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gt  
#1 Posted : 07 August 2017 10:29:29(UTC)
Rank: Forum user
gt

I am not a welder but I do know that welding rods have to be kept in storage which has temperature and humidity control.  Last week, during a safety inspection, I discovered that our engineers use an old upright fridge for storing welding rods.  I thought it was strange but then they told me that the workings had been converted so that the inside of the fridge is kept warm.  Now I think it is even stranger.  I haven't come across this before so can someone please tell me if it is normal practice?  Should I worry or should I pat the guys on the back for their ingenuity?

Thanks.  Graham

A Kurdziel  
#2 Posted : 07 August 2017 10:31:35(UTC)
Rank: Super forum user
A Kurdziel

I think that someone is taking the Michael

DaveBridle  
#3 Posted : 07 August 2017 14:37:29(UTC)
Rank: Forum user
DaveBridle

There is some truth in what they are telling you.

http://www.lincolnelectric.com/en-gb/support/welding-how-to/Pages/storing-electrodes-detail.aspx

Also adapting an electrical appliance for a a different purpose ....... (i'll let you deal with that one.)

johnmurray  
#4 Posted : 08 August 2017 05:49:54(UTC)
Rank: Super forum user
johnmurray

Keeping them in dry conditions is good enough. Some need to be kept hot prior to use; again, that is to control moisture absorbtion. Usually low-hydrogen rods.
gt  
#5 Posted : 08 August 2017 10:57:38(UTC)
Rank: Forum user
gt

Thank you each.  I'll pat the engineers on the back as I dispose of the fridge.

Graham

johnmurray  
#6 Posted : 09 August 2017 08:42:29(UTC)
Rank: Super forum user
johnmurray

The trouble with genuine electrode ovens is: They are excellent at keeping pies/pasties at the right temperature for lunch... At a previous workplace the oven was really good at keeping chips hot until mealtime.... Consequently, electrodes kept in them at the same time tend to have a particular odour about them as they are used...
hilary  
#7 Posted : 09 August 2017 08:48:17(UTC)
Rank: Super forum user
hilary

I do miss the mince pies that used to be heated in the industrial ovens at Christmas - god knows what we were ingesting though !!

johnmurray  
#8 Posted : 09 August 2017 11:19:25(UTC)
Rank: Super forum user
johnmurray

Originally Posted by: gt Go to Quoted Post
Thank you each. I'll pat the engineers on the back as I dispose of the fridge. Graham
I've seen lots of things converted to keep electrodes dry... Filing cabinets, with a 100W bulb at the bottom... Clothing lockers..ditto...although one did have a 1000W fan heater in.. An unconverted fridge...quite good at moisture removal, although it also had milk and yogurt stored in it! Just about anything at work will eventually have a secondary use found for it.... Another place used dissimilar-metal electrodes...Cu-Ni....one guy used to make ornate clothes hooks out of them, and polish then by putting them in a cement mixer with a shovel of sand..
chris42  
#9 Posted : 09 August 2017 11:39:36(UTC)
Rank: Super forum user
chris42

How were they heating it?

Mains power or DC and bulb off say a battery. Rods don't need to get that hot 10 to 15 degree ish above current air temp.

johnmurray  
#10 Posted : 09 August 2017 16:00:41(UTC)
Rank: Super forum user
johnmurray

Originally Posted by: chris42 Go to Quoted Post
How were they heating it? Mains power or DC and bulb off say a battery. Rods don't need to get that hot 10 to 15 degree ishabove current air temp.
That would depend upon the rod/s being used. New rods still in the manufacturers packing can be stored in any dry place. Once opened, they will absorb moisture rapidly. Ideally, they will need baking at something like 150-200+ C prior to use. If stored opened for any period of time they should (in the case of hydrogen controlled rods) be discarded. Or take your chances after baking at 300C+ for several hours. Cracked rods should be thrown out. If stored opened some rods may suffer oxidation of elements within the coating, they will be useless. When I was welding low H rods, they were opened the day before and kept in an oven overnight at 150C, then transferred to a portable "quiver" for use on-site. The quiver is a piece of kit powered from the welding lead that keeps the rods warm pre-use. Manufacturers recommendations should be followed. Many contracts will specify rods to be used on a job, as well as welding procedure/tests etc. I'll repeat this: wet low-H rods are only fit for the bin...
chris42  
#11 Posted : 09 August 2017 19:10:26(UTC)
Rank: Super forum user
chris42

