the substrate and the paint film. Sandblasting pretreatment is simple to operate and has wide applicability. Therefore, it has been widely used in the industry for a long time, but it also has some shortcomings: (1) Dust and noise pollution, special protective measures must be used; (2) For plastic substrates such as aluminum alloys, sand particles are easily embedded in the substrate, which is not suitable for sandblasting; (3) Sandblasting of thin workpieces is likely to cause deformation of the workpiece; (4) The recovery and treatment of residual sand particles on the workpiece increases the processing cost.

Summary of the invention

The embodiment of the present application provides a method for surface treatment of railway freight cars to solve the technical problems of dust and noise pollution, easy embedding into plastic substrates, easy deformation of thin workpieces, and increased processing costs for sand recovery and processing in existing sandblasting processes.

The present application provides a method for surface treatment of a railway freight car, the method for surface treatment of a railway freight car comprising the following steps:

Testing the humidity and temperature of the environment in which the railway freight car is located, and when the humidity and temperature of the environment in which the railway freight car is located reach predetermined conditions, preheating the railway freight car;

performing dry ice blasting on the railway freight car;

The railway freight car is subjected to a baking treatment.

In some embodiments of the present application, the predetermined condition is humidity>80% or temperature<12°C.

In some embodiments of the present application, the preheating temperature is 30-40°C.

In some embodiments of the present application, the preheating time is 15 to 30 minutes.

In some embodiments of the present application, the dry ice blasting is performed by a dry ice cleaning machine. During the dry ice blasting process, the working pressure of the dry ice cleaning machine is 0.2-0.4 MPa.

In some embodiments of the present application, the dry ice cleaning machine includes a spray gun for spraying dry ice, the length of the spray gun is 30 to 50 cm, the nozzle diameter of the spray gun is 1 to 2 cm, and the length is 5 to 8 cm.

In some embodiments of the present application, the distance between the nozzle and the surface of the railway freight car is 5 to 20 cm.

In some embodiments of the present application, the baking temperature is not less than 40° C., and the baking time is not less than 30 min.

In some embodiments of the present application, the railway freight car is one of an open car, a box car, a flat car, a tank car, and an insulated car.

In some embodiments of the present application, the material of the truck surface is one of aluminum alloy, stainless steel and carbon steel.

The above technical solution provided by the embodiment of the present application has the following advantages compared with the prior art:

The method for surface treatment of railway freight cars provided in the embodiment of the present application implements dry ice sandblasting technology on the railway freight cars. It is dust-free, low-noise, and has no problems of embedding in the substrate and recycling. It is also not easy to deform thin workpieces. It also has the advantages of not easily causing damage to the cleaned surface, low cost, and rapid cleaning.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

FIG1 is a schematic flow chart of a method for surface treatment of a railway freight car provided in an embodiment of the present application.

DETAILED DESCRIPTION

In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

Unless otherwise specified, the terms used herein should be understood as commonly used in the art. Therefore, unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art to which this application belongs. In the event of a conflict, this specification takes precedence.

Unless otherwise specified, various raw materials, reagents, instruments and equipment used in this application can be purchased from the market or prepared by existing methods.

The existing sandblasting process has technical problems such as dust and noise pollution, easy embedding into plastic substrate, easy deformation of thin workpieces, and increased processing costs due to sand recovery and processing.

The technical solution provided by the embodiments of the present application is to solve the above technical problems, and the overall idea is as follows:

The present application provides a method for surface treatment of a railway freight car, please refer to FIG1 , the method for surface treatment of a railway freight car comprises the following steps:

S1: testing the humidity and temperature of the environment in which the railway freight car is located, and when the humidity and temperature of the environment in which the railway freight car is located reach predetermined conditions, preheating the railway freight car;

S2: performing dry ice sandblasting on the railway freight car;

S3: The railway freight car is subjected to a baking treatment.

