Re: compressed air vs. screwed pipe

On Thursday, September 27, 2001, at 12:49 AM, SARE, RALPH H. wrote:
> Victaulic has limitation the very reason it was
> suggested only for fire water,  compressed air plus HVAC cooling or
> what we
> term as Category D piping. Flammables are not Category D and falls
> under the
> restriction stated in 314.
>

         I would like to bring up some rare case downfalls of victaulic. These are just problems I have run into in the field. Rust. I was once called in to repair an air over water fire line that ruptured at the coupling because one of the two bolts rusted and broke. Upon further inspection most of the bolts were shot. We ended up welding the joints on a weekend with the fire dept on site since it was the main fire line. It was costly.So watch out in high humidity corrosive environments.

         While I myself often use victaulic on temporary piping. Emergency crossovers, bypasses etc. The fact that it installs quickly, and easily is often its downfall. People get in a hurry and fail to properly support the piping, gaskets are often torn, or pinched and pipe is rarely laid out straight. I have seen companies throw day labor at vic. lines armed only with a wrench and a bucket of grease.

         It moves all over the place, even when using the rigid couplers, and requires more frequent supports.

         Gasket failure. I have seen multiple gaskets fail for various reasons. Selection, instillation, operating conditions you name it. Have you ever tried to replace a gasket in the middle of a run? For these last two reasons we have built a set of line-up clamps that will hold the pipe allowing you to remove the clamp cut the gasket off and weld the joint.

         Final cost. Vic. lines are more time consuming to insulate they also require different jacketing (sometimes). Additional supports add up quickly as well, and if a poorly installed line has to be tweaked the cost will skyrocket. I have been in on one job where the final installed cost worked out to be higher than if the piping had been welded. You need also account for shipping costs. We came up short several 6" 90's once and the cost of getting them to us when we needed them plus there cost was higher then grooving a couple of 3" joints and welding them on to a 90 that the supplier keeps in stock. Of coarse if you are not in the sticks then this is probably not the case.

People who give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety,

         Benjamin Franklin

[Non-text portions of this message have been removed] Received on Thu Sep 27 10:37:00 2001