Preloaded Joint Analysis Methodology

In Preloaded Joint Analysis Methodology, you'll learn ...

• Bolt, nut, and screw geometry & terminology standard in the industry as applied to the typical bolted joint
• Eight major concepts covering the loads, the corresponding failure modes, and the methodology used to calculate the respective values and, ultimately, the margin of safety of fasteners
• Application of the analysis to four common bolted joint configurations as presented in four respective examples

Overview

Preview a portion of this course before purchasing it.

Credit: 3 PDH

Length: 46 pages

Much of the material presented here was first compiled in NASA Technical Memorandum 106943, Preloaded Joint Analysis Methodology for Space Flight Systems. Chambers, 1995 [1]. This is one of the best compilations and explanations of the bolted joint, having pulled many of the equations from Shigley & Mischke: Mechanical Engineering Design [2] and Bruhn, E. F.; Analysis and Design of Flight Vehicle Structures [3].

However, all stop short of putting everything together in a cookbook manner to guide the engineer through a complete and combined analysis. This course intends to review the methods for joint analysis and correct that with a recipe and examples in the final section.

As we begin this course, the reader will first review the bolt, nut, and screw geometry & terminology standard in the industry as applied to the typical bolted joint. Next, we will dive into eight major concepts covering the fastener loads, the corresponding failure modes, and the methodology used to calculate the respective values and, ultimately, the margin of safety.

Along the way, we will explore the derivation of several of these equations. Finally, we will put it all together by applying the analysis to the four common bolted joint configurations as presented in four respective examples. These examples will provide an excellent “go-by” from which the reader can either perform the calculations by hand or develop their own Excel, MathCAD, or other software-based models for repeated analytical use.

Specific Knowledge or Skill Obtained

This course teaches the following specific knowledge and skills:

• Bolt/nut/screw geometry and terminology.
• The fundamentals and purpose of a preloaded joint.
• The variations in joint stiffness and elasticity for differing configurations.
• Common modes of failure within the fastener.
• Common modes of failure of the fastened material.
• The criteria for joint gapping.
• The failure modes of the nut and threaded insert.
• The applicable preload and respective torque.
• The effects of lubricant and locking features on selecting preload torque.
• The effects of temperature and relaxation on preload.
• The equations for effective analysis by following 2 examples.

Certificate of Completion

You will be able to immediately print a certificate of completion after passing a multiple-choice quiz consisting of 20 questions. PDH credits are not awarded until the course is completed and quiz is passed.