Operations Management Module 17 - Line Balancing PDF

Operations Management Module 17 LINE BALANCING IN OPERATIONS MANAGEMENT DR. AURA MARIE B. NOVESTERAS, PIE, ASEAN ENGR. Learning Outcomes At the end of the module, you should be able to: 1. Understand the concept of line balancing 2. Evaluate the importance of line balancing in...

Operations Management Module 17 LINE BALANCING IN OPERATIONS MANAGEMENT DR. AURA MARIE B. NOVESTERAS, PIE, ASEAN ENGR. Learning Outcomes At the end of the module, you should be able to: 1. Understand the concept of line balancing 2. Evaluate the importance of line balancing in manufacturing. 3. Determine the effect of balanced and unbalanced line in production 4. Calculate and Apply Balancing Techniques Workstation 100 ORDERS Workstation 1 Workstation 2 Workstation 3 Workstation 4 Workstation 5 INPUT OUTPUT Workstation 6 Workstation A workstation is a designated area in a workplace, specifically organized to perform a particular task. It is a physical space and functional setup designed to enhance efficiency, safety, and productivity. Features of Workstation A workstation suits the specific requirements of a task such as assembling components, performing inspections, or packaging products. Each workstation must have the tools, machinery, and materials required for the assigned tasks. Workstations are designed with ergonomics to reduce worker fatigue, improve comfort, and minimize injury risks. They are part of the overall workflow in a production or service process, contributing to seamless operations Assembly Line Assembly Line is a production process in which a product is assembled sequentially as it moves through a series of workstations. A specific task is performed at each station, gradually adding components or performing operations until the final product is completed. Unbalanced Line Must wait Must wait for Operator Constraints for Operator 3 overproduction 2 5 mins 25 mins 15 mins 10 mins Workstation 1 Workstation 2 Workstation 3 Workstation 4 Minutes  Effects of Unbalanced Line 1. A Bottleneck happens because workstations with excessive tasks slow down the entire production line. 2. Workstations with fewer tasks or faster completion rates will remain idle, wasting time and resources. 3. The overall production output decreases because the line cannot operate at optimal efficiency. 4. Overburdened workers at bottleneck stations may experience stress and fatigue. 5. A disrupted workflow can result in failure to meet production deadlines, impacting customer satisfaction. Balanced Line Reduces Avoids Minimizes Variation Promotes one Overburden Wastes piece flow 15 mins 15 mins 15 mins 10 mins Workstation 1 Workstation 2 Workstation 3 Workstation 4 Minutes Line Balancing Line Balancing in manufacturing levels the workload across all processes in a cell or value stream to remove bottlenecks and excess capacity. Line Balancing is the process of assigning tasks to workstations in such a way that workstations have approximately equal requirements. Concept of Line Balancing 1. Bottleneck The workstation taking the longest time. A delay in the transmission slows down the production rate. This can be overcome by balancing the line. A bottleneck (or constraint) in a supply chain is the resource that requires the longest time in operations of the supply chain for a certain demand. Concept of Line Balancing 2. Required Cycle Time or Takt Time The maximum amount of time allowed at each station. This can be found by dividing required units by the production time available per day. This is the time expressed in minutes between two simultaneous products coming from the end of the production line. 𝑂𝑝𝑒𝑟𝑎𝑡𝑖𝑛𝑔 𝑇𝑖𝑚𝑒 𝐴𝑣𝑎𝑖𝑙𝑎𝑏𝑙𝑒 𝑅𝑒𝑞𝑢𝑖𝑟𝑒𝑑 𝐶𝑦𝑐𝑙𝑒 𝑇𝑖𝑚𝑒 = 𝑅𝑒𝑞𝑢𝑖𝑟𝑒𝑑 𝑂𝑢𝑡𝑝𝑢𝑡 Concept of Line Balancing 3. Lead Time The latency between the initiation and completion of process 4. Task Precedence The product cannot be moved to the next station if it doesn’t complete at the previous station. Network showing order of task and restrictions on their performance Concept of Line Balancing 5. Idle time A period when the system is not in used but is available. 