Analysis of main shaft lifting capacity of IV abnormal area in Shuijingou Iron Mine

1 main well promotion overview
1.1 Main equipment configuration of main shaft lifting system IV# The main shaft wellhead elevation of the abnormal area is 1368.04m, the net diameter of the wellbore is 4.5m, and the lifting height is 505m. The lifting system adopts the 11m3 multi-rope bottom-loading bucket with the balanced hammer lifting method (wire rope tank), and the hoist is a tower configuration, which is responsible for the ore lifting task of the middle part of the underground 960m. JKM-2.8×6(III) E multi-rope friction hoist is used, the main wheel diameter is 2.8m, the maximum lifting speed is 8.21m/s, and it is equipped with ZKTD250/50 type DC motor, low speed direct linkage .

The ore above the middle of 960m enters the underground crushing station through the slippery shaft. The broken block is below 250mm, and slips into the lower mine bin. It is fed into the belt conveyor through the vibration discharge machine and transported to the measuring device matched with the bucket. Inside, it is lifted by the tower multi-rope friction wheel hoist to the surface mine bin and unloaded through the straight rail. The ore of the ground mine bin is transported by the vibrating ore concentrator to the belt conveyor to the plant.
1.2 Main shaft design lifting capacity IV# The main area of ​​the main well is loaded with ore in the underground, and the straight rail is used for unloading. The lifting design uses a five-stage speed map [2], see Figure 1.

The heavy-duty bucket began to accelerate at 11.73s with an acceleration of 0.7m/s2. After reaching the maximum lifting speed of 8.21m/s, the maximum lifting speed was 49.47s at the maximum lifting speed, and the deceleration switch in the wellbore was-0. 7m/s2 decelerates to run 11.01s, then crawls the straight rail at a constant speed of 0.5m/s, and then decelerates to stop at a deceleration of -0.5m/s2. The designed single stroke lifting time is 200.42s, and the lifting times are 17.96 times/h. According to the design specifications and related requirements, the main well runs 330d per year, with a daily running time of 19.5h and an unbalanced factor of 1.15. The main shaft design improvement capacity of the IV# anomaly area can reach 2.11 million t/a.
1.3 The actual lifting capacity of the main well At present, the main well has been commissioned and put into production operation, and the equipment configuration is consistent with the design. However, according to the feedback from the construction unit, the current actual lifting capacity of the main well is only 1.31 million t/a, which is quite different from the design capability.
2 Analysis of the reasons for the difference in the main shaft lifting capacity After investigation and analysis, it was found that the main reason for the significant reduction of the main shaft lifting capacity was that the electric control manufacturer did not debug the speed map parameters determined by the design, and the lifting speed or acceleration was smaller than the design parameters, which lengthened the lifting. Schedule time.
According to the on-site speed commissioning report of the lifting system provided by the electric control manufacturer, the actual lifting speed map and the lowering speed map of the bucket are shown in Figure 2 and Figure 3, respectively.

It can be seen from the velocity diagram that the actual acceleration of the bucket is only 0.23m/s2 when it is lifted, which is 32.9% of the design acceleration (0.7m/s2) and the deceleration is 0.5m/s2. Speed ​​(0.7m/s2)
71.4%; the acceleration at no-load down is 0.27m/s2, which is 38.6% of the design acceleration, and the deceleration is 0.49m/s2, which is 70% of the design deceleration.
The increase and decrease of the speed is greatly reduced, which leads to the extension of the running time of the acceleration and deceleration section. The effective time of the bucket running at a maximum speed of 8.21m/s is greatly shortened. One lifting cycle time is 323.43s (the heavy load is raised + empty) Loaded and lowered), the number of hours of improvement was 11.13 times. Compared with the design of 17.96 times, the iron ore was reduced by 1.43 million tons per hour, resulting in a decrease in lifting capacity.
The electric control system actually used by the main shaft hoist is based on the "external silicon expansion speed control device" modified by Siemens 6R70 DC speed control device and the automatic magnetic field constant armature controlled by Siemens S7-300PLC. Reversible series 12 pulsation DC hoist control system. The system replaces the high-power components in the original Siemens speed control device by externally installing domestic "thyristor". The overall speed of the "silicon-expanding" speed control device is given by the harmonic response time and the acceleration and deceleration performance is worse than the original device. Therefore, the actual acceleration and deceleration rate is smaller than the design [3], and the design requirements are not met.
FIG 3 is designed to enhance the speed and the maximum acceleration safe deceleration Examples of the metal and nonmetal mine safety regulations for design of mining and metallurgical mines, cage hoisting shaft using human reliability analysis does not exceed 0.75m / s2, and for skip lifting Not required [4]. In addition, the industry believes that the current maximum acceleration and deceleration rate at home and abroad should not exceed 1m / s2, within this range, the current level of electronic control technology can be achieved.

