Crimping rods ROSTAR

/ Rostar / About / News / Crimping rods ROSTAR
Crimping rods ROSTAR
Research-and-production association Rostar increases manufacture of a new modification of rods crimping, of original design, which wins more and more popularity among consumers. Difference between the rods, manufactured before, and the new ones, is explained by chief constructor of Research-and production association Rostar Sergey Chupin. - Lets specify, why is it a new modification of rods? - There is a principal difference between old rods and new ones. The new rods represent an engineering change and, accordingly, connected with it change of the manufacture method. In general, all the rods can be manufactured with several methods: either single-part forging or casting, or assembly from the tube and the end by welding or crimping. There exist also regulated rods, using threaded coupling. In this case a new set of rods is the transition from solid-forged production to crimping technology of rod manufacture. For manufacture of the rod we use the method of hot crimping. Connection between the tube and the end is performed by crimping with preliminary heating of the tube. With such a technology the tensile strength and rupture strength of the connection is increased by several times. Due to this, we have reduced the mass of the rod itself by 15%, and, avoiding the manufacturers of forgings, quality of which is hard to be controlled, we have improved the quality of the product. We have mastered the full manufacture cycle of rods production. We also manufacture the forgings of ends, get from the suppliers a qualified tube and fully control the process of part manufacture. Meanwhile, adoption of new technology doesnt reduce the reliability of the rod, its working life, and even by some parameters raises it. And due to the fact, that the rod became lighter, the total unsprung mass of the auto is reduced, the consumer properties are improved. - Is it your original development? - We cant state, that the crimping rods were invented by specialists of Rostar, as it is a well-known construction. It has been already used for a log time in Europe and today 79-80% of rods are crimping there. We also start to pass on to this technology, because its more efficient. - What can you say , based on the experience of exploitation of such rods? - They can calculate money in Europe, and their experience has shown, that such rods in exploitation with their characteristics are not inferior to single-part forged constructions. At the same time they are easier to produce and cheaper. Sure, for adopting a new manufacture line, we had to purchase heavy presses, and first we considered the variants of cold crimping. But as a result of experiments we came to the conclusion, that it is better to use the method of hot crimping, thats why we bought the additional equipment for organization of technical process. Though the investments into preparation of manufacture line have risen, it was worth doing, because Rostar doesnt save on the quality. - Which constructive advantages of the set of crimping rods ROSTAR would you mention? - An important constructive advantage of many our rods is fastening of rubber-metallic joint, which is performed with the lid on the bolt clamp. European manufacturers mainly press rubber-metallic joint with the help of special press and then the retaining ring is installed. With our construction, due to the fact, that the lid can be turned off with the regular spanner wrench and the driver can replace the rubber-metallic joint almost in the field, the repairability of rods gets higher. And this can be considered as constructive advantage of our rods. Though the method of hot crimping is not our know-how, not all the manufacturers apply it. We have made many investigations and experiments, in order to find an ideal profile of the wave and heating temperature, by which ideal crimping takes place and maximal durable connection is achieved. It is very important to find such a point of heating, by which the metal doesn't lose its qualities. - For which automobiles do you already produce rods of this new modification? - Mainly, the smooth transition with rods for the whole scale of commercial trucks is taking place now. KAMAZ is now transferring to crimping rods, their advantages and saving were appraised. With the time, I think, all the trucks manufacturers will follow this example.

07.08.2011