6. Productivity Defined as the ratio of output over input. Productivity depends on several factors such as workers’ skills, jobs method, and machine used. Steps in Solving 1. Draw the precedence diagram of each workstation a b c e d Steps in Solving 2. Identify the bottleneck or cycle time minimum which is the longest task time 3. Compute the output capacity 𝐴𝑃𝑇 𝑂𝐶 = 𝐶𝑇𝑚𝑖𝑛 𝑂𝐶 = output capacity 𝐴𝑃𝑇 = Available production time 𝐶𝑇𝑚𝑖𝑛 = Cycle Time minimum Steps in Solving 4. Calculate the efficiency of the existing product σ 𝑡𝑎𝑠𝑘 𝑡𝑖𝑚𝑒 𝑒𝑓𝑓𝑖𝑐𝑖𝑒𝑛𝑐𝑦 = 𝑥 100 𝐶𝑇𝑚𝑖𝑛 𝑊𝑆𝐴 5. Calculate the CT new based from the daily demand 𝐴𝑃𝑇 𝐶𝑇𝑛𝑒𝑤 = 𝑂𝐶𝑛𝑒𝑤 Note: the sum of the task time of WS should be equal or near to CT new. Steps in Solving 6. Calculate the minimum number of Workstation and assign the task σ 𝑡𝑎𝑠𝑘 𝑡𝑖𝑚𝑒 𝑊𝑆𝑚𝑖𝑛 = 𝐶𝑇𝑛𝑒𝑤 7. Draw the updated precedence diagram 8. Evaluate the efficiency Example What should be the minimum number of workstation if production time is 8 hours. They have a break of two 15 minutes. The new market demand is 260 units per day. Tasks are written below. Perform a line balancing. 1. Draw the precedence diagram of each workstation 2. Identify the bottleneck or cycle time minimum which is the longest task time 3. Compute the output capacity 4. Calculate the efficiency of 𝐴𝑃𝑇 the existing product 𝑂𝐶 = 𝐶𝑇𝑚𝑖𝑛 σ 𝑡𝑎𝑠𝑘 𝑡𝑖𝑚𝑒 𝑒𝑓𝑓𝑖𝑐𝑖𝑒𝑛𝑐𝑦 = 𝑥 100 𝐶𝑇𝑚𝑖𝑛 𝑊𝑆𝐴 5. Calculate the new CT based on the 6. Calculate the minimum number of daily demand Workstation and assign the task 𝐴𝑃𝑇 σ 𝑡𝑎𝑠𝑘 𝑡𝑖𝑚𝑒 𝐶𝑇𝑛𝑒𝑤 = 𝑊𝑆𝑚𝑖𝑛 = 𝑂𝐶𝑛𝑒𝑤 𝐶𝑇𝑛𝑒𝑤 Note: the sum of the task time of WS should be equal or near to CT new. Task Task time WS Task time label (seconds) (seconds) σ 𝑡𝑎𝑠𝑘 𝑡𝑖𝑚𝑒 a 40 𝑒𝑓𝑓 = 𝑥 100 𝐶𝑇𝑚𝑖𝑛 𝑊𝑆𝐴 b 59 c 84 d 56 e 34 f 45 ∑ Review Takt Time A company produces quality products such as product A and product B. Downtime in making product A is 60 minutes and 70 minutes in product B. Assume that line efficiency for product A is 95% and 90% for product B. They need to produce 1,500 pieces of product A per shift and 1,700 pieces of product B per shift. Consider the plant has two 8- hour shifts per day. Compute the following and show your solutions. 1. Compute the available production Time of product A in minutes per day 2. Compute the takt time of product A in minutes per piece 3. if the machine’s standard time in making product A is 300 seconds/pc, how many machines do they need to produce product A 4. Compute the available production Time of product B in minutes per day 5. Compute the takt time of product B in minutes/piece 6. If the machine’s standard time in making product B is 180 seconds per piece, how many machines do they need to produce product B? Board Work Line Balancing 1. Perform a level production for the following task. The new demand is 40 units per day, with 8 hours production period. Assume there is a two 15-minute downtime. Do the step-by-step procedure. Tasks are given below. Task Performance Time (mins) Precedence A 10 - B 11 A C 5 B D 4 B E 12 A F 3 C, D G 7 F H 11 E I 3 G, H Board Work Line Balancing 5. Calculate the CT new based on the new 1. Draw the precedence diagram of demand each workstation 𝐴𝑃𝑇 𝐶𝑇𝑛𝑒𝑤 = 𝑂𝐶𝑛𝑒𝑤 2. Identify the bottleneck or cycle time minimum which is the longest task time 6. Calculate the minimum number of Workstation and assign the task 3. Compute the output capacity 𝐴𝑃𝑇 𝑂𝐶 = σ 𝑡𝑎𝑠𝑘 𝑡𝑖𝑚𝑒 𝐶𝑇𝑚𝑖𝑛 𝑊𝑆𝑚𝑖𝑛 = 𝐶𝑇𝑛𝑒𝑤 4. Calculate the efficiency of the 7. Draw the updated precedence diagram existing workstation σ 𝑡𝑎𝑠𝑘 𝑡𝑖𝑚𝑒 𝑒𝑓𝑓𝑖𝑐𝑖𝑒𝑛𝑐𝑦 = 𝑥 100 8. Evaluate the efficiency 𝐶𝑇𝑚𝑖𝑛 𝑊𝑆𝐴 Board work Line Balancing 2. Below are the task elements of making pizza. Working time is from 6 am to 2 pm with 40 minutes downtime. The new demand is 60 units per hour. Element Task Description Performance time (sec) Precedence A Roll Dough 50 - B Place on Cardboard backing 5 A C Sprinkle cheese 25 B D Spread sauce 15 C E Add pepperoni 12 D F Add sausage 10 D G Add mushroom 15 D H Shrink rap size 18 E,F,G I Place in a box 15 H Homework Line Balancing