The post is great and informative. As technology upgrades, fastener supplying companies should also check their fasteners qualities and should maintain it.
There are many fastener supply companies which provide fasteners in quantity but when one check their quality, it goes down. So, time to time, companies should also take responsibilties to provide quality in fasteners.
Hello Ann, I asked the very same question and sometimes they did not. There were times, granted not many, when emergency landings had to be made due to cowlings or flight surfaces coming loose and vibrating uncontrollably during flight. Of course, this can affect the airworthiness of the plane and consequently provide exceptional drag. It was always amazing to me how uninvolved some pilots were relative to pre-flight inspections. The "walk-arounds" recommended were sometimes cursory at best. My experience was during Viet Nam and there were so many aircraft coming and going at the Ogden Air Material Area (OAMA) it was impossible to say what part belonged to what aircraft. They were labeled with a date and placed in a special bin. Then you wait for a phone call.
This statement: "A secondary issue arises: finding safe and reliable methods of fastening assemblies that can protect against fastener loosening while minimizing assembly and maintenance costs. These methods must provide complete assurance of joint integrity under the severe conditions of shock, vibration, and thermal cycling common in aerospace environments" brought to mind Apollo 13 - if I recall correctly the explosion was caused by a defective part off the assembly line. I would be a lot more interested in maximizing safety then in minimizing the costs of the fasteners...
Robert--very interesting post. I think fastener technology has greatly improved over the last 20 or 25 years. During my "tour of duty" in the Air Force, we would sweep the runways three times per day for components that actually fell off the aircraft. It was amazing to me the parts we found. Our sweeper had the capability of lifting a part weighing up to 100 pounds--and we found them. Cowling, hundreds of screws and bolts, nuts, etc. you name it. Believe it or not, we never had an accident, to the best of my knowledge, as a result of components vibrating off but, I certainly don't know why not. The technology has definitely advanced since those days--thankfully.
The only issue that I have experienced with threaded inserts is the special tap needed for the OD of the insert. I have been in shops where they might only have one Helicoil tap for a certain ID thread. Production stops when the guy that keeps the tap in his tool box is on vacation.
I use steel inserts in two cases. One where a bolt will be removed repeatedly, or I have to fix a stripped out hole. I think the later is where most inserts are used. In many cases the insert has a stronger holding potential versus the original thread. I only wish I could get some of the more exotic sizes cheaper.
Machine vision and video streaming systems are used for a variety of purposes, and each has applications for which it is best suited. This denotes that there are differences between them, and these differences can be categorized as the type of lenses used, the resolution of imaging elements, and the underlying software used to interpret the data.
As today’s product design cycles are held to tighter schedules and budget constraints, it’s becoming even more critical to consider human factors up front to catch and fix problems during the initial development stages, when it’s faster and less costly to do so. Overlooking human factors at the beginning of the design cycle could lead to poor user experience, a decrease in effective product performance, and an increase in safety risk to the user.
Plastic part manufacturers are always looking for ways to reduce cycle time and get more productivity out of their injection molding machinery. One of the longstanding constraints in injection molding production has been cooling time. Removing parts from the mold before they have cooled induces warping or shrinking. But wait time works against productivity.
Editor’s Note: This is part 1 of an in-depth look at six added-value opportunities -- adjacent to the aluminum extrusion option -- that OEMs can integrate to upgrade supply chain interactions from basic buyer-vendor transactions to critical collaborations on strategic, single-source solutions.
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