AP Explosives manufactures cord relays. Cord relays provide accurate delay between blast holes in a row or cross in a multiple row blast. Cord relays are of 2ms delay detonators of the same delay timing placed in opposite direction specifically designed plastic component.

Cord relays are bi-directional. The plastic component has a provision for hooking of detonating cord at either ends. The delay timings are printed on the plastic component.



These are used in conjunction with detonating cord trunk lines in open casts, coal mines, quarrying, civil construction, underground metal mines.



1. Being non-electrical, they are immune to electricity sources such as stray current, static electricity and radio frequency energies.
2. They are simple to use and bi-directional
3. The hook for the detonating cord provides two to three surface detonating patches, thus reducing the misfire risk.
4. Initiation is sequential reducing the problem of overlap
5. Since each delay can be controlled by using different delay intervals, there is lesser vibration

Cord Relays are available in intervals of 17 ms, 25 ms, 42 ms, 50 ms, 65 ms, 100 ms, etc.