determination and control method of horizontal displacement control parameters
determination of horizontal displacement control parameters: rotary kiln is the main equipment for clinker burning in cement plant, and its specifications are expressed by the inner diameter and length of the cylinder. The cylinder is 3 ~ 18m long and 1.8 ~ 6m in diameter, floating on 2 ~ 6 pairs of supporting wheels, and the number of supporting wheels depends on the diameter and length of the kiln, and the load of the kiln body is transferred to the foundation through the supporting wheel base. According to the different production processes, the general wet kiln has six foundations, while the precalciner kiln only needs two or three foundations, and its structural forms are generally massive concrete foundation and reinforced concrete wall foundation. In order to ensure the normal and effective operation of rotary kiln, there must be a safe and reliable foundation to support it. Rotary kiln is driven by motor through reducer and gear, and the rotating speed is very low, generally around 3r/rain. The rotary kiln body has a slope of 3% ~ 5%, the material enters from the high-end kiln tail, and the fuel is injected from the low-end kiln head, forming a convection between the material and the high-temperature flue gas. Because of the high temperature in the calcination zone in the kiln, the kiln body will be deformed, which will sometimes lead to the vacancy of a supporting wheel and uneven stress on the foundation.
in order to ensure the safe and normal operation of rotary kiln, it is necessary to control not only the bearing capacity of foundation and foundation, but also the deformation of the whole foundation. However, the parameters of deformation control are blank, and there is no clear requirement in design specifications, design manuals and even equipment manufacturing companies, especially the stiffness of the foundation itself. Designers generally refer to the conventional engineering examples first, and then the rotary kiln assumes a section, and then the strength is checked, but the deformation is often not checked, so that if the conditions of the designed foundation are similar to those of the engineering examples, there will generally be no problems, but if the design foundation is very different from the engineering examples, designers must completely re-check. For massive foundation, the stiffness is already very large, the displacement is generally very small, and deformation is not the main problem; For the wall foundation, the designer usually calculates it according to the reinforced concrete closed frame, and the deformation control parameters only refer to the requirements of the frame structure, that is, the horizontal displacement of the top surface of the foundation does not exceed 1/55 of the height of the foundation. For example, when the foundation height is 5～7 mm, the horizontal displacement of the top surface of the foundation should not exceed 9 ~ 13 mm, and when the foundation height of the rotary kiln is 175mm, the horizontal displacement of the top surface of the foundation should not exceed 32mm, which is no problem for ordinary buildings with reinforced concrete frame structure, but it is a problem that cannot be ignored for the rotary kiln foundation subjected to horizontal force for a long time.
the cylinder of the rotary kiln is floating on the supporting wheel, which is fixed on the foundation, and the reducer driving the rotary kiln is also fixed on the foundation, and the reducer and the cylinder of the rotary kiln are driven by gears. When the rotary kiln was just started, the instantaneous horizontal force acting on the rotary kiln cylinder by the reducer was very large, forcing the rotary kiln cylinder floating on the idler to move in the direction of the horizontal force. With the gradual increase of the moving amount, the horizontal force acting on the rotary kiln by the reducer gradually decreased, and the rotary kiln cylinder basically returned to its original position. At this time, the horizontal force acting on the rotary kiln by the reducer increased. Repeatedly, the horizontal force with changing size is generated on the top surface of the foundation, and the displacement with changing size also appears, thus causing the shaking of the rotary kiln foundation. When the stiffness of the foundation is large, the horizontal displacement is very small, and the shaking is basically not felt. On the contrary, this kind of shaking makes people feel uncomfortable and sometimes affects the normal operation of the equipment. Therefore, it is very important to determine a reasonable and feasible horizontal displacement control parameter according to the operating characteristics of rotary kiln. Especially in recent years, the foundation height of rotary kiln in some projects has reached 16 ~ 18m, which makes it more urgent to need this parameter. However, it is not an easy task to determine this parameter. If it is small, it will inevitably increase investment, and it is not feasible technically. If it is confirmed, it will definitely affect the safe operation of the kiln. A few years ago, we made a design return visit to dozens of completed projects. The results showed that all the projects with the calculated horizontal displacement at the top of the foundation less than 3mm operated normally, and the foundation did not shake obviously. We took 3mm as the control parameter of the horizontal displacement of the rotary kiln foundation. At present, we have designed dozens of production lines according to this parameter, and the uCClO 5t/d clinker production line in UAE is also controlled according to this parameter. Now everything is running normally.
control method of horizontal displacement: in order to control the displacement at the top of the foundation not to exceed 3mm, we must ensure that the foundation has certain rigidity. The concrete measures are: adopting massive foundation; For wall-type foundation, the wall thickness can be increased and the transverse shear wall can be directly increased, which are all very effective methods.
determination of control parameters of settlement difference of rotary kiln
the settlement difference of rotary kiln refers to the settlement difference between the foundation of rotary kiln and the kiln head and kiln tail, which directly affects the normal operation of rotary kiln. There was a safety accident that the sealing ring and smoke chamber were damaged because of the excessive settlement difference between the foundation and kiln tail. The determination of this parameter is based on our return visit to some cement manufacturers and the communication with large international cement equipment manufacturing companies. At present, we control the settlement difference of rotary kiln within 5mm in the design. Practice has proved that this design can fully meet the requirements of equipment operation.
Henan Gongyi Xinxing Machinery Factory is a joint-stock enterprise engaged in large and medium-sized series of mining machinery, mainly including dryers, ball mills, rotary kilns, coal slime dryer, crushing equipment, grinding equipment, sand making equipment, magnetic separation equipment, sand washing equipment, drying equipment, mineral processing equipment and other heavy machinery and equipment. The company is located in Kangdian Industrial Economic Development Zone, Gongyi, Henan Province. Excellent service, high quality and low price, trustworthy! Welcome people from all walks of life to visit and buy on the spot. This information is provided by www.gyxxjx.com.