In 2011, the plant produced and delivered a special sea loader intended to load fertilizers aboard sea vessels to “NIKA-TERA” seaport in Nikolayev. The loader’s capacity is up to 1500 tons per hour. The overall weight of loader’s metal is 260 tons.
The loader consists of a great number of bulky knots: trunk boot mechanism, rotator, bearing rockers, arrow metal constructions, rear conveyor metal constructions, rotator bridge, etc., transported by special motor transport to the seaport of Nikolayev to the assembly place.
|Control assembly of loader’s bulky knots: rotator, cross, rockers and ring with the rail||Loader during the assembly. “NIKA-TERA” port, Nikolayev|
Subassemblies meet tough requirements due to geometrical dimensions and shape in order to minimize pressure. Loader’s subassemblies consist of a great number of parts interconnected with fusion welding method. Thickness of rolled metal is up to 20 mm, edges cutting for welding, guaranteed gaps to ensure 100% foundering, as well as large dimensions of welds are the cause of plastic deformation of welds and weld metal zones resulting in their buckling. In order to avoid welds buckling, the plant’s product engineers use a complex approach. That is: welds are made strictly due to the developed scheme, with the smallest cross-section rolls at the increased welding heat input; cutting of long-haul welds edges is filled due to the “cascade” and “slide” scheme with thread welds of up to 300 mm long. After filling one-third of welds amount, welds are handled with blunt striker hammer; after filling all welds, they are handled with vibration resonance installation to relax peak residual stress in the weld metal zone. In order to prevent plastic deformation, subassemblies before welding are strictly positioned on gas stoves, and some parts are assembled and welded in conductors and in specially designed welding rooms.
Welding is conducted by attested welders under general guidance of the plant’s chief welder due to technological process attested by the Expert Technical Center. In order to minimize welds flaws, automatic welding under flux layer, as well as semi-automatic electric-arc welding in the protective gas medium, is used.
In this case, coppered or polished welding wire is used, and “Mix-2” gas mixture is applied as protective gas. The use of Ar+CO2+O2 gas mixture has allowed increasing welds density and decreasing deformation after welding. Welds quality is controlled by visual optical method, ultra sound
flaw detection, capillary methods, as well as magnetic particle inspection. The control is conducted by NDT inspectors attested for the second level of accreditation with the right to issue conclusions of testing results.
Welds of the most important assemblies were subjected to local heat treatment. The control of welds was conducted before and after heat treatment. After TCI taking all parts and assemblies, the loader passed through commission acceptance tests. Multi-stage control and the existing quality system allowed producing a reliable and quality loader.
The plant uses the similar approaches to produce the whole product nomenclature. It is necessary to mark the plant’s technological opportunities of producing the following parts and subassemblies of lifting equipment: pinion shaft, gears, screws, lifting drums, etc. High qualifications of working and engineering staff, as well ad equipment attested for its technological accuracy, are necessary to produce such parts and subassemblies. PJSC “Azov machine-building plant” has all the resources, as well as enough gas stoves, universal and specialized equipment, instrumentation to assemble and weld in parallel all the metal constructions of lifting equipment. The figures show assembly of overhead crane main beam apertures, assembly and welding of overhead crane main beam, drilling of holes on crane trolley beam and assembly of overhead crane end girders.
Overall dimensions of assembly shop transverse span allow conducting control assembly of the whole unit. The figure shows the control assembly of special electric overhead crane bridge with span width of 34 m and lifting capacity 20 tons, made and delivered by RAO “UES”.
The availability of railway drive and opportunities of lifting equipment of assembly and welding shop allow loading bulky metal constructions onto railway platforms.
It is necessary to mark unique possibilities of PJSC “Azov machine-building plant” to transport bulky metal constructions via Berdyansk seaport: to the industrial districts of the Urals, using the Don – the Volga-Don canal route, including the Volga inflows; to the oil and gas production areas of the Caspian basin; to Europe via the Black Sea and the Mediterranean Sea, as well as to Southern and Eastern Europe down the Danube.