5.04 - U-Shaped "Piece at time" Cell

Typical U-Shaped Cell

Nine processes operated by two workers. Unload a workstation, reload it with another piece, start the process and take the unloaded work piece to the next workstation

Features

• Nagare (Worker taking piece to next process, leaving previous process running) (see guide 5.11)
  • Parallel activities
  • No functional boundaries (e.g. press shop, machine shop, etc.)
  • Shortens supply line
• Standard working
  • Visual control
  • Workers know what to do at each process
  • Reduces waste
• Balanced Labour Distribution
  • Reduce waste
• Multi-skill labour
  • Flexibility
• Small Machines
  • Cheap (many copies)
  • Workers can operate more than one, easily
  • Quick and easy to maintain
• Multi-Process
  • Elimination of inter-process stock
  • Typically 50-100% productivity improvement

Benefits

• Flexibility - able to respond quickly
• Short lead times
• Minimum levels of stock
• High productivity

Traditional Batch Working - A Transfer Batch of 5

Time	5 Minutes	10 Minutes	15 Minutes	20 Minutes
1st Process
2nd Process
3rd Process
4th Process

With traditional batch working, where there are 5 items that require 4 production processes, and each operation requires 1 minute, the first item will be produced in 16 minutes and 20 minutes are required to complete the entire process.

Piece at a Time Cell

Time			1min	2min	3min	4mn	5min	6min	7min	8min
1st Process
2nd Process
3rd Process
4th Process

With piece at a time working, where there are 5 items which require 4 production processes, and each process requires 1 minute, the first item will now be produced in 4 minutes and 8 minutes are required to complete the entire process.