The deburring process for compressor housing no. 434.807
was chosen because Pareto diagram showed that the part number
have the biggest volume of production, which was 40 % while the
first following, has 15 %.
The first undertaken team task was to completion of a
thought process map (TMAP), Figure 3 [8]. Team approach and
idea how to solve the problem was elaborated through the TMAP.
The chosen deburring processes for compressor housing
involves following production steps:
� Sawing residual of feeding system,
� Drilling,
� Burrs removal – cleaning bases for clamping on machining area,
� Rough grinding – burrs removal in the dividing plain, and
� Control – material defects and simulation of machining
clamping system.
Process map was drawn for all operations in the deburring
process, and a list of the input and output variables were
completed. The input variables were ranked as, Critical, Noise,Controllable and Standard operating procedures variable and,
furthermore, non-value added operations are defined and marked.
Team decision was that all variables should be analyzed using
a cause and effect matrix to identify the key critical input
variables for further study. The product diameter and tube length
non-conformance, deformation of parts, quality of surface as well
as scrap are evaluated using cause and effect matrix. Each team
member filled in a questionnaire scoring influence of input
variables on non-conformance and defects. Team decided that the
main variables for further analyzing are Grossly burr, Material
and Operator from Press operation, Control operation and, Sawing
and Drilling operation.
Moreover, during period from nine months actual data for
observed process were collected and ppm and RTY indices are
calculated.
As Pareto diagram showed the highest volume of material
scrap was in the Press operation because 60 % of scrap was in the
direct relationship with removal burr on the press. Also, based on
Pareto diagram of material scrap, conclusion was that the Material
in the Sawing and Drilling operation has minor impact on the
expenses level. So, at the end of this phase, decision was that
Press and Control operations should be main objectives of further
improvements