Last week's (week 11) completed MRP table for the 36" RH doors is shown below. Assuming we are now at the start of week 12, you are to develop the updated MRP plan for weeks 12-19. We actually have 7 of these doors in stock (vs. the value 10 that was projected in the tables computed back in week 11), with updated demand information as provided in the spreadsheet linked below. YOU need to enter any Scheduled Receipt information that belongs in the week 12-19 MRP table for 36" RH doors, based on what you see below in the week 11-18 MRP table. Notice the table below shows 142 of the 36" RH Pre-Hung Doors that should be ordered in week 11 (because the planned release is in week 11), to be received in week 12 (because the planned receipt is in week 12). Assuming we actually ordered those 142 doors in week 11 like we were supposed to, in week 12 they would be showing up as a scheduled receipt in week 12, rather than as a planned receipt in week 12.

As explained in the commentary, scheduled receipts are telling us when we will receive units that have already been ordered. The planned release row tells us when we should be ordering units that have not been ordered yet. (The planned receipt row shows us when we plan to be receiving orders that have not been ordered yet.) These "planned" quantities could still change when the MRP tables are recomputed using new information. Once an order is actually placed, (released for production or released to the supplier), the order quantity (now a scheduled receipt) typically does not change.

Assignment 1 Figure 2.

This figure shows the completed MRP table for items 36" RH Pre-Hung Door, using a planning horizon of weeks 11 to 18.

Similarly, the weeks 11-18 MRP table for the 36"LH pre-hung door is shown below. Given this information, fill out the week 12-19 MRP table for this item, using the updated demand and inventory information provided in the spreadsheet linked below. You will need to update the Scheduled Receipt row for the 36"LH Pre-Hung door, based on what you see in the planned release and planned receipt for the week 11-18 MRP table shown below. (In the next lesson you will work with a real-life MRP system and see how this is implemented in practice.)

Assignment 1 Figure 3. This figure shows the completed MRP table for items 36" LH Pre-Hung Door, using a planning horizon of weeks 11 to 18.

Notice we are also producing the 32" and 36" versions in alternate weeks, and plan to stick to that schedule. (Notice all the scheduled and/or planned receipts for 32" doors are in odd-numbered weeks, while all the 36" versions have scheduled and/or planned receipts in even numbered weeks.) If a small net requirement to replenish safety stock appears to be prompting a planned receipt in an "off" week for the item in question, the net requirement will simply accumulate until the next "normal cycle" planned receipt period for that item. Your scheduled and planned receipts should stick to the "every other week" pattern established for each item, using the POQ = 2 weeks lot sizing rule. We will not expedite an order for the purpose of maintaining safety stock. To the contrary, we will remember that the purpose of safety stock is to help "stabilize" the production schedules and reduce the need for expediting.

Use the blank tables provided in the Excel workbook below for both problems. Be sure to enter your name in the indicated cell before you submit your solution.

Item: 36" RH Pre-Hung Door On Hand: Safety Stock: LT = 1 week Lotsize: POQ = 2 weeks 10 11 | 70 12 65 13 77 14 82 15 70 16 70 17 70 18 70 week: Gross Requirements Scheduled Receipts Projected On Hand (EI) Net Requirement Planned Receipt Planned Release 10 0 87 65 142 0 10 0 0 152 80 1080 10 820 70 0 152 0 1400 0 1400 70 10 70 70 142 Item: 36" LH Pre-Hung Door 83 10 11 67 12 73 13 70 LT = 1 week Lotsize: POQ = 2 weeks 14 15 16 17 18 65 65 65 65 65 On Hand: Safety Stock: week: Gross Requirements Scheduled Receipts Projected On Hand (EN) Net Requirement Planned Receipt Planned Release 16 80 10 75 1075 10 10 067 065 065 065 137 01300 130 0 65 137 0 1300 1300 65 B C D E F G H I J Planned Release Item: 36" RH Pre-Hung Door (you need to add any scheduled receipts) LT = 1 week Lotsize: POQ = 2 weeks 10 12 65 13 77 14 82 15 73 16 70 17 70 18 70 19 70 37 Gr 33 On Hand: 34 Safety Stock: 35 36 week: Gross Requirements 38 Scheduled Receipts 39 Projected On Hand (EI) 40 Net Requirement 41 Planned Receipt Planned Release 45 Item: 36" LH Pre-Hung Door (you need to add any scheduled receipts) 20 On Hand: 48 Safety Stock: 70 LT = 1 week Lotsize: POQ = 2 weeks Lotsieet = 1 week 10 12 | 73 13 70 14 65 15 65 16 65 17 65 18 65 19 65 50 Week: 51 Gross Requirements 52 Scheduled Receipts 53 Projected On Hand (EI) 54 Net Requirement 55 Planned Receipt 56 Planned Release