As the main equipment in mines, heavy duty apron feeder often reduce lifetime due to the following reasons at work. 1. Surface abrasion is caused by its long - term contact with iron ore friction. 2. The plastic deformation of the surface of the heavy duty apron feeder is bumped and extruded by iron ore fallen from iron orifice. 3. The large gap generated by the wear of the guard plate causes the ore to slide out from the trough plate and fall into the sprocket shaft shoulder, which not only chafes against the shaft shoulder and causes the shaft shoulder wear, but also causes the chain plate to deviate and accelerates the shaft shoulder to wear.

The scheme of extending the lifetime of heavy duty apron feeder
The surface wear resistance, bearing capacity and shaft shoulder wear resistance of heavy duty apron feeder will be strengthened by formulating the scheme of using welding method address the above problems of device. Surfacing welding on the surface of heavy duty apron feeder can improve the surface working performance of the equipment with the following two schemes. The first scheme is to weld parallel, equidistant, narrow strip wearing layer along the length of each scraping belt on the groove plate to improve the wear resistance of the surface. The second scheme is to extend the service life of the groove plate by welding the steel strip on the length of the groove plate so that the ore does not contact directly with the groove plate. In the implementation process, the first scheme ensures that the heavy duty apron feeder has higher wear resistance and strength, and the service life is improved. But multiple layers of surfacing requires a lot of expensive hard surfacing electrode, which increases the cost. Although the second scheme saves the manufacturing cost with the low price steel narrow strip, due to its low mechanical property, poor plasticity and toughness, the high wear resistance and strength of heavy duty apron feeder is difficult to ensure, which has short service life and increased the number of maintenance, not only waste of manpower and material resources, but also reduce the operation efficiency of the crusher.
In view of the defects of the above two schemes, the operating conditions and source of damage of heavy duty apron feeder are analyzed, the improvement measures are put forward to save the cost and ensure the strength of the heavy duty apron feeder and prolong the service life of the machine. It is the third scheme that the narrow strip wearing layer of the first scheme and the steel narrow strip of the second scheme are changed into compound material narrow strip. The manufacturing process of composite narrow strips is as follows: first, the narrow strips of the same shape and size as the steel narrow strips in the second scheme are made and welded on the chain plate and groove plate respectively. Then use the hard surfacing welding electrode in the surface of the narrow strip wearing layer, and welding do not input too much heat, control the temperature between layers, so as not to produce deformation and peeling phenomenon. Compared with the first scheme, the third scheme can save 1 times of wear-resistant materials, which can prolong the lifetime of heavy duty apron feeder and reduce the cost. Compared with the second scheme, the third scheme can realize that the groove plate of heavy duty apron feeder has higher strength, and thinner the wear layer,which can improve the wear resistance of the heavy duty apron feeder and prolong its service life obviously.
The function of guard plate in heavy duty apron feeder is to prevent ore from sliding out of the groove plate. However, after using the guard plate for a period of time, wear often occurs from the bottom. When the wear reaches a certain extent, the gap between the guard plate and the groove plate becomes larger, and the ore passes through the gap and falls down from the groove plate. Friction between the ore and the shaft shoulder causes wear on the shaft shoulder. In addition, ore fall behind the shaft shoulder will also cause the chain plate off track and accelerate the shaft shoulder wear. In dealing with the wear of the shaft shoulder, surfacing electrode is used to restore the size of the shaft shoulder. However, although the welding rod has a higher strength, toughness and crack resistance, its surface wear resistance can not meet the requirements of the shaft shoulder position on the wear resistance, so although the shaft shoulder has been temporarily continued to use, because of its low wear resistance will soon wear. In order to improve the wear resistance of the surface of the shaft shoulder, the wear-resistant electrode was used instead of the electrode for repair welding, which improved wear resistance of surface, so as to improve the service life of the shaft shoulder and extend the service life of the heavy duty apron feeder.