Purpose: The purpose of this paper is to find the proper statistical distribution function, which can cover the failure time of a single machine or a group of machines. To this end, an innovative program is written in an Excel software, capable of assessing at least six statistical distribution functions. This research study intends to show the advantages of applying statistical distribution functions in an integrated model format to create or increase productive reliability machines. Productive reliability is a simultaneous combination of efficiency and effectiveness in reliability. Design/methodology/approach: The method of theoretical research methodology comprises data collection tools, reference books and articles in addition to exploiting written reports of the Iranian Center for Defence’s Standards. The practical research method includes deploying and assessing the proposed model for a selected machine (in this case a computerized numerical control machine). Findings: A comprehensive program in an Excel software having the capability of assessing at least six statistical distribution functions was developed to find the most efficient option for covering the failure times of each machine in the shortest time with the highest precision. This is regarded as the most important achievement of the present study. Furthermore, the advantages of applying the developed model are discussed and a large group of which have direct influences on the productivity of equipment reliability. Originality/value: The originality of the research was ascertained by managers and experts working in maintenance issues at the different levels of the Defense Industries Organization.

Purpose: of this paper consists of identifying and prioritising control tests of a product design with integrating QFD and VE techniques according to use of the lean approach to increase the productivity of product design. Design/methodology/approach: of this research is the application of four quality houses at QFD (four matrices) and VE matrix and assessment table of lean approach in the form of a combinational process. Findings: of this research were the implementation of mentioned methodology for numerical application. Bullet-head drill (27.8 inch HSD) that was applied in oil and gas industries with 5.69 scores is more than moderate in related to lean of control tests, and it is 7.13 from 9 for average survey results of applied mentioned methodology, and also it is 0.825 for research reliability. Research limitations/implications: of this paper suggest that the wide use of the other non-statistical techniques of quality engineering can be achieved with simple programming in excel and lean approach. Even more advanced topics in fuzzy circumstance can be applied with this methodology. Originality/value: of this research is extracted from three matrices of QFD, one matrix of VE and assessment table of lean approach for prioritising the control tests in product design of bullet-head drill 27.8 inch HSD.