Scheduling Production and Process Operations

Objectives of a Schedule

·         Establish due dates

·         Determine flow times

·         Keep shop floor running smoothly

 

Scheduling Guidelines

·         Business Priorities

·         Targets

·         Rules

·         Procedures

 

Backward Scheduling

·         When must this be started to finish by…?

·         If I start now, when can I have it?

 

Dependent-Demand Scheduling

·         Mixed-Model scheduling

o   Making difference components in varying lot sizes

o   Loop … you go through your loop sequence making the different products that are triggered that go around, based on demand

·         Rate-Based scheduling

o   Based on a time period… monthly, daily, weekly, etc…

·         Synchronous Control

o   Used in pull systems

o   Drumbeat pace

o   Constant quantity on every shift

o   No less/no more

o   Slack time to ensure that rate is achieved

 

Operations Scheduling

·         Considers

o   Setup and run times at each step

o   Move times between work centers

o   Wait/queue times

·         Operation Scheduling Steps

1.       Obtain data for product to be produced

2.       Choose scheduling method

3.       Load facility

4.       Schedule

5.       Release work to shop/execute schedule

6.       Provide feedback to initial load/schedule

 

Critical Path Method (CPM)

·         The longest path, in time, through the process

 

Project Evaluation and Review Technique (PERT)

·         Assigns three estimates of time to each activity:  pessimistic, most likely, and optimistic

·         Gives managers options and varied scenarios

 

Priority Rules

·         clip_image004

o   = 1: everything is on schedule

o   Greater than 1:  ahead of schedule

o   Less than 1:  behind schedule

 

Disruptive Priorities

·         Squeaky Wheels:  the order with the loudest customer service rep

·         Gravy Jobs:  easiest or more incentivized job gets done first

·         Informal hot lists:  if everything is top priority, nothing is top priority

·         Red Tags, Green Tags, and Rush Stickers

 

Bottleneck Management

·         Steps

1.       Identify

2.       Keep it working

3.       Only feed process what bottleneck can handle

4.       Accelerate/improve bottleneck

5.       Repeat to find new bottleneck

One Comment (+add yours?)

  1. Richardson
    Sep 10, 2013 @ 21:01:36

    What about quantify questions for utilization and efficiency? Do you have text or examples?

    Reply

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