Almost everything has changed since the time the pipes were applied initially. The range of their use has become large-scale, more building materials for production have appeared. What remains constant is the need to dock pipes when creating welded joints.
The scheme of the welding electrode.
The costs of welding electrodes affect the duration of the welding equipment, the productivity of the welds. The electrode, which is already spent, should be changed to another source of the filler element. Therefore, professional pipe welders should keep a sufficient number of electrodes with them.
How are welding electrodes used
When selecting the electrodes, the following is required:
- what composition has their core coating;
- what will be the consumption of rods;
- core surfacing index.
There was a mass of special devices that allow the connection of pipe fittings. They are used for different types of pipelines. Some of them have appeared recently, others have undergone significant improvements.
The table of coefficients of consumption of electrodes in relation to the brands of electrodes.
If we are talking about the processing of pipeline valves, we usually mean the process of their welding with the use of special equipment.
For welding pipe fittings with the largest size of wall thickness, electrodes are used, which are rods of metal with a protective coating.
They have a relatively low cost based on the total estimate of materials, but it is necessary to correctly determine their required volume for procurement.Back to table of contents
How to correctly determine the consumption of welding electrodes for connecting pipes
Despite the cheapness of the electrode rod has a great influence on the process of performing work, especially on its duration. If the electrode is burned out, it must be replaced with a new one, which must be installed in its original place. This procedure will require a lot of time.
Performing a total amount of work requires several hundred operations. When in the course of work there is a shortage of a certain number of electrodes, they will need to be purchased separately. It is possible that the acquisition of electrodes will be delayed, so an accurate counting of the electrodes will allow you to perfectly plan the entire process of work. The prepared electrodes should be processed by calcining them for at least 1.5-2 hours in a special dryer.Back to table of contents
What characteristics should be guided for correct calculations
To determine the consumption of rods use the input parameters:
- Mass of surfacing rod.
- The size of the weld.
- The rate of consumption of rods.
- The rate of consumption of rods for 1 p. m docking seam.
Table of the types of electrodes.
Under the weight of the surfacing refers to the weight of the part of the metal, which must fill the connecting seam. For accurate calculations of this value, you can use the technological map associated with the implementation of welding. In accordance with a rough calculation, the fraction of the mass of the surfacing of the total weight of a metal structure is 1–1.5%. An increase in the parameter may result in an overrun of the number of rods, and a decrease in the result in a lack of strength of the seams.
The overall dimensions of the seam, that is, its length over the entire length of the joint, are measured with a tape measure. The result is multiplied by the total number of seams in the section obtained, since the welding of deep joints is performed by 2-3 seams, applied in a parallel and sequential manner.
Among the applied consumption rates emit:
- Operating room
The calculation of the operating standard is based on the type of welding operation being performed. The nodal consumption rate is calculated on the basis of the deposited mass during welding of a specific construction site made of metal. The detailed consumption rate is calculated on the basis of the deposited mass during welding of the part; the influence of the technological process must be taken into account.Back to table of contents
How to theoretically determine the consumption of electrodes when welding pipes
Since pipe fittings have a known diameter size, using a geometric formula for the circumference, a specific length is calculated. With the largest size of the wall thickness of pipe fittings, you can multiply the obtained value of the circumference length by the number of passes of the electrode, which is usually 2-3.
It is necessary to calculate the consumption rate for one meter of the seam, dividing the result by the weight of the rod. As a result, the consumption rate will be obtained, expressed not in kilograms, but in pieces. Then the piece rate is multiplied by the meter, rounding it in the greatest direction to the whole value. To determine this norm should be based on the mass of the metal that is deposited. The result is measured in kilograms by multiplying the volume of the section (1 meter) by the density of the metal. The result should be increased 1.4-1.8 times, taking into account the correction for the formation of the candle from the used rod. To search for specific numbers use directories.
The formula used when counting electrodes is as follows: H = M * k.
Where H is the value of the consumption rate per 1 meter of the weld, and M is the value of the mass of the directional metal in the seam, and k is the size of the coefficient of corrections for the formation of the calcine from the used rod.Back to table of contents
How to determine the consumption of rods during welding in a practical way
It is possible that carrying out complex calculations will be difficult, so it is best to use a method that allows you to determine the consumption of electrodes according to a specific method. It is necessary to take two metal parts, as well as the electrode of the desired type.
Placement of all parts for welding is performed in the required position on a special table. For certain welding operations, the specific position of the parts is characteristic. It is necessary to simulate the conditions under which the lower, vertical or ceiling joint will be formed. After that, it is necessary to measure the length of the resulting weld, if one rod is used.
Further, the length of the weld from a single electrode should be measured, which is compared to the total size of the length of the welds. In this case, you can go to the required number of rods. The result must be accurate. At the same time, all deviations between practical and theoretical results will be insignificant.