MIL-HDBK-3 3 8B

SECTION 7: RELIABILITY ENGINEERING DESIGN GUIDELINES

Each of these elements can be tailored to meet the specific needs of each system. Reference [1] "Parts Selection, Application and Control" provides generic guidance in the development of this process.

Each of these elements are discussed in the following subsections.

A comprehensive PMP defines the manner in which each of the aforementioned elements will be addressed. It should identify the responsible personnel and include a milestone schedule. This plan can also be tailored in accordance with specific requirements of the system for each of the PMP elements. Tailoring should be accomplished considering:

(1) Development Cycle Time (6) Budget (2) Warranty Period (7) Screenability (3) Maintainability (8) Preventive Maintenance (4) Cost of Failure (9) Customer Requirements (5) System Characteristics (10) Severity (or Criticality) of Failure (a) volume (b) weight (c) performance (d) operating environment

Understanding, defining and then implementing all the tasks involved in a PMP program is the key to its success. The representation and active participation of the following disciplines, as a minimum, are necessary to enable, in a concurrent engineering fashion, an effective PMP:

(1) Parts (components) engineering (3) Design engineering (2) Reliability engineering (4) Manufacturing engineering

Successful implementation of a PMP requires a disciplined approach, and must have management participation and support to ensure cooperation among disciplines and resolve any differences based on the ultimate impacts on cost, schedule and performance.

7.2.1 Establishing a Preferred Parts List (PPL)

In the course of a design effort, equipment designers need to select the parts and materials to be used to meet specified equipment requirements for performance, reliability, quality, producibility and cost. This selection task is greatly enhanced if the designer has a list of preferred parts available to help in this selection process.

Preferred parts are those whose quality and reliability are well-known to the industry, and are probably parts that the company is already using in other equipments. Without a preferred parts list (PPL), designers may tend to choose parts in haphazardly. The result is the uncontrolled proliferation of parts throughout a manufacturer's product line, all varying in performance and reliability. All potential candidate parts should undergo an independent assessment before being

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