Jump to content
APC Forum

Shock and friction sensitivity tests


Recommended Posts

Posted (edited)

Hi, a member of our national pyro forum managed to do sensitivity tests of some mixtures.

 

Rating of sensitivity: from 1 to 10.

Methods of testing:

-shock : dropping a 1,450kg iron weight on an iron plate from 100cm.

-friction :

A) rubbing a 500g hammer on an anvil

B ) grinding into granite mortar and pestle with unpolished walls.

 

1. KClO3/S 67:33

-Shock test - explosion (9/10)

-Friction test - A explosion with minimal pressure ; B explosion with minimal pressure ; (10/10)

Overall sensitivity 9,5/10

 

 

2. KClO3 / S/ Al (spherical) : 68/20/12.

-Shock test – explosion. (9/10)

-Friction test - A explosion with minimal pressure ; B explosion with minimal pressure. (10/0)

Overall sensitivity 10/10

 

3. Pb3O4 / Al : 9/1.

-Shock test – explosion. (9/10)

-Friction test - A explosion with minimal pressure ; B explosion with minimal pressure. (9/10)

This mix seems to be slightly less sensitive than mix N=1

Overall sensitivity 9/10

 

4. H3 - KClO3/ C : 75/25

Shock test – 2 ignitions of 5 attempts. Explodes from a very powerful hammer blow. (4/10)

Friction test - А – 1 crackling from 5 attempts, no ignition. B – Cracklings occur whith energetic grinding, but no ignition.. (6/10)

Overall sensitivity 5/10

 

5. KMnO4/S/Al : 80/12/18

Shock test – easy explosion. (10/10)

Friction test - A explosion with minimal pressure ; B explosion with minimal pressure. (10/10)

Overall sensitivity 10/10. This is the most sensitive and dangerous mixture!

 

6. KMnO4/S/Al : 60/20/20

Shock test – explosion (9/10)

Friction test - A explosion with little pressure ; B explosion with little pressure. (9/10)

Overall sensitivity 9/10

 

 

7. KClO3 / bright Al : 70:30

Shock test – 1 explosion and 4 failures. Explodes from a powerful blow with a hammer. (5/10)

Friction test - (А)– failures; (B) – 2 ignitions of 5 with energetic grinding. (6/10)

Overall sensitivity (5.5/10)

 

8. CuO / Al : 80/20.

Shock test – 4 explosions and one failure. Explodes from a powerful hammer blow. (8/10)

Friction test - (А ) – fails; ( B ) – 4 of 5 ignitions with energetic grinding. (6/10)

Overall sensitivity (7/10)

 

9. KNO3 / Al / S : 2 /1 /1

Shock test - fails. Sometimes it explodes from the powerful hammer blow.(3/10)

Friction test - (А )– fails; (B) – 2 ignitions from 5 with energetic grinding. (3/10)

Overall sensitivity (3/10)

 

10. Granulated BP – KNO3/C/S : 75/15/10

Shock test - fails. It did ignite once from a powerful hammer blow, but just once, It was hit afterwards without effect (2/10). Ignition could be due to iron spark

Friction test - fails. (1/10)

Overall sensitivity (1.5/10)

 

11. NH4NO3 / C : 76/24

Shock test - fails. (1/10)

Friction test - fails. (1/10)

Overall sensitivity (1/10)

Edited by 50AE
Posted (edited)
I'd like to see some KCLO4 tests also. It's known as "safer" oxidizer, but how much? Edited by ZIP18PL
Posted

I'm also curious how the rating system was done. It looks to be assigned by the tester, not actually related to any numerical data. For instance, H3 exploded 2 out of 5 times by the drop test with a rating of 4/10, but KClO3/Bright Al exploded 1/5 times and has a rating of 5/10. I think the testing is good, but some numerical data would perhaps be more telling. The drop hammer test for instance can be used to determine the impact required to set off a certain composition. Typically the minimal required impact to initiate an explosion and the height required to set it off 100% of the time are given.

 

Also, just to clarify, you do use commas to separate whole numbers from the decimal, correct? The weight you mentioned would be over a ton by the convention I am familiar with.

Posted

I don't like it, but the guy adds more points because the mixture was "exploding" instead of "igniting". Maybe he ment "detonating" and because of this he adds more points. I will ask him about it.

 

Yes, the comma is used the way you say it ;) The hammer weights 1450 grams :)

Posted

That is very interesting to say the least. I agree with mumbles there should be a bit more explaning as to how the rating number was derived. Is there any mention of purity of the chemicals?

 

Makes me a little less comfortably with H3, I thought it was more "stable" than that. And my what big hammers Bulgarians must have :lol: !

 

 

 

×
×
  • Create New...