Logistics, nventory, Material Flow Optimisation, Monika Uhrová, Ján Košturiak LOGSTC SYSTEM OPTMSATON Abstract n a typical factory, logistics accounts for 25% of all employees, 55% of all factory space, and 87% of production time. Logistics and material handling is estimated to resent between 15 and 70% of the total cost of a manufactured product. These figures show that there is a big potential for waste reduction in material flows and inventories. This paper describes such approach developed by PA Slovakia. 1. WASTNG N THE MATERAL FLOW Typically 95% of Total Lead Time is Non-Value Added!!! RUN TME Order Processing, Transport, Storage, Waiting, Rework, Machine Setup, nspection, Machine Breakdowns, etc... Total Lead Time Fig. 1:Where are the biggest improvement possibilities in lead time waste in material flow? The logistic system optimisation approach of PA Slovakia: 1. Analyses and process simplification logistic audit, material flow analysis, throughput time analysis, added value curve, process mapping, segmentation and manufacturing cells 2. Waste analysis flow kaizen, value stream mapping current state mapping, future state mapping 3. Bottleneck management Drum buffer rope, buffer management, SMED, batch size reduction, one piece flow, kanban 4. Dynamic simulation and optimisation of the whole logistical chain ng. Monika Uhrová, PA Slovakia, Veľký Diel 3323, 010 08 Žilina
Figure 2 Waste in material flow - examples
Ebene 0 Ebene 1 30,00 m Präsentation / Schulung Team1 Projektierung / Team 4 Lieferant / Dienstleister Konstruktion (mech./el.) Software Kunde / Besucher Kunde / Besucher Team3 Lieferant / Dienstleister 120,00m Tor1 Tor 2 Tor3 Tor 4 Tor 5 Tor6 Hauptverkehrsweg Wareneingang / Lager /Kommissionierung Galerie Team 2 Lieferant / Dienstleister Kunde / Besucher Kun de / Besuch er Team1 Lieferant / Dienstleister Präsentation / Schulung Archiv Arbeitsvorbereitung Einkauf Arbeitsvorbereitung Team 2 Projektierung / Konstruktion (mech./el.) Kunde Kunde Dienstleister QS / Normung Dienstleister Kunde Kunde Software 45,00 m Global Supra Site Location and Selection -Sites Site Planning Buildings World or Country Site Macro Building Layout Departments Building Micro Cell Layout Cells, Workstations Cells Sub- Micro Workstation Design Tool Location, Work Place Workstation Figure 3 s of logistic optimisation Figure 4 s of logistic optimisation supplier park
start: the whole work time is only 15% of the door-to-door time!!! results: optimization and value stream design shorted the door-to-door time 34% 11 Figure 5 Material flow simplification manufacturing cells 7 7 Wareneingang Ladestationen Unterbau- Lager VA Wartungsanleitung 4 stationen Glas- 54 Strahlen 11 Abdrücken 1 Dauer sonder 10 8 6 54 54 3545454 10 9 FFO FFO 8 Lade- 2 ST Supplier 6mo Forecast P/O Exception Production Control Master Schedule Mat'l Mgt Purch MRP Revised Dates Order Review Cust Service Sales Quote & estimate Order Review RFQ Quote P/O Customer Wire L/T= 10d Sheet Metal L/T= 5d Plastic L/T= 10d Machine Shop Subassy components 6 C/T = 2m Weekly Plan Dept Schedule Prod Mgr Daily Prod Meeting P/O & Job Folder Reject Report Hit Rate = Unknown Qoute L/T = 3d Order L/T = 3-5d Customer Order Shipping Ticket Current Demand = 200,000/yr = 833/day Available Time = 1 shift = 430m = 25,800s Takt Time = Avail Time/# units/day = 25,800s/833units = 31 sec C/O = 30m 8,000 pcs Batch = 500pcs 1X / Week Rel = 99% Power Press 60 days Constant Buffer 4 Machines 2 C/T = 0.5s ea C/O = 1.5h Batch=10,000pcs Yield = 90% Rel = 95% Molding Constant buffer 10 Machines Typ 4 cav mold 4 40,000 pcs 20,000 pcs Winding 3 C/T = 22s C/O = 1h Batch = 500pcs Subassembly Wind Bobbin Solder & Term Assy 4 3,300 pcs C/T = 2m C/O = n/a Batch = 50pcs Rel = n/a Subassembly Subassembly Final Assembly Testing Contact assy Motor assy Stator assy Rotor assy Bracket assy 400 6 1,700 6 12 2,250 8 pcs pcs pcs C/T = 45s C/T = 1m C/T = 25s C/T = 2.5m C/O = 15m C/O = n/a C/O = n/a C/O = n/a Batch = 50pcs Batch = 50pcs Batch = 150pcs Batch = 250pcs Rel = 100% Rel = n/a Rel = n/a Rel = n/a Ship C/T = 12s ea C/O = 3h Yield = 90% Rel = 95% Batch = 5000pcs Rel = 85% level 1 value stream & control of processes level 2 optimization & standardization of processes level 4 reducing problems in detail mini-projects level 4 enlargement to other value streams Figure 6 Process simplification using value stream mapping
2. NVENTORY REDUCTON PROGRAMME The main steps of the inventory reduction programme are: 1. ABC/XYZ analysis final products, work in process, material and components, spare parts 2. Analysis of the inventory turnover 3. Analysis of the warehouse and storage system (material position, material identification, material preparation, input/output control) 4. Material flow analysis Sankey diagram, distances, number of transportation trips, value added and non-value added activities. 5. Throughput time analysis 6. Space utilisation analysis 7. Material flow matrix construction. 8. nventory level analysis final products, WP, raw materials. 9. Value added curve construction and logistic cost analysis 10. Setup time reduction and lot size minimisation (when necessary) 11. nventory control system proposals - inventory safety levels, removing of unnecessary material items from shop floor, FFO control, visualisation, etc. 12. New inventory control model, forecasting model implementation (when possible) 13. Value stream mapping and dynamic simulation of the value flow 14. Total optimisation of the value chain % Kumulative r Anteil de s Artike ls zu de r ge samten Bestandengross e 100,0 95,0 90,0 85,0 80,0 75,0 70,0 65,0 60,0 55,0 50,0 45,0 40,0 35,0 30,0 25,0 20,0 15,0 10,0 5,0 0,0 A B C A 68 Products / 75% nventory value 53 649 870,99 = 68 Artikel, 75% Anteil A B 10 144 729 Products 974,19 / = 15 144 % nventory Artikel, 15% value Anteill B C 1749 7 153 Products 316,13 = / 1,1 1749 % Artikel, nventory 10% value Anteil C 1 10 1 20 1 30 1 401 501 601 701 80 1 90 1 1 001 1 10 1 1 20 1 Products Artikel Fig 7 ABC nventory analysis 1301 1401 1501 1601 1 70 1 1 80 1 1901
nput data collection nput information analysis Calculation of the basic indicators nventoryturnover calculation ABC analysis nventory analysis group "A" Analysis of causes for high inventories Selection of the ordering and optimisation models Measuresfor continuous inventory reduction New inventory management system 140 m 2 180 m 2 500 m 2 3120 m 2 1200 m 2 Fig 8 nventory and space reduction programme
Scrap nventories nsufficient nspection Unstable Processes Waiting for Materiall dle Times Low Discipline Unbalanced capacities Wrong purchasing Long Setup Times Figure 9 nventory reduction a way towards one piece flow
Figure 10 Dynamic simulation This article was originated with financial support of VEGA project No. 1-9222-02 and of KEGA project No. 3-0169-02.