In this project, the causes and solutions of factors which delay the manufacturing process of I-shaped and rectangular shaped prestressed pile. The raw data was gathered using the close-ended questions and 135 employees from 3 the prestressed pile manufacturing factories were randomly selected to be interviewed. The major types of factors were specified into 4 categories which are 1.) Personnel, 2.) Tools and Equipment, 3.) Materials, 4.) Methodology. Then, the results are mathematically and statistically synthesized by evaluating the average values and standard deviations. Consequently, those results are analyzed using the fish bone method.According to the 8-Losing idea
According the synthesized results, the most relevant factor which effected to manufacturing delay is Personnel category by the average value of 3.68 and standard deviation of 0.49. The second place belongs to Tools and Equipment category with the average value of 3.58 and standard deviation of 0.50. The third place is Methodology category by the average value of 3.24 and standard deviation of 0.50. The factor which caused the least delay effect is Materials category by the average value is equal to 3.01 and the standard deviation of 0.43. The result from fish bone analysis illustrated as follows 1.) The factors from personnel category do the most essential effect with the major reason of lacking skills employees, the minor reason of accidents while working and subordinate reason of not using the safety wears. 2.) Factors from Tools and Equipment category with the major reason of insufficient numbers of manufacturing equipment, the minor reason of damaged equipment and the subordinated reason of lack of repairing equipment. 3.) Factors from Methodology category with the major reason of lack of basic training for the new employees, the minor reason of mistake from machine installation and the subordinated reason of lack of methodology document. 4) Factors from Material category with the major reason of pausing pouring concrete, the minor reason of failed slump test and the subordinate reason of excessive water mixture. All analyzed factors above are ordered according to the importance of delay effect.
According to the 8-Losing idea, sources of losing were demonstrated as losing from worthless working, losing from waiting and losing of waste products.