Yevhen Bilytskyi


Yevhen Bilytskyi

Welding Faculty, NTUU ‘KPI’

The possibilities of welding equipment application with the synergistic regulation without trim-regulation, compliance with the geometric size of the welded joints according to the requirements of HOST14771-76 is verified, speed range in which feedback provides the qualitative formation of the weld bead is investigated.

In modern welding production, the welding with the consumable electrode in shielded metal arc welding occupies a leading position among other arc processes. The rapid development of power electronics has led to the appearance of new welding equipment with new functionalities, thanks to the power supplies of synergistic regulation systems of welding.

The aim of this work was to solve the following problems:

1. Check the applicability of welding equipment with the synergistic control without fine tuning of the profile (trim-regulation).

2. Perform welding in modes designed for geometrical dimensions of the weld and the regulations proposed by the built-in power supply of synergistic algorithms.

3. Check the speed range in which the geometric dimensions of the weld will meet the requirements of HOST14771-76. Welding was performed by the Fronius Vario Synergic 4000-2 automatic welding machine. For the experiments we used a mild steel plate with a thickness of 2 mm, composed according to weld with a gap of 2 mm. Preparation of plates for welding requires no bevel edges. Welding took place in one pass. As the shielding gas carbon dioxide of the 1st grade was used.

The well-known method for calculating of the geometric dimensions of the weld [1] involves the selecting of a welding wire diameter obtained by estimation of the calculated value to the appropriate standard diameter of the wire. The weld wire of the 1.0 and 1.2 mm diameter is suitable for this type and was selected for welding experiments. However, the practical part of the experiments consisted of two series of experiments:

1.     Welding on modes calculated according to the method of [1];

2.     Welding on modes built in power supply of synergistic algorithms.

The following conclusions were made as a result of the series of experiments:

1. It is established that calculated according to the method [1] the modes of arc welding in carbon dioxide of 2 mm thick steel plates, do not guarantee the formation of high quality welds.

2. Parameters of welding that were offered to be built in the source of control FroniusVarioSynergic4000-2alhorytmom synergic welding allow you to receive welds with geometric dimensions that meet the requirements of HOST 14771-76.

3. Optimization of welding: the rate of 25m/h is optimal for welding plates of 1.0 mm diameter wire thickness. Thus, welding of plates of 2 mm diameter wire thickness is advisable to conduct with a welding rate 34m/h, if the diameter of the wire is 1,2 mm which improves the performance of welding by twice in comparison with the base option.


1.Коринец И.Ф. (1998). Разработка инженерных методов расчета режимов дуговой сварки. Киев: ИЭС им. Е.О.Патона. 80-86.

2. Site welding works.



Yevhen Bilytskiy

Welding Department NTUU ‘KPI’

Hollow charge shells invention initiated the search for anti-cumulative protection. The operating principle of hollow charge shell is the formation of a thin cumulativejet of deformed metal which,facing thearmor interacts with it not as a solid body with a solid onebut as liquid with a liquid one. The high penetration of hollow charge shells is closely connected with this feature.

Along with the improvement of hollow charge shells the development of anti-cumulative protection took place. It should be noted that there are active and passive protections. Slat armor, which will be discussed belowbelongs to passive protection. The principle of operation of the grid is that the cumulative projectile that falls into it, is deforming with the help of grid facets, thus disrupting the shaped charge of the warhead by either crushing it, preventing optimal detonation from occurring, or by damaging the fusing mechanism.

Initially, grids from steel bands, fittings, wire, chains and other scrap materialswere used as passive protection. Practice has shown that they were not equally effective and their form, the angle to the horizontal frequency and bars compactness are very important.Firing of rectangular cells of different sizes showed that the most effective grid is with a cell size of 160х50mm. The material and the heat treatment used had the great influence on the stability of the grid. The best material for slat armor manufacturing is ultra-strong steel, but in most of the cases it has poor weldability.

We have developed a set of technical documentation and produced the first industrial design of new slat armor against cumulative projectiles. During the design and manufacturing the results of experiments on their effectiveness through firing in the field were taken into account. Currently,the workson optimization of the grids design and manufacturing processes are proceeding and testing of new designs and technological solutions are conducting as well.


1.Wikipedia (2014). High-explosive anti-tank warhead. Available: Last accessed 02nd Nov 2014.