17 replies to this topic

[zookeeper]

I had a display recently and a Lidu Brand triple salute (stacked) shell detonated in the mortar.

Has anyone else had similar problems with this product, or was it just a "fluke"?


...Just asking, to see if these may have a problem.

[paul]

Sorry if I don?t really answer to your question, but as a non-professional I just have to ask: Did it explode while setting up the display or did it so "just in the mortar" while the display was fired ?

I can imagine such a salute will rupture even the hardest mortars.

[CaptainAmerica]

First, I'll appologize for not answering your question. Next, I'll appologize if it sounds as if I'm getting on your case. But please be careful with your language. Shells do not by definition "detonate." In order for a substance to detonate it must create a wavefront moving faster than the speed of sound. The only reason I mention this is that the government would love to outlaw fireworks in this country and if we in the business/hobby talk about our products as high expl*sives the government will do just that.

I hope others here can be of help with your question. Be safe and have fun.

[pyrotrev]

Whilst I can understand concerns about the powers that be, it is a fact that under certain failure modes shells can d""onate, and when they do cause great damage to racks, with a potential for injury to both audience and firers: a number of high profile accidents have been caused in this way. If a colour (not salute) shell functions normally (in free air) the process is deflagration, but some types will progress to d"""onation if they explode confined inside a mortar, whereas others will merely "flowerpot" - kind of a violent mine effect. What determines the effect is not completely defined but there are some guidelines:
1) Cylinder shells are more likely to exhibit this effect than round shells, presumably due to greater pressure build up causing the transition from deflagration more easily.
2) Less rigid (PE/paper) mortars lessen the likelyhood of the effect, whilst rigid (GRP/steel) mortars make the effect more likely, presumably due to greater rate of pressure rise in the more rigid containers.
3) Shells with a flash burst or flash enhanced burst exacerbate the effect.
4) Certain star mixtures seem to be more prone to it than others.
5) Most flash salutes rely on the effect anyway - Shimizu records the various velocities of different flash mixtures for those who are interested.
I did some safety testing last year with 3" cylinder shells (silver coconut palm) which I fired upside down a very long way away. Results were quite spectacular, the GRP mortar was completely destroyed, the largest bits were only 4" across . More worryingly the adjacent tubes were completely crushed, one partially shredded and scattered 15...20ft . The rack was completely trashed, and the high tensile alloy stakes securing it were seriously bent. It's made me rethink safety strategy a lot......

RESPECT (....and stay green)

[Mumbles]

This all goes back to the arguement of if flash powder is capable of detonation. My personal feelings on the matter happen to be that it can't.

Anyway, the shell was probably a fluke. One must expect an occasional failure. Chinese mass produced fireworks may have more failures due to fast working speeds and lower quality materials. From talking to people in the area, they get around 4-5 duds or so per thousand. This includes low break, hangfire, flowerpot, basically anything not functioning correctly. They say at least 1 or 2 of these could be prevented with better inspection of the shells and removing the visibly faulty ones. Stacked shells have a higher failure rate. More stress it put on the bottom most shell. With flash, if one fails, they all fail.

[zookeeper]

Did it explode while setting up the display or did it so "just in the mortar" while the display was fired ?

I can imagine such a salute will rupture even the hardest mortars.

Sorry, I'll be more specific (it was late, after the show, and I was tired...)

This event happened at a professional public display.

The shell's safety fuse was lit, during the display, quickmatch leader burned as normal, and the shell did not lift. The mortar was HDPE and was in a wooden rack, it was shredded (we're talking "toothpicks" here).

I think what may have happened was that one of the stacked shells jammed and was overpressured, causing the premature break.

I think it was a fluke, Lidu has very good quality control, just wondering if anyone else has had a similar problem with "stacked shells", "double bubble" or "peanut shells" in a display.

But please be careful with your language.

Point well taken...

[zookeeper]

If a colour (not salute) shell functions normally (in free air) the process is deflagration, but some types will progress to d"""onation if they explode confined inside a mortar, whereas others will merely "flowerpot" -

These were triple salutes, and they did all go BOOM.

