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Pipe cover
4

Pipe cover

Pipe cover

(OP)
We are finishing a geothermal pipe system and on top of the insulation we are covering with galvanized steel sheet, unfortunately we found out that they are stollen inmediately. Does any one have experience with a solution to stop steeling other than contracting guards over 10 kmts every 100 mts. Some times we welded the sheets when we used calcium silicate, but now we nare using rockwool, a material that would melt if over heated, any sugestions?
pictures at www.geocities.com/simanmecanica , (under construction)

RE: Pipe cover

If a metal strapping band can be passed around pipe and cover, maybe a metal strapping system with bands located every meter or so will hinder thieves from removing the galvanized sheet covers.

http://www.welding-advisers.com/

RE: Pipe cover

haha... no wonder the steel prices are increasing like mad.

back to the issue. Eh... melting Rockwool. What density are you using? would you consider other finishing option?

Base on the material used as mentioned by you, I assume you are insulating hot pipes.

You can either apply Foster mastic as a finishing. If indoor, you can consider Foster 30.36 & outdoor, Foster 35.00. there will be mesh involved in applying this. Or, get alum. foil with self adhesion on one side and stick it to the insulation materials as a fininshing.

There are pro & cons in whatever method or material you chose. For instance, if the pipe is vertical, then the above mentioned both option may be considered. If it's horizontal, I will suggest more of using the Mastic.

Oh yes, Fibreglass fabric may be a good option as well.

By the way, in which country do you require the material. I may be able to advise some suppliers for your consideration especially in asia.

Cheers

RE: Pipe cover

(OP)
We can´t consider other options because the material is already here, ( maybe for future projects we could sugest it). In another project we used a metal cage but it was very expensive. I don´t know the density of the wool but I may ask our client.
We are in El Salvador, in a 40 MW power increase project. All information is very welcome.

RE: Pipe cover

Presumably the locals are taking the sheets because they are large enough to be usable as roofing/siding material?  If so, can you cut down the sheets so they are in a less-usable form?  Or, as one poster seemed to suggest, glue them onto the insulation using a mastic or epoxy?

RE: Pipe cover

(OP)
And .... yes they are hot pipes, for steam and hot water.

RE: Pipe cover

Hmm.  One last suggestion: stencil the biohazard and/or radioactive waste hazard symbols onto the sheets.  This may or may not deter thieves, but might dampen subsequent resale of the sheets to other people.  Also, it would provide you with the ability to track down the sheets (just drive thru local villages looking for the symbols...)

RE: Pipe cover

(OP)
Cutting down, that would be expensive because they hand installed. Stenciling, we´ve done it before, but the truth is they are taken by very poor villagers, and we can´t put them to jail you know. This are good ideas.
One idea I had was to make them larger too and this idea was sumitted to the client but they did´nt like it

RE: Pipe cover

If you can insulate them, i would fit an electric fence controller or 12 to the sheets.

RE: Pipe cover

(OP)
Ambiental considerations would not allow it, because there are a lot of children playing around.

RE: Pipe cover

Pay the villagers to wrap the insulation with leaves bound with twine, which you also pay them to make.  Do it every year; make a festival of it.  Award prizes for particular neat and/or artistic wrappings.




Mike Halloran
Pembroke Pines, FL, USA

RE: Pipe cover

(OP)
The client has decided to weld the sheets with tin, does any one know a last generation technology or new equipment please....

RE: Pipe cover

I guess you could use a lockseam and/or solder.

That may slow down the thieves to somewhere near the replacement rate...

Mike Halloran
Pembroke Pines, FL, USA

RE: Pipe cover

(OP)
Any information of where to find lockseam designs? or procedures...
THANK YOU

RE: Pipe cover

There are a number of ways to make a lockseam; the choice usually depends on which tooling you have.  You may be familiar with standing seam metal roofs, formed from simple and slightly asymmetrical pans.  The standing flanges from adjacent pans are folded over, sometimes once, sometimes twice.  Similarly, round metal tube for air distribution systems is commonly shipped with the seam open, and many pieces nested.  The seam snaps together by hand.  Variations for rectangular tube may use two lockseams at diagonally opposite corners, which may snap together, or may require folding at assembly.  You can find examples at your local building supply house, or order from McMaster-Carr.

The point is, whatever shop is engaged to make the cover sections will probably have its own variation on a lockseam.  Some but not all snap together and stay together permanently.  

Some can be manipulated open again, given idle hands.  So you would supplement the lockseam with solder.  You will need a _very_ serious soldering iron; probably the kind you heat in a blacksmith's forge.

  

Mike Halloran
Pembroke Pines, FL, USA

RE: Pipe cover

(OP)
If we have Rock Wooll as insulation under the metal sheet cover, how do you close the lockseam?, there is no back support to press it...
Does any one know a modern system for soldeering, faster, more echonomical? I have 16 gauge galvanized sheet...

RE: Pipe cover

Wow, 16 gauge seems very thick for pipe cover.

On the other hand, it opens up the option of using a simple lap seam, closed by self-drilling screws and a few pop rivets.

Mike Halloran
Pembroke Pines, FL, USA

RE: Pipe cover

(OP)
Ups, sorry you are right, it is 26 gage. And we are already using rivets. And now what we are looking for is the cheapest an fastest welding procedure for it.

