看板管理与制订主生产计划

看板管理与制订主生产计划 看板管理不参与制订主生产计划，自然也就不参与生成能力需求计划。实现看板管理的企业通过工序、设备布置、人员培训等手段来实现生产过程的均衡化，从而大大减少了生产过程中的能力需求不平衡的现象。看板管理可以很快地暴露出能力过剩或不足的工序或设备，然后通过不断地改进来消除问题 使用MRP系统的企业在制品管理一直是一个难点，一般来说在制品数量难以控制，系统中的数据与实际情况也很难保持一致。造成这一现象的间接原因是因为MRP系统是一个“推”式生产，前道工序的生产是按照系统计算出的后道工序需求来确定的，而不是由实际生产过程中后道工序的需求来确定的，所以必然会出现生产线在制品管理的困难。直接原因是因为生产中各工序之间不合拍。实现准时化生产方式的企业在制品数量被控制在看板数量之内，关键在于确定一个合理有效的看板数量。 有些企业忽略了看板管理的技术支撑体系，从而导致了实践中的失败。根据日本丰田汽车公司的经验，单纯地采用看板管理不可能全面实现生产过程的合理化，应该首先从生产过程的合理化入手，不断改进作业方法，完善生产条件，然后逐步过渡到看板管理。由此可以看出是否具备技术支撑体系是实现看板管理的关键所在。 edges should be cleaned, after making sure that no defect shall be marked with a marker pen to write down welding near the weld, including the slogan of welding, welders, etc. (16) welding Qian Preheat and the welding Hou heat treatment pipe welding Qian Preheat and the welding Hou heat treatment process conditions welding Qian Preheat and the welding Hou heat treatment temperature table project material welding Qian preheat temperature (?) welding Hou heat treatment and the insulation time (?/H) wall thick (mm) temperature (?) wall thick (mm) temperature (?) 20 ? 26 100~200 >36 600~650/1-1.5 15CrMo ? 10 150~200 >10 670~700/1.2-2 Preheat and the heat treatment process in the, Inner and outer wall temperature shall be kept uniform, in order to avoid internal stresses. Preheating before welding and post weld heat treatment, shall measure and record the temperature, temperature measurement locations and number of points are reasonable. Prone to weld delayed crack of steel, post weld heat treatment after welding should be carried out promptly, when not conducting timely post weld heat treatment, should be uniformly heated to 200~300? immediately after welding and insulation and slow cooling, ... 26mm more than 20 steel pipe welding preheating before welding should be carried out, 36mm the above heat treatment after welding should be done. Before welding and heat treatment used oxyacetylene flame heating, heat treatment after welding using special heat treatment after welding equipment. Hardness after heat treatment of welds needed testing. 6.5.4 sides of the dissimilar steel welding when were non-austenitic steel or austenitic steel, alloy content according to lower one side of the base metal or selecting welding material in between. When one of the sides of material when austenitic steels, should select the MRP与看板管理对比: MRP 看板管理 主生产计划 系统提供 依靠现成计划 物料需求计划 系统提供 不需要 能力需求计划 系统提供 不需要 仓库管理 好 通常外包给供应商 在制品管理 差 好 技术支撑 无特别 需要完善的技术支撑 人员素质要求 普通 高 实施难度 较看板管理容易 难 适用行业 范围广 范围窄 MRP与看板管理的结合 MRP 和看板管理各有所长，又各有所短。过去企业只能在两者之中选择一种作为企业的生产管理模式，不可避免地会遇到各自的缺陷。由此可以相到:是否有途径将二者结合起来，充分发挥各自的长处，避免各自的短处，以下介绍一种结合MRP和看板管理的模式:MRP制订维护主生产计划和物料需求计划，生产过程采用看板管理。 1、MRP 系统制订维护主生产计划 edges should be cleaned, after making sure that no defect shall be marked with a marker pen to write down welding near the weld, including the slogan of welding, welders, etc. (16) welding Qian Preheat and the welding Hou heat treatment pipe welding Qian Preheat and the welding Hou heat treatment process conditions welding Qian Preheat and the welding Hou heat treatment temperature table project material welding Qian preheat temperature (?) welding Hou heat treatment and the insulation time (?/H) wall thick (mm) temperature (?) wall thick (mm) temperature (?) 20 ? 26 100~200 >36 600~650/1-1.5 15CrMo ? 10 150~200 >10 670~700/1.2-2 Preheat and the heat treatment process in the, Inner and outer wall temperature shall be kept uniform, in order to avoid internal stresses. Preheating before welding and post weld heat treatment, shall measure and record the temperature, temperature measurement locations and number of points are reasonable. Prone to weld delayed crack of steel, post weld heat treatment after welding should be carried out promptly, when not conducting timely post weld heat treatment, should be uniformly heated to 200~300? immediately after welding and insulation and slow cooling, ... 