The display lighter did get some cuts and bruises from the flying debris, but fortunately no "real" damage was done.

[pyrotrev]

I think it was a fluke, Lidu has very good quality control, just wondering if anyone else has had a similar problem with "stacked shells", "double bubble" or "peanut shells" in a display.
Point well taken...

I've never had any problem with Lidu stuff, IMHO some of the best quality manufacture in China, and they're getting into some very pretty effects now too. I have had other brands of "peanut" shells malfunction though, normally the bottom unit would flowerpot, I presume it gets "squashed" between the upper and the lifting force, manufacture needs to be better than average in these I guess.

Edited by pyrotrev, 08 June 2006 - 09:36 AM.

[adamw]

I'm suprised it was a Lidu product - but it can happen to anybody now and then. Pity it was a triple salute - sod's law!

Regarding detonation - it's a tricky subject - some would say that Shimizu has demonstrated flash powder to be capable of detonation. Either way, you may as well treat it as if it is that sort of explosive.

[Night Owl]

The only experience I've had with Lidu shells is 3" can ones, the funny thing was when they fired and the tubes were cleaned we found the can cases left in the tubes, turned out they were just round shells wrapped in a tube made to look like a cannister shell

Edited by shell shooter man, 13 June 2006 - 11:01 AM.

[Amleth]

The only experience I've had with Lidu shells is 3" can ones, the funny thing was when they fired and the tubes were cleaned we found the can cases left in the tubes, turned out they were just round shells wrapped in a tube made to look like a canister shell

Heh. I suppose that's one way to get a consistently nice, round break out of a 3" cannister shell...

[iggy]

yep have had a 6" penut go in the tube before thankfully it was very well burrid in the ground a good heavy clay soil the shell was a doubble break 6" sunsong silverpalm with silver umbrella beautiful shells but this 1 totaly went wrong when we went to investigate after the show was over i will add we were firing from the oposit side of a lake here crowd were about 300 meters away hence most of the show was 5" claiber upwards the tube a fiberglass one had been split lengthways and the bottom of the tube had be shattered this was our first and last time useong large caliber peanut shells we regularly use 3" and 4" lidu and other brand peanuts and have not had any problems appart from the fuesing on nantongs 3" red white and blue the first shot literaly riped the fuse from the other shells hence alot of unfired shels this was at our testing site so thankfuly could refuse them acordingly so the would work for the shows.
also i have noticed that sunsong larger shells have massive lift charges on them hence we no longer use there larger shells they are tube killers

[zookeeper]

Thank you all for your thoughts on this subject!

I do enjoy this forum to "de-stress" after a display.
--to the Administration!

I'm suprised it was a Lidu product - but it can happen to anybody now and then. Pity it was a triple salute - sod's law!

Yes, I was very surprised as well. If it had been a Horse brand or Jumping Jack, I would've expected nothing less than a flowerpot. We have had great success, over the years, with Lidu, Vulcan/Shogun, Sunny and Ricasa.

The Lidu triple salute, in a 10 shot finale chain, is a fantastic way to put a vast amount of product in the air, using a minimal amount of equipment. I think I will shoot them electrically, from now on.... just to be safe

[BurlHorse]

I had a display recently and a Lidu Brand triple salute (stacked) shell detonated in the mortar.

Has anyone else had similar problems with this product, or was it just a "fluke"?
...Just asking, to see if these may have a problem.

I've had plenty of trouble with the Lidu "double Bubbles", Salutes and Color/Effect shells, from their being to"fat" to drop in the mortar to them just going off, I hate 'em. They like to eat racks and I have one guy I Lead shoot for who insists on sending me truckloads of double bubbles, He does it to all his lead shooters and had many a near mutiny on the 4th.....In a plural word....Lidu Sucks.........

Stay green

Bear

[zookeeper]

I've had plenty of trouble with the Lidu "double Bubbles

Ok, problem noted...Thanks!

They are a "tight" fit for me as well, but not oversized, I don't think.


Were they a 2005 or 2006 production run or other date?

In a plural word....Lidu Sucks.........

What brands would you recommend, or have given you the least trouble?