The main shaft of Lilou Iron Mine and the mixed well of Nantunhe Iron Mine are all designed by MCC Jingcheng (Qinhuangdao) Engineering Technology Co., Ltd., and its acceleration basically meets the design requirements.
3.1 Lilou Iron Mine main shaft Lilou Iron Mine ore lifting well including 1# main well, 2# main well and Wuji main well, all adopt 17m3 bottom unloading bucket with counterweight lifting method, JKM-4× 6 (III) E type tower multi-rope friction wheel hoist, the main wheel diameter is 4m, equipped with DC synchronous motor. The design acceleration is 0.7m/s2, and the electric control manufacturer is Sweden ABB. It can be seen from Fig. 4 that the speed of the hoist drum is increased from 1.50578r/min to 47.5282r/min, that is, the lifting speed of the bucket is accelerated from 0.3152m/s to 9.9492m/s, which is 14.4s. The acceleration a is 0.67 m/s2. The actual acceleration is slightly smaller than the design value, but it is basically close.

3.2 Nanxunhe Iron Mine Mixing Well The Nanxuhe Iron Mine mixed well cage lifting design acceleration and deceleration rate is 0.5m/s2, and the electric control manufacturer is Luoyang Yuanchuang Electric Company. The actual commissioning speed of the mixing well cage is shown in Figure 5.
It can be seen from the time and speed parameters identified in Figure 5 that the heavy-duty cage is timed from 10:22:01 to 10:22:15, which takes 14s, and the cage lifting speed is accelerated from 0.5m/s to 7.5m/ s, the acceleration a is
0.5m/s.
It can be seen that the conventional design of the cage lifting system can achieve the acceleration and deceleration of 0.5m/s2. The actual acceleration of the Nanfeihe iron mine is the same as the design.
4 Conclusions It can be seen from the above mine examples that the design elevation speed map of the main well in the IV# anomaly area of ​​Shujigou is safe and reliable, and the acceleration and deceleration speed is 0.7m/s2. In the provision of electronic control equipment and on-site commissioning, if the construction unit does not make other special requirements for the system, the electronic control manufacturer shall strictly follow the design requirements of the design institute for the operation of the lifting system and adjust the speed map to meet the performance of the electronic control system. Requirements and production scale requirements of the mine.
References [1] Li Laizhuang, Wang Hui, Wei Guochang, et al. Inner Mongolia Dazhong Mining Co., Ltd. Shujigou Iron Mine III, IV anomaly area expansion project design [R]. Qinhuangdao: Zhongye Jingcheng (Qinhuangdao) Engineering Technology Co., Ltd., 2015.
[2] Zhang Menglin. Mining Design Manual: Mining Machinery Volume [M]. Beijing: China Building Industry Press, 1989.
[3] Yu Limin, Yan Zilian. Mine manual equipment selection manual [M]. Beijing: Coal Industry Press, 1990.
[4] China National Standardization Committee. GB16423—2006 Safety regulations for metal non-metallic mines [S]. Beijing: China Standard Press, 2006.
Author: Xiaobo, Weiguo Chang, Jiang Shenglin; CERI (Qinhuangdao) Engineering Technology Co., Ltd;
Zhang Pan; College of Resources and Environment , Northeast Agricultural University ;
Article source: "Modern Mining"; 2016.7;
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