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Predetermined Time Systems. IENG 311 Work Methods Carter J. Kerk, PhD, PE, CSP, CPE. Predetermined Time Systems. PDTS Read Chapter 29 from Konz & Johnson, 6 th Edition. Objectives - PDTS. Describe the general concept of PDTS
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Predetermined Time Systems IENG 311 Work Methods Carter J. Kerk, PhD, PE, CSP, CPE
Predetermined Time Systems • PDTS • Read Chapter 29 from Konz & Johnson, 6th Edition
Objectives - PDTS • Describe the general concept of PDTS • Understand the difference between PDTS and other standard data systems • Understand the procedure for calculating a time standard with PDTS • Know the advantages and disadvantages of using a PDTS for setting time standards
Introduction • There are times when it is not possible or practical to set time standards using time study. • You may want to use Standard Data (Chapter 30) or Pre-Determined Time Systems (This chapter!)
Therbligs • Frank and Lillian Gilbreth took a detailed look at work and broke work into 17 micro-elements, called Therbligs • They used Therblig analysis to perform micromotion analysis of tasks (yes, they did this in the early part of the 1900s) • They used it to analyze bricklaying (a 2000 year-old task) and were able to increase productivity by 300%
G Grasp P Position PP Pre-position U Use A Assemble DA Disassemble RL Release Load TE Transport Empty TL Transport Loaded SH Search ST Select H Hold UD Unavoidable Delay AD Avoidable Delay R Rest PN Plan I Inspect Therbligs
The Concept of PDTS • Take basic, fundamental, universal units of work • Attach standard amounts of time • MTM – Methods Time Measurement • MOST (Maynard Operational Sequence Technique) • MODAPTS
MTM • MTM-1: Basic and most detailed version • 250 times the cycle time to analyze the task • Simplified Versions of MTM (less accurate) • MTM-2: 100 times the cycle time to analyze the task • MTM-3: 35 times the cycle time to analyze the task
MTM - 1 • Motions are broken into 20 categories • Reach, Move, Turn, Apply Pressure, Grasp, Position, Release, Disengage, Body Motions (leg-foot, horizontal, vertical), Eye Motions • Times for each motion is given in “TMUs” (see next slide) • Times are for experienced operators working at a normal pace (100%) • No allowances are included
MOST • Maynard Operational Sequence Technique • Developed in Sweden by Zandin • The vast majority of activities involved with the handling of an object were associated with a limited number of motion sequences • By taking advantage of this point, the time required to perform an analysis is significantly reduced from that required by MTM without a reduction in precision.
MOST • Four Sequence Models • General Move, Controlled Move, Tool Use, Manual Crane • MiniMOST • for short-cycle, highly repetitive operations • This system requires more time • MaxiMOST • For long-cycle times, with many non-identical operations
MOST • Basic MOST • General Move Sequence • Three components: Get, Put, Return • Example • GET: A1 B0 G1 • PUT: A1 B0 P3 • RETURN: A1 • See next slide for General Move Model
What is a TMU? • TMU: Time Measurement Unit • 1 hour = 100,000 TMU • 1 minute = 1667 TMU • 1 second = 27.78 TMU • 0.00001 hour • 0.0006 minutes • 0.036 seconds