26mm more than 20 steel pipe welding preheating before welding should be carried out, 36mm the above heat treatment after welding should be done. Before welding and heat treatment used oxyacetylene flame heating, heat treatment after welding using special heat treatment after welding equipment. Hardness after heat treatment of welds needed testing. 6.5.4 sides of the dissimilar steel welding when were non-austenitic steel or austenitic steel, alloy content according to lower one side of the base metal or selecting welding material in between. When one of the sides of material when austenitic steels, should select the 当前的市场环境下，企业面对不同客户的众多需求和自身的经营规划，需要一个能迅速制订、适应各方面要求、真正可行的主生产计划。仅仅依靠手工作业的方式进行是很难达到要求的，因此企业需要借助计算机系统来帮助制订主生产计划。现阶段能够做到这一点的只有MRP系统。 2、MRP 系统计算物料需求计划 传统的MRP 系统根据主生产计划计算得出的物料需求计划不仅仅包括原的需求，还包括半成品的需求。但是我们知道MRP 系统计算出的半成品需求与生产现场的实际情况并不一定一致，这是造成在制品管理困难的重要原因。所以需要使MRP 不进行半成品需求的计算，直接将成品的主生产计划分解为原材料的采购需求。 为了做到不进行半成品需求计算，需要在物料清单中引入虚项的概念。虚项是用来标识通常不入库或一组不可能装配在一起的零件。MRP 系统不会对虚项进行需求计算，而是直接对组成虚项的原材料进行需求计算。作为虚项的半成品的生产需求将由看板来决定。 MRP 系统根据产成品的主生产计划，按照物料清单进行需求分解，计算出原材料在不同计划时区内的毛需求，然后再根据现有库存和订单情况确定最终的净需求，即原材料采购计划。即使MRP 系统产生的原材料净需求与实际生产过程的看板需求数量有差异，差异也不会很大，一般不可能出现缺料或积压的情况。这说明了MRP 系统制订的原材料需求计划是反映了物料的实际需求情况的。如果单纯使用看板管理来确定原材料需edges should be cleaned, after making sure that no defect shall be marked with a marker pen to write down welding near the weld, including the slogan of welding, welders, etc. (16) welding Qian Preheat and the welding Hou heat treatment pipe welding Qian Preheat and the welding Hou heat treatment process conditions welding Qian Preheat and the welding Hou heat treatment temperature table project material welding Qian preheat temperature (?) welding Hou heat treatment and the insulation time (?/H) wall thick (mm) temperature (?) wall thick (mm) temperature (?) 20 ? 26 100~200 >36 600~650/1-1.5 15CrMo ? 10 150~200 >10 670~700/1.2-2 Preheat and the heat treatment process in the, Inner and outer wall temperature shall be kept uniform, in order to avoid internal stresses. Preheating before welding and post weld heat treatment, shall measure and record the temperature, temperature measurement locations and number of points are reasonable. Prone to weld delayed crack of steel, post weld heat treatment after welding should be carried out promptly, when not conducting timely post weld heat treatment, should be uniformly heated to 200~300? immediately after welding and insulation and slow cooling, ... 26mm more than 20 steel pipe welding preheating before welding should be carried out, 36mm the above heat treatment after welding should be done. Before welding and heat treatment used oxyacetylene flame heating, heat treatment after welding using special heat treatment after welding equipment. Hardness after heat treatment of welds needed testing. 6.5.4 sides of the dissimilar steel welding when were non-austenitic steel or austenitic steel, alloy content according to lower one side of the base metal or selecting welding material in between. When one of the sides of material when austenitic steels, should select the 求，那么只有在主生产计划开始实行时而不是制订时才知道原材料的需求信息。在我国目前的市场条件和交通条件下，是很难作出及时的反应的。 3、生产现场采用看板管理 生产现场的各工序生产活动的节拍是否合拍是生产控制的关键。如果采用MRP 系统来管理，就会出现由MRP 系统对各工序分别下达生产指令，各工序按照其指令各自开工生产。前道工序按照系统计算出的后道工序的需求进行生产活动，不一定与后道工序的实际需求相吻合。这是因为，MRP 的计划时区通常是以周或天为单位的，而实际上许多企业尤其是流水线生产方式的企业，各工序的加工时间是以分钟甚至秒作单位。系统的时间单位与实际的不一致，就容易造成系统的需求与实际需求之间的时间差，从而容易造成生产现场的在制品积压和生产活动的混乱。采用看板管理就可以避免这种情况的发生。看板在生产过程中的各工序之间周转，将与取料和生产的时间、数量、品种等相关信息从生产过程的下游传递到上游，并将相对独立的工序个体结合为一个有机的 整体。 