These chains are made of hot rolled round bars supplied in coils. The coils are subject to pickling and calibration in a special workshop section and then delivered to the welding area.
Chain production lines are comprised of automatic chain-bending and welding machines. The machines feature electronic control with a wide selection of modes ensuring optimal set-ups to obtain high-quality chains.
The chain-bending machine bends chain links from coiled bars and provides for link edges preparation to obtain high-quality welded joints.
Butt welding is performed by the chain-welding machine using resistance welding method.
In this process the link ends are butt joined under pressure before being heated. Then current is switched and the link ends are heated to the ductility temperature.
After that a sharp upsetting is performed resulting in a permanent welded joint. We use equipment of global brands to achieve high quality of bending and welding.
The chains are made of hot rolled steel rods.
The rods are delivered to the blank section, where they are cut into blanks using up-to-date steel cutting tools for subsequent chain welding. A blank may be produced by the following methods: bundle cutting by the band saw with high-quality edge surface, high speed cutting by the circular saw and hydraulic press cutting with lower blank deformation.
After that the blank is sent to shot-blasting or barrelling.
Large-size chains are welded using special welding equipment providing for the full cycle of bending, welding and studding, if necessary. Precut blanks are heated up to about 800 °C, then sent to the link bending section and further to the link welding section. Chains with diameter above 20 mm are welded by straight flash method. Electric current goes through the chain link until its ends join. Steel in the contact area heats up to the melting point and splashes in the form of sparks cleaning the weld and eliminating surface irregularities.
At the final stage the link is upset under high pressure to obtain clear welded connection. Precise adjustment of upsetting force enables us to obtain a joint of perfect quality.
Accessories are manufactured by hot die forging.
Forging is performed on precut round blanks sent to the forging workshop from the blank section.
The forging workshop uses special forging lines consisting of induction heating installations for blank heating up to 1200 °C, preforming hydraulic presses, die-forging hammers and deburring press tools.
We can obtain high-precision articles with required surface quality and mechanical characteristics with minimum machining. This has a positive effect on the price of finished products. Combining forging on high-performance hydraulic hammers with own manufacturing of forging rigging enables us to produce large batches of products and quickly modify product design if necessary.
Heat treatment of chains is performed in furnaces of various types: batch-type, pit-type with a possibility of blanketing, and induction furnaces. For example, after heat treatment by carburizing, nitriding and nitrocarburizing chains become abrasion resistant.
Through-type induction furnaces along with standard heat treatment offer the option of obtaining links with different hardness of the articulation area and of the straight sections.
Thus chains reach higher abrasion resistance while keeping their strength characteristics on the same level.
All our products are subject to strict controlling at each production stage. Comprehensive analysis is performed by an independent laboratory: raw material control, process monitoring and finished product parameters control.
During the tests all possible types of impact, that can appear during operation, are simulated. An integrated control and process automation system guarantees high quality of our products at all times.
Only the products that have passed through the strict quality control are approved for supply to our customers. A decision on releasing the product for sales is taken only when there are no comments on the production process and quality of finished product.
All the products are certified and released in full compliance with the requirements of regulatory technical documentation.