Originally Posted by: johnmurray Go to Quoted Post
Originally Posted by: chris42 Go to Quoted Post
How were they heating it? Mains power or DC and bulb off say a battery. Rods don't need to get that hot 10 to 15 degree ishabove current air temp.

That would depend upon the rod/s being used. New rods still in the manufacturers packing can be stored in any dry place. Once opened, they will absorb moisture rapidly. Ideally, they will need baking at something like 150-200+ C prior to use. If stored opened for any period of time they should (in the case of hydrogen controlled rods) be discarded. Or take your chances after baking at 300C+ for several hours. Cracked rods should be thrown out. If stored opened some rods may suffer oxidation of elements within the coating, they will be useless. When I was welding low H rods, they were opened the day before and kept in an oven overnight at 150C, then transferred to a portable "quiver" for use on-site. The quiver is a piece of kit powered from the welding lead that keeps the rods warm pre-use. Manufacturers recommendations should be followed. Many contracts will specify rods to be used on a job, as well as welding procedure/tests etc. I'll repeat this: wet low-H rods are only fit for the bin...

Yes I assumed the fridge would be for storage as per the link above in #3 :-

2a. Storage of electrodes in cardboard boxes requires humidity and temperature controlled storage areas. General recommended storage conditions include: - temperature 17-27°C, relative humidity ≤60% - temperature 27-37°C, relative humidity ≤50%. - electrode boxes may be stored in layers to a maximum of 7. 2b. Plastic boxes require storage conditions suitable to cardboard boxes

Otherwise as you say a far higher temp is required when handling and it is unlikely the plastic inside the fridge would survive those temperatures.

gt  
#12 Posted : 10 August 2017 08:03:20(UTC)
Rank: Forum user
gt

Thanks everyone.  I would never have known how tricky welding rods could be.  I have learnt a lot.  I'm still getting rid of the fridge though.  There will be something suitable on the market and I'll leave our engineers to get what they need.

I didn't ask about how they managed to convert the fridge to a heater because I am not sure I would want to know and anyway I'm not sure I would fully understand.  I know enough now to make a decision.

Graham

ExDeeps  
#13 Posted : 11 August 2017 06:43:53(UTC)
Rank: Super forum user
ExDeeps

Converting a fridge to a warmer is actually a pretty simple task, provided you know what you're doing. In essence a fridge removes heat from the cabinet and dumps it at the rear - you can feal it if you put your hand at ther back of the fridge. There's a very simple "fridge cycle" at work involving relative temps and pressures and a refridgerant changing phases from a gas to a liquid. Turning the bak section around would probably do the job, you'll end up with cold air behind the cabinet and a warm interior. Why not ask them how they did it?

To be honest, I would personally commend the guys for doing a neat job, using engineering know how and skills and simply insist there are the appropriate inspections and tests (PAT etc) done as well as ensuring the refrigerant charge is OK. Why chuck something away because it's a bit Heath Robinson? All you'll do is alienate the guys,

Jim

johnmurray  
#14 Posted : 11 August 2017 07:01:45(UTC)
Rank: Super forum user
johnmurray

Because it cannot do the job. The fridge has a plastic interior, with foam insulation, and cannot reach the specified temperature the consumables manufacturer recommends, without becoming a melted blob, at best. Now: if you wanted to extract moisture from the consumables the fridge ON ITS OWN would do the job.... The times I have brought a packet of rods from stores, opened it, noted the fur coat, and then binned the packet, and got moaned at!
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