RE: Pipe cover

The smallest portable MIG welder you can find would probably work just fine.  Well, you might have to buy a slightly more expensive one to get down to the ~15A of welding current you will need.

Mike Halloran
Pembroke Pines, FL, USA

RE: Pipe cover

(OP)
Thank you

RE: Pipe cover

Same problem as in the Philippines, and any poor country.  Whatever is not bolted down or welded, is immediately stolen.  If these are permanent covers, say, not needing to access the pipes for a decade or more, could you apply the cover, coat with asphalt mastic, and encase the whole thing in concrete?  Just a thought.

RE: Pipe cover

(OP)
The thing is we are already covering the pipe, and all material was already bought, but your ideas sound right, I should investigate more on asphalt mastic... but won´t it melt?, I know there are lagging products like "eastasia" advised, though Foster did´nt answer yet.

RE: Pipe cover

At 26 gage, galvanized steel can be readily cut next to the welded seam, using a knife.  The stiffness of the seam even makes it easier to cut neatly.

At 22 gage or 20 gage, it gets harder to cut with simple tools.  Next time, if you are still limited to galvanized steel, buy that.

I thought about suggesting perforated metal (over foil) so it couldn't be used as roofing, but that would be useful for screening.  Then I thought about perf with really big holes, or hardware cloth, or chicken wire, but the truth is that there's always a market for 'free' metal.

Except maybe titanium.  They might leave it alone after trying to cut it.







Mike Halloran
Pembroke Pines, FL, USA

RE: Pipe cover

(OP)
Next time I want to suggest a better method, a lagging material I guess. I checked with Belzona, but their material is quite expensive;
Let´s see:

Fiber glass................. it breaks
Belzona......................expensive
Other polymers...............????
Titanium.....................$$$$$$
Foster.......................????????
Galvanized steel+lockseam....no back support
Galvanized+MIG...............melts Rock Wool?
Galvanized+(other welding process)? Brazing?
Electric fence?..............dangerous
Screws and rivets............used right now, no result.
Friction stir welding........???
Leaves+twine.................(smile
10 meters long galvanized....hard to take home?

Good mind exersice




RE: Pipe cover

You might need to insert a strip of fiberglass or a loose metal strip or channel to keep the MIG heat from melting the rock wool.  Or, the melting may be localized enough to ignore.  Brazing heat cannot be as localized and will melt more rockwool.

Friction stir welding is an interesting process, but it involves rotation of a nonconsumable probe, sort of like an endmill with no teeth, and simultaneous exertion of huge side forces in order to produce friction.  It's typically done on rigid thick slabs of metal in _very_ rigid machine tools.  Not a field process.

Belzona and other liquid/ paste/ goo coverings have the sole advantage that they cannot be removed in a form that is of any use to anyone, includng poor villagers.

If they can cut the axial seam of a long sheet of galvanized, they can also cut it circumferentially to make it easier to transport.  They might go to some effort to remove big pieces intact, so they need fewer seams in their shanty roofs.

I was serious about the leaves.  Natives here in SoFla evolved dwellings roofed with palm fronds.  They are surprisingly cool, durable and water resistant.

Mike Halloran
Pembroke Pines, FL, USA

RE: Pipe cover

Fibreglass- Breaks??? You may try insulation wool encapsulate with Fibreglass fabric. If it's for external weather, you can consider 0.4mm fabric coated with silicone. In asia, you can get a decent quality for nothing more than USD9.00/m2. These covers can be pre-fabricated & all skills will be provided by the fabricators. The advantage is you require less or no skill workers to install on site.

As for comments about expensive, it all depends on the project budget and what you are looking for. If cost is the main concern then maybe quality might be compromise.

If I don't remember wrongly, in the west Foster mastic or coating product is produce by HB Fuller. I wonder if you got the right contact.

RE: Pipe cover

(OP)
Mike:
Remember that although we have insulation the surface temperature is about 50° C and the leaves would become brittle very soon.
Eastasia: please send your mail, you can find mine at the beginning at that website.
There is another similar project starting now and for that it´s time to do something.
I got to HB Fuller site and they didn´t answear yet, I´´ll try again...
Let me do some research on insulation wood encapsilated with Fibre glass...

RE: Pipe cover

ok, time to look at this prob from another perspective.

The pipe carries hot water correct??   and passes by the villagers?  not for there use?

If you could strike a deal with the locals both could win.

Have them agreee not to vandalise the pipe insulation, and you will let them have unrestricted hot water from a single or two small taps....    Would a few gallons an hour be a prob?

If they continue to remove the sheets, remove the taps. they may learn the second time around...

Ken

RE: Pipe cover

Hi Cuyanausul:

I am eastasia. I couldn't login as eastasia after my last posting. Had contacted the admin but no reply so far.

Anyway, you may sent me an e-mail at iheinsulation@yahoo.com & I will sent you my main from there.

I couldn't get to your website as upon clicking  www.geocities.com/simanmecanica, it does not hyperlink over.

cheers

RE: Pipe cover

(OP)
The pipes carry hot water and steam, both are geothermal, not safe for humans to use. The client has help programs for villagers to get something in return, but the thieves are not satisfied. And also many people work at this projects, for example we had up to 700 workers at the top stage of the project.

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