edges should be cleaned, after making sure that no defect shall be marked with a marker pen to write down welding near the weld, including the slogan of welding, welders, etc. (16) welding Qian Preheat and the welding Hou heat treatment pipe welding Qian Preheat and the welding Hou heat treatment process conditions welding Qian Preheat and the welding Hou heat treatment temperature table project material welding Qian preheat temperature (?) welding Hou heat treatment and the insulation time (?/H) wall thick (mm) temperature (?) wall thick (mm) temperature (?) 20 ? 26 100~200 >36 600~650/1-1.5 15CrMo ? 10 150~200 >10 670~700/1.2-2 Preheat and the heat treatment process in the, Inner and outer wall temperature shall be kept uniform, in order to avoid internal stresses. Preheating before welding and post weld heat treatment, shall measure and record the temperature, temperature measurement locations and number of points are reasonable. Prone to weld delayed crack of steel, post weld heat treatment after welding should be carried out promptly, when not conducting timely post weld heat treatment, should be uniformly heated to 200~300? immediately after welding and insulation and slow cooling, ... 26mm more than 20 steel pipe welding preheating before welding should be carried out, 36mm the above heat treatment after welding should be done. Before welding and heat treatment used oxyacetylene flame heating, heat treatment after welding using special heat treatment after welding equipment. Hardness after heat treatment of welds needed testing. 6.5.4 sides of the dissimilar steel welding when were non-austenitic steel or austenitic steel, alloy content according to lower one side of the base metal or selecting welding material in between. When one of the sides of material when austenitic steels, should select the edges should be cleaned, after making sure that no defect shall be marked with a marker pen to write down welding near the weld, including the slogan of welding, welders, etc. (16) welding Qian Preheat and the welding Hou heat treatment pipe welding Qian Preheat and the welding Hou heat treatment process conditions welding Qian Preheat and the welding Hou heat treatment temperature table project material welding Qian preheat temperature (?) welding Hou heat treatment and the insulation time (?/H) wall thick (mm) temperature (?) wall thick (mm) temperature (?) 20 ? 26 100~200 >36 600~650/1-1.5 15CrMo ? 10 150~200 >10 670~700/1.2-2 Preheat and the heat treatment process in the, Inner and outer wall temperature shall be kept uniform, in order to avoid internal stresses. Preheating before welding and post weld heat treatment, shall measure and record the temperature, temperature measurement locations and number of points are reasonable. Prone to weld delayed crack of steel, post weld heat treatment after welding should be carried out promptly, when not conducting timely post weld heat treatment, should be uniformly heated to 200~300? immediately after welding and insulation and slow cooling, ... 26mm more than 20 steel pipe welding preheating before welding should be carried out, 36mm the above heat treatment after welding should be done. Before welding and heat treatment used oxyacetylene flame heating, heat treatment after welding using special heat treatment after welding equipment. Hardness after heat treatment of welds needed testing. 6.5.4 sides of the dissimilar steel welding when were non-austenitic steel or austenitic steel, alloy content according to lower one side of the base metal or selecting welding material in between. When one of the sides of material when austenitic steels, should select the