Hi All,

 I've had requests for a S tube on the end of my placement hose doing ICF walls and then explain the dangers. Its someting I wont do but I understand why they want it to slow down flow. Why would you use one for what appears to be a large slab. And again dangerous and something that shouldn't make cover page.

I have them in the end of the boom...  

Good point Vasa! I cantb believe they put that on the cover!

I think todd have a job to do he is always promoting the world of concrete.

A good example of the dumb asses we have in the management end of our business

i used to use these for ICF walls but i stopped doing it because of the dangers. I switched to a 2 1/2" whip hose instead. We usually use a 10mm (3/8") mix at about 28Mpa and a 5-6"slump[. Works really well but i know everyone worries about blockages with that small of a whip hose so i have a piece of 2x2" Steel mesh that fits over the grate in my hopper, keeps all the crap out and help the pour go nice and smooth!

I am a member of the ACPA and this is the email I got about this cover.

Many of you may have seen the January edition of Concrete Construction magazine that prominently displays a double “S” device on the end of the concrete delivery hose. If not, you can view the digital link at http://www.concreteconstruction.net/table-of-contents/magazine.aspx.

Although contractors may request these types of devices to prevent the “free falling” of concrete, they also weigh too much and become dangerous. Should the hose move unexpectedly, these devices could cause a deadly injury to the person directing the concrete hose or to nearby workers.

For this reason, the ACPA does not recommend the use of  double “S” devices.

For more detailed information, please refer to the ACPA safety bulletin “Double “S” Bends Can Be Deadly” on the ACPA website www.concretepumpers.com. While you’re there, take a look at the hose whipping video. Can you imagine the injury one of those devices would cause if the hose whipped and hit a worker? Scary.

Safe pumping!

Christi Collins

Executive Director

American Concrete Pumping Association

Ph             614.431.5618        Fax          614.431.6944      

christi@concretepumpers.com

www.concretepumpers.com

We're not talking about the 'sudden movement' of the hose being caused by the operator moving the boom and the hose kncking the man off his feet.  It's when a plug occurs in the hose or attachment and there is air trapped behind the plug, and the plug releases with EXPLOSIVE FORCE.  You get a slug of concrete maybe 50 - 300 lbs or so (22 - 130 kg?) being propelled by a volume of air at up to 800 psi (5500 KPA)  The concrete coming out is like the buckshot from a shotgun shell, and the uncontrolled recoil of the hose and attachment is like a baseball bat to the head or body, if not worse!!

Remember your highschool physics - for every action, there is an equal and opposite reaction.  There is TREMENDOUS power stored in that compressed air, and it's just waiting to be released, what happens when it does is up to you.  But you're the guy with the remote in hand, away from the worst of the resultant action.  (unless you also are the hoseman, which is another safety issue altogether)

The hoseman may not be aware of the danger, his wife sure isn't but she may find out, his kids will never understand, and his doctors, nurses, nuerologists and plastic surgeons are merely dealing with the aftermath, at best, at worst, it's another customer for the funeral home.

Whether the 'S' is made of steel or a 'gummy material' as you said makes little difference, as a pumper, you know full well that plugs are much more likely in elbows than straight sections.

The floor is now yours to make a good argument (try to make it so the victim's kids understand it, please) 

Until fines and or jail time are issued when operators knowingly do something "wrong" ,nothing will change.

You connect the rubber double 45 with a hose clamp?  

Of any of the homemade anti-splatter contraptions, I like Kris Leers idea of the traffic cone on the end of a single ended hose with no steel holding it on.

Here's a link: www.youtu.be/p-iiNcn6mQ  

Sorry, the link is:  www.youtu.be/p-iiN_cn6mQ   

(I use Google Chrome for a browzer, and I can't copy and paste into this forum.  So I have totype it in manually - any little error in syntax and it fouls it up)

I have been told that some states will not let you pump bridge jobs with out double 90's. It's written in the spec.

My answer is. " I do have a double 90, it is just above the tip hose." Plus I run pump in Z formation most of the time which helps also.

Dipstick you have to play it smarter. you know whe also have that double 45 on the pump, but since I have told the boss the slab crews don't want a double ender any more. my pump is changed to a real tip hose. And because of that the double 45 don't fit anymore. Yes I may not refuse to use it if the costumer ask for it but then first we have to change hose and that costs time. So most costumers then say leave it.

Dipstick, I feel for you , its not a matter of if , its when someone gets hurt they will change their minds,i worked for a company it was common place to use them I refused , took them off my pump, I would however put a metal reducer and a 4" whip hose to accomodate the customer , this always worked for me, then one day a hosemans leg was broken, compound fracture , needless to say double 90s on the end was a thing of the past, had a few out of town guys that would still use until customers started requesting them and their double 90s, after a few days off they began to see it the owners way, when it cost him thousands in lawyer fees and medical bills I promise you he will change.

Todd Don’t you have that video of the tip hose exploding from a plug releasing?

The s-bend issue is also partly concerning this.

One of my concerns was commented on in this post with contractors “demanding unsafe practices” on sites. Just because Old unsafe practices are “grandfathered” into working practices that even MFG’s don’t allow anymore I don’t under stand how they can force this into job site practice, but it seams from this they still do.

I have even seen it my self.

I have been on jobs where you spend a full day in safety orientation just to get onto the site, and then the contractor forces the customer to do something with the pump that’s not allowed.  

I am not trying to stir stuff up, but with all the I phones out there if the guy had a short Video on their phones they could show a contractor of that tip hose blowing it might open some eyes. What do you guys think.?

Here it is. I think the ACPA did this test. ACPA rocks.

http://video.concretepumping.com/videos/852/hose-whip

We use 4 inch "double 90s" or quad 45s on our residential wall pours. No issues,any good operator knows when he/she has a plug before hand. If your pumping at a steady pace,be it fast or slow,as soon as the pump changes it's rhythm,concrete stops coming out or other,you stop the pump and investigate BEFORE something happens.