David Archer

Analyzing Bolted Joints for Clamp Load and Joint Stress

Bolts generate a lot of clamp load in a small area. That’s good for tight joints, but it can also create stress.

April 10, 2017

Many important considerations in bolted joint development are often overlooked. While estimating the bolt tension achieved for a given tightening strategy is certainly a common focus, the effect of load on joint components is less fully discussed and understood.

Fastening Do’s and Don’ts

After writing this column for six years, I understand the need for brevity. With that in mind, I thought it would be useful to summarize some of the key points that I’ve raised in the past.

David Archer

April 1, 2013

I have included the issue in which each column appeared so you can delve into the topic in more detail if desired. As always, please feel free to contact me with your questions, comments or observations.

The Effect of Sample Size on Test Results

David Archer

September 4, 2012

One of the more interesting aspects of conducting joint tests for manufacturers is the question of sample size.

Fastening Threads: Problems Solved

David Archer

May 1, 2012

Bolted joints are the vast majority of our consulting business. Our work is divided evenly between validating joints under development and troubleshooting problems with existing joints.

Fastening Threads: Getting with the Program

David Archer

February 1, 2012

Programmable torque tools have become popular in recent years, due to quality initiatives.

Fastening Threads: All Screw Head-Drive Features Are Not the Same

David Archer

August 29, 2011

Impact head and drive style selection can have a profound effect on assembly productivity. To examine this, we recently conducted a study focusing on machine screws.

Fastening Threads: Every Picture Tells a Story

David Archer

May 26, 2011

Most bolted joints enter production with installation torque based on textbook estimates.

Fastening Threads: Even If It Ain't Broke, Make It Cheaper

David Archer

December 22, 2010

Reducing cost requires action with potential risk, whose objective is often viewed as compromise. However, the need for constantly improving product value is not going to go away. Here are three ways to address cost reduction.

Fastening Threads: Losing Weight Is Always a Challenge

David Archer

August 30, 2010

The growing desire to reduce fuel consumption has caused manufacturers of all modes of transportation to be more willing to implement the use of light-weight materials, even where there is a cost penalty. However, use of new materials in a given application always carries some risk that must be mitigated through analysis and testing.

Fastening Threads: More Data, Less Knowledge?

David Archer

April 29, 2010

Just as both the quality of the joint and the quality of the joint designer’s knowledge base will be limited by reliance on numerical analysis, the same limitations occur when experience and applied experimentation is all one has to draw from.