Removal of Ergo-Tech
Blind Bolt with Hand Electrical Discharge Removal Tool
A new method of removing Ergo-Tech® blind bolts, which utilizes
a handheld electrical discharge process, is evaluated. Currently,
the most common method of removing blind fasteners involves
drilling the head of the fasteners to a point where the shank can
be punched out. In some situations, when the back side of the blind
fastener is accessible, this portion can be ground or machined off.
Both approaches are time consuming, messy, and unsafe for
technicians. There is also a high probability of damage to the
surrounding structure associated with the current processes.
Additionally, machining chips which are difficult to contain can
create foreign object damage (FOD).
A new fastener removal system which utilizes the principle of
electrical discharge machining is evaluated. The system is
portable, and includes a handheld gun which is approximately the
size of a typical fastener installation tool. This paper covers the
evaluation of this approach for removing the Ergo-Tech® blind
fastener. The electrical discharge method involves removing a
portion of the head of the Ergo-Tech® fastener in a small contained
Numerous benefits are found in using an electrical discharge
handheld machine for removal. Ergo-Tech® fasteners can be removed
in seconds instead of minutes. The removal process is silent, FOD
free, and requires minimal force to be applied by the technician.
And, the entire removal system, which is approximately the size of
a travel suitcase, is lightweight and portable. All liquids and
debris created by the removal process are contained within the
system, and collected within the internal filtration system for
simple operation. This system is promising for original equipment
manufacturing facilities, maintenance repair and overhaul
locations, or operating bases.