【作者】 肖文忠；

【导师】 谢如鹤；

【作者基本信息】 中南大学 ， 物流工程， 2010， 博士

【摘要】 我国铁矿石产量分布严重失衡,河北、辽宁、内蒙古等3个省占全国的比例约7成,给钢铁物流行业提出了巨大的挑战,加上我国物流行业发展极其分散,竞争混乱而又激烈,从而导致我国的钢铁流通行业业态落后,没有形成大流通的体系,流通成本高,流通效率低。钢铁产量的大幅增长满足了我国快速发展的国民经济,带动了钢铁行业以及下游产业的飞速发展,但也增加了对海外铁矿石的依赖程度,其中最严重的就是进口铁矿石价格的连续性上涨,源于采购谈判中的弱势地位,近5年来铁矿石谈判结果均是以涨价告终,2008年更是接受了巴西矿涨价65%,澳矿涨价79.88%的历史最高涨幅,使我国钢铁企业遭受了巨大了损失。国内钢铁企业铁矿石协同采购水平偏低,与国外钢铁企业的差距较大,严重制约了我国钢铁企业的可持续发展。本文在分析国内钢铁企业铁矿石采购现状基础上,对典型钢铁企业协同采购流程、钢铁企业间铁矿石协同采购策略、钢铁集团铁矿石内部协同采购策略、MRPⅡ管理环境下钢铁企业采购周期优化分析等问题进行了系统研究。对钢铁集团采购协同化、一体化研究,有利于物流成本降低,市场竞争力提高。主要内容如下：(1)钢铁集团协同采购模式、流程和方法分析影响铁矿石采购的关键因素,剖析了协同采购的基本模式和内容,并以HL钢铁集团为例阐述了实现铁矿石协同采购的基本流程和方法。(2)铁矿石供应商和采购联盟间合作的最优边界条件分析以系统利润最大化为目标,综合考虑采购和生产过程中双方协调成本、生产成本,引入投入产出比率,构建了对应的的数学模型,通过比较分析,得出铁矿石供应商和采购联盟之间是否合作的最优边界条件(3)钢铁集团间铁矿石协同采购最优策略分析以供应商和采购商是否合作及采购商是否联盟采购、联盟运输为标准,以利润最大化为目标,在构建的数学模型中考虑了供需双方合作时的协调成本,采购商联盟时的协调成本等相关成本,通过比较得出：协调成本满足一定条件时,联盟采购、联盟运输是最优策略。(4)钢铁集团内部铁矿石系统采购策略优化分析基于子策略采购物流成本分析求解其最优成本,建立以需求契合度最大化和采购物流成本最小化为目标的采购策略模型,并采用平衡因子转化为单目标模型,依据对单独采购的评价选取每个子公司的供应商,采用逐步构解的邻域方式设计求解问题的模拟退火算法和遗传算法,对典型算例进行求解和比较分析。(5) MRPⅡ管理环境下钢铁集团采购周期优化分析通过归纳分析产品物料清单BOM及采购周期,建立了成品的“采购周期分布函数”,以辅助描述产品的时间成本特性,通过在某钢铁制造企业的实际应用分析,将传统MRPⅡ应用的着眼点从具体一种原材料转移到宏观的采购资金量分析上,在一定程度上简化了钢铁企业在铁矿石等主要原材料合理采购周期计算过程中的经济特性分析和运算复杂度。更多还原

【Abstract】 Distribution of iron ore in China is mainly in Hebei, Liaoning and Inner Mongolia, which occupy about 70% of the total output. Therefore, steel logistics enterprises have to face huge challenge. At the same time, logistics sector is still in developing period, disorder and furious competition lead to a lagged sector pattern. Furthermore, large-scale circulation of steel sector has a long way to come into being. Circulation cost is relatively high and circulation efficiency is low.The significant growth of steel yield meets the need resulted from rapid economic development, drives fast development of downstream industry, increases the reliability degree to the oversea iron core. The most serious problem is that the import price of iron ore has been soaring continuously. Due to the minority negotiation position, the price has not yet been hold for successive 5 years, as a result, we have to accept a price increase of 65% of Brazil iron ore and 79.88% of Australia one in 2008, this makes steel enterprises suffer huge loss.Collaborative procurement level of steel companies in China lags far behind that in some developed countries, directly restricts the sustainable development of steel industry.Based on the detailed analysis on the purchasing characteristics of iron ore in China, this paper focuses on collaborative procurement process of iron ore in typical enterprise, iron ore collaborative procurement strategy between different steel companies, coordinate purchasing tactics inside certain steel group as well as optimization method of materials purchasing cycle in the management environment of MRPⅡ. Reasearch on steel group procurement collaboration and integration is in favour of logisitics cost lower and market competition strength improved. Detailed research content is listed as follows:(1) Mode, process and method of collaborative procurement in steel groupSome critical factors affecting purchasing cost of iron core are analyzed in detail, the basic mode and content of cooperate procurement are listed, taking HL steel Group company as an example, the means in which to carry out success collaborative procurement as well as typical operating process are analyzed at the end of this part.(2) Analysis on the optimal boundary condition that whether iron ore vendor cooperates with procurement allianceUnder two conditions that cooperation and non-cooperation between iron ore vendor and procurement alliance, to maximize system profit, considering various costs such as coordination cost during purchasing process and production cost during producing process, as well as input-output ratio, this part establishes corresponding models under the upon two conditions, by detailed comparison, the optimal boundary condition that whether iron ore vendor cooperates with procurement alliance is presented in the last part of this chapter.(3) Optimal coordinated purchasing strategy for iron ore between steel companiesBased on iron ore supplier and buyer’s willingness to cooperate, conduct combined transportation, purchasing among buyers, and the goal of maximizing the profit, models are established respectively. In each model, the coordinate cost both between the iron ore supplier and buyer and in procurement alliance is taken into account. Through comparison, we conclude the alliance procurement and alliance transportation is the optimal strategy for the league when iron ore coordinate cost satisfies certain conditions.(4) Optimization on the Collaborative Procurement Strategy in Steel GroupBased on the detailed analysis of collaborative procurement strategy, related logistics cost of sub-tactics are considered, optimal cost is then computed. To maximize demand conformity degree and minimize procurement logistics cost, corresponding purchasing strategy model is established, which is transformed to single-objective model by balance index. Each sub-company’s suppliers are selected according to the evaluation on independent purchasing. The simulated annealing algorithm used to solve the problem is designed according to the neighbourhood method in which solutions are constructed step by step. Typical instance in reality is solved and analyzed in the last part of this chapter.(5) optimization and analysis on purchasing cycle in the MRPⅡof steel groupBased on the principle and shortages of traditional MRPⅡ, by analyzing the purchasing cycle, the Distribution Function of Purchasing Lead-time (DFPLT) is established to describe the characteristics of product time-cost. According to the application of DFPLT in some steel factory, the focus of traditional MRP is shifted from single material to the macro-scopical analysis of procurement fund. This helps companies to reduce inventory cost, improve fund flow, strengthen competitive capacity and simply the analysis and computation process of economic characteristics related to procurement.更多还原