Cylinders for storing various gases, including carbon dioxide, are sold empty. The cylinder itself is a metal tank, sometimes a plastic one. It is worth noting that the metal material for the manufacture of the container is preferable to the plastic, since no static stress is formed on its walls.
Cylinder device
A carbon dioxide cylinder is a container made of metal in the form of a cylinder, which has a thread with a screw-in shut-off valve in the upper part of the device. It is important to note that the type of shut-off valve will depend on the gas with which it is filled. Separate high demands are placed on the tightness and reliability of gas cylinders, especially with substances such as carbon dioxide.
You can also add that the valve design for a carbon dioxide cylinder has not one, but three threads. The bottom is designed to fix it in the tank itself. The valve stem is attached to the upper thread, and the side is intended for the plug.
Types of cylinders
It is important to understand that one of the features of these containers is their diversity. There are metal and composite cylinders, as well as gas cartridges. Of course, the most common type is a metal bottle. Its advantage is profitability. The body of this cylinder consists of either low carbon or alloy steel. Also attracted by a large selection of volume for gas storage. The volume of the carbon dioxide cylinder can be 5, 10, 12, 20, 27, 40, 50 liters.
It is important to note that the storage of a fifty-liter cylinder is allowed only on the street in a special cabinet, as well as with special markings. Since the containers are made of metal, their mass is quite large, even if they are empty. The weight of one empty cylinder is in the range from 4 to 22 kg and depends on the displacement.
One important point - metal tanks are most often designed to store or transport a large volume of carbon dioxide. If the amount of substance is small, it is better to choose a composite container as a storage. The main advantage of this type of tank is the lower weight of the tank itself. The weight of a carbon dioxide composite cylinder will be about 70% less than that of a metal one.
GOST containers
According to GOST 949-73, the volumes for CO2 cylinders are 5, 10 and 40 liters. They are used for storage, transportation and distribution of gas to consumers. These devices should include the following parts:
- VK oxygen valve with a mass of 0.5 kg;
- transport rubber ring in the amount of 2 pieces;
- support shoe weighing 5.2 kg;
- steel or recertified hood, the weight of which is 1.8 kg, or the same part, but made of fiberglass weighing 0.5 kg;
- a ring that is worn on a neck weighing 0.3 kg.
The production of carbon dioxide metal cylinders should be carried out only from steel grade 45 D or steel grade 40 X GSA, if this is a capacity of 40 liters.
Features of the cylinder with CO2
The carbon dioxide cylinder must be completely painted black, and also have the inscription "CARBON ACID" made of yellow enamel. It is worth noting that the weight of the tank is set without taking into account such details as a valve, rings, caps, shoes. In addition to coloring and inscriptions, the tank must contain passport information about it.
The application of these data is carried out by the shock method. It is important to know that the information is applied in the upper part of the container, and its location is completely cleaned to a metallic luster and has a highlight 20–25 mm wide in yellow. Here is a list of the information that the passport should contain:
- date of production of the tank and year of subsequent inspection;
- what pressure of carbon dioxide in the cylinder (indicated in MPa (kgf / cm 2 );
- tank capacity (indicated in liters);
- empty tank weight (indicated in kilograms);
- serial number of the tank and brand of the company that manufactured it;
- brand of the company that conducted the technical survey;
- the latest stigma from the technical control unit of the company that manufactured the tank.
Technical specifications
Depending on the capacity of the tank, various technical requirements are presented to it. If the tank is produced in a volume of 5 liters, then the grade of steel that should be used for its production is 45 D. The pressure of carbon dioxide in a cylinder with such a volume should be 14.7 MPa (kgf / cm 2 ). The diameter of such a cylindrical container is 140 mm, the length is 475 mm, and the weight is 8.5 kg.
The manufacture of cylinders with a capacity of 10 liters is carried out from the same steel grade as 5 liter. The pressure in such tanks as their diameter also corresponds to the previous type. The length of such a cylinder should be 865 mm, and weight 8.5 kg.
A 40-liter carbon dioxide cylinder can be made of steel grade 45 D or steel 40 X GSA. If production is carried out from the first grade of steel, then the pressure in it also remains at the level of 14.7 MPa (kgf / cm 2 ), and if from steel 40 X GSA, then the working pressure increases to 19.5 MPa (kgf / cm 2 ) . The diameter of both gas tanks will be 219 mm. The length of the cylinder made of steel 45 D will be equal to 1370 mm, and of steel 40 X GSA 1350 mm. The mass of the tank from the first steel grade is 58.5 kg, and from the second - 51.5 kg.
Cylinder application
The following are some areas of application for these CO2 tanks.
- In medicine, they are used during freezing in the operating unit.
- In the food industry they are used in the production of carbonated drinks, as well as some cocktails.
- They are also used in the perfume industry in order to obtain perfumes with a rich aroma and without an unpleasant, specific smell.
- Of course, they are used during construction or repair work during welding of a structure where the formation of additional soot cannot be allowed.
It is also worth noting that conventionally all carbon dioxide cylinders are divided into three categories. The first includes small containers - 2, 5, 10 liters. The second includes medium tanks from 20 to 40 liters, and the third large ones - from 40 liters or more. Demand for each category depends on the scope of their use. For example, medium and large cylinders are used in industrial sectors, since they do not need to be refilled too often. It is important to note that each tank must pass certification every 5 years.
Pressure parameters
When operating these tanks, it is important to know that they have two pressure indicators. The first indicator is the working pressure, which, subject to all the rules of operation and transportation of the tank, should not go beyond 150 bar. The second type of pressure is the test pressure, which acquires great importance during the stage of connecting the main system. This parameter should not be higher than 225 Atm. It is also worth noting that when ordering these containers, you need to make sure that you have a protective cap.
It can be added that after some chemical studies, as well as laboratory observations, it was found that CO2 in the tank is the safest gas of all, and therefore it can be used in open areas.
Gas characteristic in a cylinder
You can start with the fact that the cost of this substance is quite small. This product does not have any color and is not poisonous. Carbon dioxide is obtained in the process of burning coal fuel, gaseous wastes from the alcohol and sugar industries. When the temperature of carbon dioxide in the tank is +31 degrees Celsius and a pressure of 75.3 Atm, this substance is liquefied. With decreasing temperature, the liquefaction pressure will also decrease.
It is important to note that at a temperature of -78.5 degrees Celsius, this substance will begin to transition from a gaseous to a liquid state. During the evaporation of 1 kg of liquid, 505 liters of gas will be obtained. It is also important to note that during storage and transportation this product is in a liquid state under a pressure of 60-70 Atm. Another important fact is that only 25 kg of liquid carbon dioxide is contained in a cylinder of 40 liters. Upon evaporation of the entire volume of liquid, 12,600 liters of gas will be obtained.
Carbon Filling
In order to fill the tank with gas, several methods can be used. The first method is the transfer of substance from one cylinder to another. In order to carry out this process, it is necessary to use specialized equipment, as well as adapters. The most important point when refueling is weighing the tank, as this is the only way to determine how much substance was inside after refueling.
You can use specialized installations for pumping gas using a compressor to refuel a carbon dioxide cylinder. This method is considered more relevant, as it provides a more accurate gas filling of the cylinder, and also minimizes the loss of substance during this operation. In order to understand how filled the cylinder is, it is also necessary to use container weighing.
It is worth noting that for the refueling process, it is necessary to turn the container, which is the donor, down the valve so that it is as close to the floor as possible. After that, a high pressure hose is screwed to it, which will be the conductor of the substance from one tank to another.