Innovative design of machine steelIn 2014, Neka Machine Steel Industries took a new step in the machinery industry and the production of heavy equipment by designing a new type of overhead crane. The structure of this innovative crane is made using hollow steel sections, which are the products of this company.
Mechanical changes occur in the following two cases:
- Use HSS cross section with high strength steel
- Ease of construction of crane structure
- Wheels and force position
- Connect the conductor to the main structure of the crane (bridge)
Innovative steel crane roof components
Use of HSS sections with high-strength steel
In conventional cranes, it is not possible to integrate the main structure of the crane, because steel plate is used in the construction of the main structure of these cranes. And usually the dimensions of the plates available in the market are a maximum of 1.5 x 6 meters. So, for example, in a structure with a span of 20 meters, to make a life or a wing box in these dimensions, it is necessary to assemble four pieces of plate. This means that structures that are made with a box in the form of a plate have disadvantages such as the large volume of welding, the complexity and radiance of the weld, and the fragmentation of the main structure. However, in the structure of the roof cranes of Machine Steel Company, which are truss models, it is made of HSS structural sections. These sections are semi-prefabricated, which has a lower welding volume than conventional structures and at the same time makes it much shorter. Due to the continuous production process of these sections and if there is no restriction on transportation, it is possible to produce these longitudinal sections in an integrated manner and during the desired length. Also, the steel used in this structure is made of high-strength steel, which makes the structure lighter and therefore its control is better (due to the inertia and kinetic energy of the crane along the shed). It also makes the structure more economical.
Ease of construction of crane structure
Unique innovation and mechanism in the mechanical part of this crane and as a result the use of simple and available tools and equipment at a reasonable price in The crane, as well as the production of sections from a reputable manufacturer, has made it easier to build and less expensive than conventional cranes.
Wheels and position of force
Another difference of this crane compared to conventional models is in the wheels, the position of the force exerted and the guides. It is possible that they have a life in the middle of the beam. In each axis, we can install a wheel in the middle. Be.
Innovative steel machine
In the truss model crane made by Foolad Machine Company, due to the use of HSS sections with high-strength steel (St 52) in the beams of the cranes and having two souls, we have the possibility of installing two wheels in each axis.
These wheels are in the corners of the beam The cranes are housed in the HSS rectangular section, which is the strongest position of the box. Therefore, they do not need to use separate rails. Also, because these boxes are made by machine, they are much more accurate and beautiful, and in addition, it is expected that its cost will be cheaper than the usual H-type crane beams. As the number of wheels increases from two to four, the amount of load applied to each wheel is reduced by half, which means that the wheels and beams of the cranes work at half the design capacity, and basically equipment with lower working capacity. They will have a much longer lifespan.
The impact of the crane bridge on the guide beams
Another point in the difference in the mechanism of these two cranes is the type of connection of the guides to the bridge. In conventional models, this connection is of the rigid or clamped type and is connected to the bridge by a flange. This rise produces a rotational force or anchor in the conductors of the sides, and due to the variability of the gravitational load, the bridge rise is constantly changing, so the wheels are slightly detached from their bed and do not lie evenly on the bridge, which is It leads to crushing, abrasion and change in the shape of the wheels and will lead to long-term depreciation of the structure.
ابداعی فولاد ماشین
However, in the new mechanism introduced by Machine Steel Company, the connection of the conductor to the bridge is of the articulated type, as a result of which the position of the wheels in relation to the crane beam always remains constant. Sit evenly in their bed.
Another noteworthy point that is the result of using this new system is the discussion of the noise and vibration of the crane, which due to the lower weight and self-adapting mechanism of the wheels makes the crane move very soft, without Noise and free from the usual vibrations of overhead cranes. Also, the design and construction of these cranes can be implemented in different openings and capacities without any restrictions. This truss structure is more economical in larger openings than other advantages of this crane.
The order of each component of the crane is based on the customer's request and the requested brand. These parts and equipment include various types of control panels, various types of lifts, longitudinal and transverse motion gearbox motors, longitudinal and transverse power supply systems (open / closed shin types, C-rails, electrical panels), etc.
Another is to have a self-alignment system in each leader and elevator trolley. Due to the articulated connection of the conductor to the bridge, in the event of an error or unevenness in the turrets or the mismatch of the axes, the conductors adapt to the existing fault, which in fact causes uniform dead and live load distribution of the crane and applying equal pressure to The wheels eventually increase the life of the wheels, axles and turrets.In hard-to-connect cranes, due to the lack of a self-adapting system, in the event of a complete mismatch of the turrets along the path, the structure will be subjected to severe stresses to adapt, which will eventually be repeated. Fatigue and radiance become the main structure. It should be noted that these tensions occur in two ways:
If the crane is not loaded enough, it will not twist, in which case one or two wheels will be detached from the bed and will remain in the air. By applying force, the load distribution between the wheels becomes uneven, the force applied to the wheel on the opposite side is reduced, and the additional force is imposed on the wheel under load application.
If the maximum load capacity of the crane or more than 40-30% of the load capacity is applied, then the wheel or wheels suspended and separated from the bed, under the force of the applied pressure, will inevitably be placed on their bed and subsequently the whole structure. It undergoes a twist around its longitudinal axis (chocolate), which causes significant stress to most of the elements and the body of the structure itself at the junction.
In the crankshaft of common cranes, as the main structure of the crane is the box-built-up, and due to the lack of life in the middle, the rails must be placed on the inner soul of the box, in which case by applying force F, one Rotation torque will occur in the box section relative to its longitudinal axis.
But in the innovative design of Machine Steel Company, using HSS sections with two lives, in a lifting trolley, it will be possible to add two other wheels like the guides, which is the rotational force of the box section rotation around the axis. It will eliminate the longitudinal and asymmetrical force applied to the structure. In fact, in addition to the benefits that guides have, the lifting trolley also has this added advantage.