The mechanism of dry ice blasting is mainly based on heat, mechanics and expansion. Dry ice at -75℃ has a cooling effect on the surface, which causes the impurities and oxide layers attached to the surface of the substrate to shrink, become brittle and form cracks. Since the thermal expansion coefficient of these impurities is different from that of the substrate, they are partially peeled off under the action of dry ice. Moreover, when the dry ice particles enter the cracks of the dirt after impact, they are immediately vaporized, and their volume instantly expands nearly 800 times, causing a huge impact force locally, making it easy to remove the dirt. Since dry ice particles have a very low hardness compared to other solid sandblasting particles, different materials can be cleaned by adjusting parameters, and the surface of the substrate can be completely removed without damaging it.

The preheating process is to heat the surface of the railway wagon to remove water or water vapor from the surface of the railway wagon to prevent the moisture on the wagon body from freezing during the dry ice blasting process. When the humidity of the environment in which the wagon is located is low or the temperature is high, preheating is not required.

The baking process refers to the baking of railway freight cars after the surface treatment with dry ice. Its purpose is to prevent the surface temperature of the car body from being too low, generating a large amount of condensation water, and causing the car body to rust.

It should also be noted that dry ice blasting is generally carried out in a workshop. Since excessively high carbon dioxide concentrations can endanger human life, ventilation equipment should be installed in the workshop.

The present application implements dry ice sandblasting technology on railway freight cars, which is dust-free, low-noise, and has no problems of embedding into the substrate and recycling. It is also not easy to deform thin workpieces, and has the advantages of not easily causing damage to the cleaned surface, low cost, and rapid cleaning.

In some embodiments of the present application, the predetermined condition is humidity>80% or temperature<12°C.

It is easy to understand that if any one of the conditions of humidity > 80% or temperature < 12°C is met, there may be water stains on the surface of the railway freight car.

In some embodiments of the present application, the preheating temperature is 30-40°C.

It is easy to understand that a temperature of 30 to 40°C is sufficient to dry the surface of a railway freight car.

In some embodiments of the present application, the preheating time is 15 to 30 minutes.

It is easy to understand that the surface of railway freight cars is made of metal, which conducts heat quickly, and 15 to 30 minutes is enough to dry the surface of railway freight cars.

In some embodiments of the present application, the dry ice blasting is performed by a dry ice cleaning machine. During the dry ice blasting process, the working pressure of the dry ice cleaning machine is 0.2-0.4 MPa.

The main stains on the surface of railway freight cars are oil, rust, welding smoke, chalk writing, dust and other attachments. 0.2-0.4MPa is usually sufficient for cleaning.

In some embodiments of the present application, the dry ice cleaning machine includes a spray gun for spraying dry ice, the length of the spray gun is 30 to 50 cm, the nozzle diameter of the spray gun is 1 to 2 cm, and the length is 5 to 8 cm.

In some embodiments of the present application, the distance between the nozzle and the surface of the railway freight car is 5 to 20 cm.

The main stains on the surface of railway trucks are oil stains, rust, welding smoke, chalk writing, dust and other attachments. When cleaning easy-to-clean attachments such as chalk writing and dust, the distance between the nozzle and the surface of the railway truck can be appropriately increased, which can increase the cleaning area and improve the cleaning efficiency while effectively cleaning. When cleaning oil stains, rust, welding smoke and other attachments that are not easy to clean, the distance between the nozzle and the surface of the railway truck can be appropriately pulled closer to increase the impact force between the dry ice and the surface of the railway truck and enhance the cleaning effect.

In some embodiments of the present application, the baking temperature is not less than 40° C., and the baking time is not less than 30 min.

The temperature of the surface of the railway freight car after dry ice blasting is very low and needs to be baked at 40° C. for more than 30 minutes.

In some embodiments of the present application, the railway freight car is one of an open car, a box car, a flat car, a tank car, and an insulated car.

In some embodiments of the present application, the material of the truck surface is one of aluminum alloy, stainless steel and carbon steel.

The present application will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are intended only to illustrate the present application and are not intended to limit the scope of the present application. The experimental methods for which specific conditions are not specified in the following examples are usually measured according to industry standards. If there is no corresponding industry standard, then the conditions recommended by the manufacturer are followed.

