טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
M.Sc Thesis
M.Sc StudentKhorshid Iman
SubjectA Comparison between Squeglia's "0 Defects" and of ISO
2859-1 Incoming Inspection Sampling Plans
DepartmentDepartment of Quality Assurance and Reliability
Supervisor Dr. Avner Halevy


Abstract

Many companies are striving for “Zero Defects” through statistical process control, improved processes, control systems and other methods.
Military industries agreed to use C=0 plans experimentally.  Results of the experimental period were excellent. a survey was carried out among users in order to obtain a general picture and an idea of the level of cost savings achieved as a result of use of C=0; the majority reported savings of 18% in inspection’s costs.
In this paper I have examined the sampling plans in use in Habonim industrial valves LTD. factory which are based on “ZERO DEFECT” sampling plans developed by Squeglia, and compared it with inspection results according to the standard ISO 2859-1, in use by suppliers.
Alas investigating the meaning of a moving to incoming inspection according to ISO 2859-1, from the viewpoint of efficiency and cost. The main criterion is economic (cost against minimizing damage).and tried to recommend additional options for sampling plans.
The accumulated time invested in checking to C=0 is smaller by far than with other methods, a fact that causes many producers to be enticed into using sampling methods with the single aim of minimizing inspection times, without a deep investigation of the matter.
The cost of this work is not definable, thus it is advisable to perform a simulation of the cost entailed based on theoretical batches, since actual inspection is not practicable in the company.  This will include variation in a number of parameters, such as: batch size, C, n, item value, cost of sorting, cost of inspection. A simulation should be performed based on a large number of runs. By means of the simulation we may be able to estimate what are the actual risks of the sampling program.