welders...i need some help!!

[Kenmore]

Im trying to develop a weld procedure at work to weld cement lined pipe. Anyone have any tips and tricks as to cutting it? Gap? gasket width? Land? Electrode?

[Northwinds]

send MB1 a pm

[justletmehunt]

I had to weld it once many moons ago on the pipeline. If I remember correctly, each joint had what looked like a bell on the end of it. Asbestos gasket went in between (pretty much giving you your gap).
Root was 6010 downhand
Hot Pass and Cap - 7010 downhand.
The only thing I had to do differently was leave a weep hole at the top until the rest of the joint was welded and then go back and close it up with root, hp and cap.

Again, that was over 12 years ago so I'm sure there are others that will have a better procedure.

[pyk]

Originally Posted by justletmehunt

I had to weld it once many moons ago on the pipeline. If I remember correctly, each joint had what looked like a bell on the end of it. Asbestos gasket went in between (pretty much giving you your gap).
Root was 6010 downhand
Hot Pass and Cap - 7010 downhand.
The only thing I had to do differently was leave a weep hole at the top until the rest of the joint was welded and then go back and close it up with root, hp and cap.

Again, that was over 12 years ago so I'm sure there are others that will have a better procedure.

I welded on 2 kinds back in the good old days. One was a bell and spigot type as you describe. The other was like regular pipe with a gasket spacer . The problem was trying to cut the pipe without damaging/chipping the cement liner. A full penetration weld required without burning out the gasket. I did a lot of swearing at the guys with the xray truck. I didn't know cement lined pipe was still being used.

[Kenmore]

Thanks for the replies thus far fellas. So far i have tried a 1/8 gasket...but it is tough to not get to much pen. Welding that gap cold is causing alot of grief. I tried with 1/16 gasket today. Could run much hotter with minimal pen. I also tried the RMD setting on the mig and it really went well. Will see what the X-ray truck says tommorow. Still have not found a great tool to cut it. I got a blade thats for cutting titanium that seems to be holding up the best and not chipping badly...but it is 20 minutes to cut thru a 4" pipe. In this day and age...i cant for the life of me figure out why they are using this. I would think there would be a better option for material.

[Boogerfart]

What application are they using it for? I haven't heard anyone even talk about cement lined pipe in years...

[Kenmore]

Originally Posted by Boogerfart

What application are they using it for? I haven't heard anyone even talk about cement lined pipe in years...

I believe it will be used in a potash mine transferring some highly abrasive media.

[bloopbloob]

Originally Posted by Kenmore

I believe it will be used in a potash mine transferring some highly abrasive media.

Haha it's a long shot, but try getting the pipe changed? I've done some high abrasive piping, they used ceramic wear-back elbows on any directional changes. Around 9 on the mohs hardness scale iirc. Straight sections were just heavy wall pipe. Also AR400 steel deflector plates at the exit

[^v^Tinda wolf^v^]

It’s all been explained very well. My personal preference is 1/8 land and 1/8 gap for most butt joints and set your voltage accordingly for the rod specified. If your procedure allows you to do so I would recommend removing the mill scale on the inside of the pipe ever so slightly. It’s amazing what this simple little trick does for your root. It promotes even build up and depending on what position you are in, for example the flat position you can build your root to suit the specification and it will just keep building and building into a huge grape without dropping your key hole out. Hope that helps.

Several years ago I estimated how many kilometres of weld I’ve done givin the amount of vessels I’ve welded. It was around 89klm😁

Kick the tires and light the fires big daddy!

[nick0danger]

Potash is very corrosive, any electrical work i do for potash is SS, or it has to be coated in plastic. I am going out on a limb i assume cement lined is way cheaper than SS.

[kessoim]

You can check a few youtube videos. If you are lucky then you might find some good video about this. I successfully completed my first welding work watching only youtube videos.

[bloopbloob]

Originally Posted by bloopbloob

Haha it's a long shot, but try getting the pipe changed? I've done some high abrasive piping, they used ceramic wear-back elbows on any directional changes. Around 9 on the mohs hardness scale iirc. Straight sections were just heavy wall pipe. Also AR400 steel deflector plates at the exit

Just to clarify, pipe is still steel... joints are still welded normally. But any radius has a straight section before the next radius, without the ceramic coating. This lets you weld it like regular pipe, and true high wear areas have excellent wear resistance. Pricey though. I think the 90* 8" elbows were around $1400 a pop...

[Gammaboy]

Originally Posted by Kenmore

Thanks for the replies thus far fellas. So far i have tried a 1/8 gasket...but it is tough to not get to much pen. Welding that gap cold is causing alot of grief. I tried with 1/16 gasket today. Could run much hotter with minimal pen. I also tried the RMD setting on the mig and it really went well. Will see what the X-ray truck says tommorow. Still have not found a great tool to cut it. I got a blade thats for cutting titanium that seems to be holding up the best and not chipping badly...but it is 20 minutes to cut thru a 4" pipe. In this day and age...i cant for the life of me figure out why they are using this. I would think there would be a better option for material.

I failed a guy last winter that would have been awesome for this job. Didn't need a gasket or anything... But seriously would like to see the code for this. Good luck (and remember. The Xray hand only takes the picture, it's not his fault the kid is ugly)

[Kenmore]

Originally Posted by ^v^Tinda wolf^v^

It’s all been explained very well. My personal preference is 1/8 land and 1/8 gap for most butt joints and set your voltage accordingly for the rod specified. If your procedure allows you to do so I would recommend removing the mill scale on the inside of the pipe ever so slightly. It’s amazing what this simple little trick does for your root. It promotes even build up and depending on what position you are in, for example the flat position you can build your root to suit the specification and it will just keep building and building into a huge grape without dropping your key hole out. Hope that helps.

Several years ago I estimated how many kilometres of weld I’ve done givin the amount of vessels I’ve welded. It was around 89klm😁

Kick the tires and light the fires big daddy!

Haha...millscale is the least of my worries...the cement comes out flush with the end of the pipe!! Cant have 100% pen welds. 85% max. There seems to be no real code it is shot to...all up to x-ray interpretation from what i can gather.