Example 1

The BH1 insulation car is treated in the workshop through the following steps:

The humidity and temperature of the workshop were tested, and it was found that the workshop temperature was 2°C and the humidity was 26%, which met the condition that the temperature was less than 12°C. Therefore, the railway freight car needed to be sent to a baking room for preheating, wherein the baking room was a workshop equipped with a heating device, a blast device, and a ventilation device;

After the preheating is completed, the railway freight car is subjected to dry ice sandblasting;

After the dry ice sandblasting treatment is completed, the railway freight car is subjected to a baking treatment.

The preheating temperature is 35° C. and the preheating time is 20 min.

The dry ice blasting is performed by a dry ice cleaning machine. During the dry ice blasting process, the working pressure of the dry ice cleaning machine is 0.3 MPa.

The dry ice cleaning machine comprises a spray gun for spraying dry ice, the length of the spray gun is 35 cm, the nozzle diameter of the spray gun is 1 cm, and the length is 8 cm.

The distance between the nozzle and the surface of the railway wagon floats within 5 to 20 cm. When the stain is difficult to remove, the distance between the nozzle and the surface of the railway wagon is appropriately shortened.

The baking temperature is 40°C.

Example 2

The C70 open wagon is subjected to the following steps in the workshop for the surface treatment of railway wagons:

The humidity and temperature of the workshop were tested, and it was found that the workshop temperature was 37° C. and the humidity was 81%, which met the condition that the humidity was greater than 80%. Therefore, the railway freight car needed to be sent to a baking room for preheating, wherein the baking room was a workshop equipped with a heating device, a blast device, and a ventilation device;

After the preheating is completed, the railway freight car is subjected to dry ice sandblasting;

After the dry ice sandblasting treatment is completed, the railway freight car is subjected to a baking treatment.

The preheating temperature is 35° C. and the preheating time is 20 min.

The dry ice blasting is performed by a dry ice cleaning machine. During the dry ice blasting process, the working pressure of the dry ice cleaning machine is 0.3 MPa.

The dry ice cleaning machine comprises a spray gun for spraying dry ice, the length of the spray gun is 35 cm, the nozzle diameter of the spray gun is 1 cm, and the length is 8 cm.

The distance between the nozzle and the surface of the railway wagon floats within 5 to 20 cm. When the stain is difficult to remove, the distance between the nozzle and the surface of the railway wagon is appropriately shortened.

The baking temperature is 40° C. and the baking time is 30 minutes. The baking is carried out in a special baking room, which is equipped with a heating device, a blasting device and a ventilation device.

Example 3

The BH1 insulation car is treated in the workshop through the following steps:

The humidity and temperature of the workshop were tested, and it was found that the workshop temperature was 32° C. and the humidity was 56%, which did not reach the humidity>80% or the temperature<12° C., so there was no need to preheat the railway freight car, and the railway freight car was directly subjected to dry ice sandblasting;

After the dry ice sandblasting treatment is completed, the railway freight car is subjected to a baking treatment.

Wherein, the dry ice sandblasting is performed by a dry ice cleaning machine, and during the dry ice sandblasting process, the working pressure of the dry ice cleaning machine is 0.3 MPa.

The dry ice cleaning machine comprises a spray gun for spraying dry ice, the length of the spray gun is 35 cm, the nozzle diameter of the spray gun is 1 cm, and the length is 8 cm.

The distance between the nozzle and the surface of the railway wagon floats within 5 to 20 cm. When the stain is difficult to remove, the distance between the nozzle and the surface of the railway wagon is appropriately shortened.

The baking temperature is 40° C. and the baking time is 30 minutes. The baking room is a workshop equipped with a heating device, a blast device and a ventilation device.

Example 4

The C70 open wagon is subjected to the following steps in the workshop for the surface treatment of railway wagons:

The humidity and temperature of the workshop were tested, and it was found that the workshop temperature was 35° C. and the humidity was 76%, which did not reach the humidity>80% or the temperature<12° C., so there was no need to preheat the railway freight car, and the railway freight car was directly subjected to dry ice sandblasting;

After the dry ice sandblasting treatment is completed, the railway freight car is subjected to a baking treatment.

Wherein, the dry ice sandblasting is performed by a dry ice cleaning machine, and during the dry ice sandblasting process, the working pressure of the dry ice cleaning machine is 0.3 MPa.

