El trueque es el presente y el futuro del comercio internacional, especialmente para las personas que se inician en el negocio de importación y exportación. El trueque y más, operaciones triangulares.
La segmentación perfecta para sus propuestas de negocio, Sus lugares de destino, además de su clase de clientes objetivo, además de sus artículos y categorías.
The main function of the connecting head of the hydraulic support is to connect the scraper conveyor and the hydraulic support organically to realize the effect of force transmission between them.
At work, connecting head to operate mobile scaffold and push conveyor connection effect, therefore, the connection head in addition to withstand normal also twisted the alternating stress of tension and compression, combined with the underground work environment is poor, and the moisture in the air, and there may be many unexpected factors, lead to the connection head the situation worse. Once the connection head is damaged, the scraper conveyor and hydraulic support may not work normally, and the production may stop due to the shutdown, causing huge losses. So the quality of the hydraulic support connection is particularly important, in the choice of manufacturers, production process, material to be carefully selected, to reduce the possibility of the above situation.
Casting steel structure is mostly used in daily connection, which has the advantages of reliable connection and convenient manufacture. But cast steel also has a big problem, that is, in the process of smelting and crystallization, the inherent unevenness. Many studies have shown that such inhomogeneity can effectively improve the bending strength and hardness of the material under certain conditions, but deteriorate the toughness and plasticity of the casting, and even reduce the tensile strength of the casting, which is bound to result in the failure of the casting to give full play to the potential properties of the metal material in use. In many mines, the use of this type of joint head, after a large impact, hard roof under the load conditions, will lead to a serious fracture phenomenon of the joint head, will affect the normal production. Therefore, according to customer demand, there are die forging and free forging to enhance the toughness of the joint.
