Explosive bolts
These explosive bolts are designed to be a cheap and compact separation actuator. A small explosive charge within the bolt causes it to fracture on the groove.
The bolt is an assembly of two components. The first is the brass main body which provides the structural strength of the bolt. Each bolt is 1/2" in diameter and can withstand up to 900 pounds in tension before failing.
The second component is the charge casing, which can be easily separated from the structural component of the bolt. This section contains the charge, the ignitor, and sealant. The sealant consists of a ball bearing and silicone. The silicone provides a soft seal to prevent the charge from escaping the casing and the ball bearing provides a hard seal when the charge detonates, cutting the igniter wire and sealing the chamber inside the bolt. The other end of the casing is sealed with a PTFE plug and silicone. The main bolt can be installed normally without the charge casing allowing for safe handling before flight. Upon final assembly, the charge casing easily screws into the bolt body and the ignitor is attached to the ignition board. Below is a video of an earlier version of explosive bolt being tested behind a blast shield to identify the explosive force and amount of sparking the bolts have. |
An assembled explosive bolt
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