Special mechanical engineering industry
From our customers’ point of view, the drilling and milling systems are at the heart of the production of special machines.
The drilling and milling systems are used to produce the various special machine parts within different platforms in a modular system according to individual customer requirements in individual or small-series production.
The drilling and milling systems are as individual as their areas of application and as diverse as the drilling and milling methods available with the corresponding tolerances. Production operates 24x7 at full order capacity.
A use time of >98% (in accordance with VDI 3423) for the drilling and milling systems is one of the most important prerequisites for assuring realistic deadlines and fulfilling the market requirements on product cycle time.
The problem:
The use time of the systems fluctuates on average between 80 and 85%. A lack of problem-solving standard processes makes it difficult to trace and rectify problems.
The challenge:
all of the departments and equipment suppliers involved (these due to the availability guarantees) must be synchronised based on their absent or deficient understanding of the categorisation of the causes of planned and unplanned plant standstills according to VDI 3423. Initial training on the standard concepts and the categorisation of plant standstills by the standard facilitates problem analysis.
Solution (Lean Kaizen, Lean DMAIC, Lean Pareto, Lean SPC, Lean Root Causes Analysis, Lean TPM, Lean A3)
In collaboration with a team from Production, Work Preparation, CIP, QA and Maintenance, possible error categories are defined for an error-recording protocol in a kaizen workshop to enable problems to be localised and quantified. Every problem corresponds to a reason for downtime in the system.
These problem categories can be recorded in a PDC, in SAP or in a log (material missing, material defect, mechanical defect, pneumatic/hydraulic defect, electrical defect, control defect, maintenance and cleaning, test/trial/simulation, geometry check, equipment not available, equipment defective, tools not available, waiting for tool pre-setting, tool storage/retrieval, tool setting, tool wear, tool breakage, machine operating error, training/qualification, production by young skilled worker, crane waiting time, deficient work documents, missing work documents, faulty NC program, lack of NC program, design enquiry, etc.).
The Results
The most common problems are localised after 3 weeks. With the help of the Lean A3 “problem-solving” tool, possible causes and possible solutions are compiled and documented in the team. This results in various PDCA projects to test the effect of the various solutions in the line organisation.
The first results were measurable after a further 6 weeks. The use time of the systems increases to 95% on average.
