Construction Schedule Control Of Heating Furnace Based On Critical Chain Technology

Construction schedule control is an important component of project management.The traditional technology of construction schedule control includes Gantt chart,Critical Path Method and Program Evaluation&Review Techniques.Although they have own advantages in schedule management,there are many changes in the schedule because of the uncertainty in the process of the project.In this paper,construction constraints of heating furnace are analysed with the theory of Constraints,and it is considered that the process constraints mainly come from human resources,machinery and raw material resources.No matter what kind of resources is conflicting,that means the total quantity of resource that needed by a process is more than the resource of the largest supply,the imbalance will make up constraints and delay the construction schedule of the process.And this paper studies the methods of the maximum delay-time method and critical chain confirming and butter setting based on Critical Chain Technology.With time separating,processes differentiating,MAXD calculating and ranking,comparing,analyzing,the method of MAXD is used to determine whether a resource of the process to be a constraint resource.According to CCPM,we draw project network in line with process of logical constraints,and then adjust the project network by the process of resource constraints(such as labor,equipment,etc.)reasonably.So we have an initial schedule,and the longest line is the project critical chain.Then,the duration of all project processes is reduced by half,and the saved time will be entered the project network as the buffer.There are three main types of buffer:Project Buffer,Feeding Buffer and Resource Buffer.To control the project schedule with the management of buffer is the characteristic of CCPM.With all above analysis,Goldratt 50%completion probability is sured to be suitable for duration estimating of heating furnace project,and the 50%method is fit for buffer size setting of heating furnace project.This article also offers a method of PB respectively inserted to solve the problem of no necessary of critical chain adjustment,and the corresponding mathematical model is established.As a case,reformation of heating furnace of Bar Steel Rolling of SG company was practiced.On the basis of the theory of critical chain and relevant material collected during my personal experience in the project implementation,the project schedule was controlled effectively and good results were achieved.And it also proved the validity correctness of resource allocation,critical chain determining,buffer setting based on CCPM,achieved the goal of the project schedule management stratagem of heating furnace in steel rolling system of metallurgical industry with excavating the constraints of the system and researching the method of buffer setting.