The dry ice cleaning machine comprises a spray gun for spraying dry ice, the length of the spray gun is 35 cm, the nozzle diameter of the spray gun is 1 cm, and the length is 8 cm.

The distance between the nozzle and the surface of the railway wagon floats within 5 to 20 cm. When the stain is difficult to remove, the distance between the nozzle and the surface of the railway wagon is appropriately shortened.

The baking temperature is 40° C. and the baking time is 30 minutes. The baking room is a workshop equipped with a heating device, a blast device and a ventilation device.

Various embodiments of the present application may be presented in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity, and should not be understood as a rigid limitation on the scope of the present application; therefore, the range description should be considered to have specifically disclosed all possible sub-ranges and single numerical values within the range. For example, the range description from 1 to 6 should be considered to have specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5 and 6, which apply regardless of the range. In addition, whenever a numerical range is indicated herein, it is meant to include any cited number (fractional or integer) within the indicated range.

In the present application, in the absence of any contrary description, the directional words used, such as "upper" and "lower", are specifically the directions of the drawings in the accompanying drawings. In addition, in the description of the present application specification, the terms "including", "comprising", etc. refer to "including but not limited to". Moreover, the terms "including", "comprising" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or equipment. In the absence of further restrictions, the elements defined by the sentence "including..." do not exclude the existence of other identical elements in the process, method, article or equipment including the elements. In this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. In this article, "and/or" describes the association relationship of associated objects, indicating that there can be three relationships, for example, A and/or B, which can represent: A exists alone, A and B exist at the same time, and B exists alone. For the association relationship of more than three associated objects described by "and/or", it means that any one of these three associated objects can exist alone, or any at least two of them exist at the same time. For example, for A, and/or B, and/or C, it can be represented that any one of A, B, and C exists alone, or any two of them exist at the same time, or three of them exist at the same time. In this article, "at least one" refers to one or more, and "multiple" refers to two or more. "At least one", "the following at least one (individual)" or similar expressions refer to any combination of these items, including any combination of single (individual) or plural (individual). For example, "at least one (individual) of a, b, or c", or "at least one (individual) of a, b, and c", can all represent: a, b, c, a-b (i.e. a and b), a-c, b-c, or a-b-c, wherein a, b, c can be single or multiple, respectively.

The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features applied for herein.

Claims (10)

1. A method of surface treatment of a railway wagon, the method comprising the steps of:

testing the humidity and the temperature of the environment where the railway wagon is located, and preheating the railway wagon when the humidity and the temperature of the environment where the railway wagon is located reach preset conditions;

carrying out dry ice blasting treatment on the railway wagon;

And baking the railway wagon.

2. A method of surface treatment of a railway wagon according to claim 1, wherein the predetermined condition is a humidity > 80% or a temperature < 12 ℃.

3. A method of surface treatment of a railway wagon according to claim 1, wherein the preheating is at a temperature of 30-40 ℃.

4. A method of surface treatment of a railway wagon according to claim 1, wherein the preheating time is 15-30 min.

5. A method for surface treatment of railway freight car according to claim 1, characterized in that the dry ice blasting is performed by a dry ice cleaning machine, and the working pressure of the dry ice cleaning machine is 0.2-0.4 MPa during the dry ice blasting.

6. A method of surface treatment of a railway wagon according to claim 5, wherein the dry ice cleaning machine comprises a spray gun for spraying dry ice, the spray gun having a length of 30-50 cm, a nozzle diameter of 1-2 cm and a length of 5-8 cm.

7. A method of surface treatment of a railway wagon according to claim 6, wherein the distance of the nozzle from the surface of the railway wagon is 5-20 cm.

8. A method of surface treatment of a railway wagon according to claim 1, wherein the temperature of the baking is not lower than 40 ℃, and the time of the baking is not lower than 30min.

9. A method of surface treatment of a railway wagon according to claim 1, wherein the railway wagon is one of a truck, box wagon, flatcar, tank wagon, and insulated wagon.

10. A method of surface treatment of a railway wagon according to claim 1, wherein the wagon surface is made of one of an aluminum alloy, stainless steel and carbon steel.