Reprint from LINK, Summer 2020
A number of years ago I owned an old John Deere tractor that was clearly showing its age. As I tooled around my yard cutting the grass I noticed that the engine was laboring more and more and it was consistently blowing oily blue smoke from the exhaust. I knew it was time to either retire the tractor or rebuild the engine. Although I had never done it before, I decided I would try my hand at rebuilding the engine.
Reprint from China Fastener World Magazine, Vol. 190
Heat treating fasteners is a complicated topic with many details to keep track of. The following are some questions and answers that should shed some light on basic concepts.
Reprint from Fastener World Magazine, Vol. 175
About twenty years ago I was working with an automotive foundation brake supplier when catastrophe struck. One of this company’s calipers utilized a Collette Style Pin brake caliper design. These calipers operate by sliding along a two piece pin system. There is a Collette Pin with a tapped hole in the head and a Mounting Bolt. The Mounting Bolt connects the face of the Collette Pin to the back side of the Piston Body Flange, providing unfettered access for the caliper bracket to slide along these pins when the brake is functioning.
From Fasteners Technology International, February 2014
What do many lawn mower blades and automotive spring steel clips have in common? When considering their applications, probably very little, but in their product realization, they likely have both employed Austempering (a heat treating process) as their method for strengthening and toughening. Although over 75 years old, Austempering is a heat treating process that has really only become practically viable and commercially employed in the last 40 years. Austempering will likely never supplant conventional quench and tempering processes for the majority of threaded fastener applications, yet some of the advantages are so compelling that there will always be interest and activity in expanding the current application field. At hardness levels above 40 HRC, Austempered parts demonstrate improved mechanical properties such as toughness, ductility and strength over their quench and tempered counterparts of comparable hardness. Austempered parts undergo significantly less distortion, which reduces the subsequent cost of post heat treatment remediation.
Since this technology has direct application for the fastener industry, both now and well into the future, it is advisable for practitioners of the industry to have an understanding of the basics and enough information to consider what future possibilities might be waiting out there. The goal of this article is to provide a simplified explanation of this complex process and to explain some of its more compelling advantages.
From Fastener Technology International, February 2013
A couple of years ago, I took up Sporting Clays, which is a shotgun shooting sport where the target, a four inch round clay disc, is presented to you in two different ways over a course composed of maybe 10 to 15 different stations. Although I am still “developing” my skills, I have found this to be a fun and challenging sport. I have enjoyed it so much that for my birthday last year my wife presented me with a year’s subscription to one of the sport’s magazines. This too I have enjoyed, but it quickly showed me, with no lack of frustration on my part, how very little I really know about the sport. I couldn’t tell you what the different target presentations are intended to represent, how competition is properly scored and for that matter what much of the terminology means.
In much the same way, when I was confronted early in my career with the process of heat treating fasteners, all but a few basic concepts that I remembered from my beginning Engineering Materials class were unknown and cloudy. As I gained more experience, asked questions, learned how parts were manufactured, saw the process and participated in the industry’s technical community, I gained clarity and understanding. However, for those not normally engaged in technical activities or those new to the industry, I imagine that much about heat treating is shrouded in mystery. Why does one heat treat a fastener? How does it work? What is some of the important terminology? This article is intended to help give some simple answers to these questions and unwrap the mystery for those that have no reason or need to hold a metallurgy or engineering degree, but desire to know a little more about fasteners.
For the purposes of this article I will limit our discussion to basic carbon steel and carbon alloy fasteners. This covers the vast majority of fasteners, but certainly not all. Many specialty and highly engineered fasteners utilize more exotic materials that have special and unique metallurgy and often complicated mechanisms to improve physical properties. The bottom line is that this topic can be studied to great depths and there is much to know, even at the simplest level. This article will only touch on the most basic of these concepts.