Bevel Preparation
Bevel Preparation
(OP)
Hi,
What ideal joint preparation would be for a shell horizontal seam joint in Tanks of thickness 15mm and above-
1. Single Bevel Preparation in one shell course (Top) and other shell course without any kind of bevel preparation by keeping edges square.
or
2. Double Bevel Preparation in one shell course (Top) and other shell course without any kind of bevel preparation by keeping edges square.
Is there any standard or any kind of literature mentioning the requirements of bevel preparation or bevel preparation which changes as per the thickness & position of welding.
Thanks
What ideal joint preparation would be for a shell horizontal seam joint in Tanks of thickness 15mm and above-
1. Single Bevel Preparation in one shell course (Top) and other shell course without any kind of bevel preparation by keeping edges square.
or
2. Double Bevel Preparation in one shell course (Top) and other shell course without any kind of bevel preparation by keeping edges square.
Is there any standard or any kind of literature mentioning the requirements of bevel preparation or bevel preparation which changes as per the thickness & position of welding.
Thanks





RE: Bevel Preparation
RE: Bevel Preparation
For example API 650 contains fabrication requirements for oil storage tanks.
RE: Bevel Preparation
This is my personal preference, and has been done many times:
Your option #1 for thick <= 7/8", option # 2 for thk >7/8" if weld from inside is accessible.
This is only for field welding after equipment is stacked up.
RE: Bevel Preparation
If its Sub arc, which is likely the most productive process available for the welding of large above ground storage tanks (horizontally), then a single bevel on the upper course would be the preferred joint prep. The SAW process lends itself very well in a series of fillet welds to make the weldment. Speeds of up to 35 ipm can be realized depending on #/size of wires used.
For the verticals I would go with some form of automatic system use a Dbl Bevel with an all position FCAW. For equip, speed of production/quality, my preference would be to use a fully automatic system from ESAB called the Rail-Trac. A completely programmable (EASY to use), lightweight and highly versatile pce of automation.
yes..there is no doubt that capital cost is a consideration: ~60K for a sub arc tank welder and say ~16K for a railtrac. But your welds will be consistent, look great, go in extremely fast and your total cost of welding will be significantly less.
I've used both .. and they work great...just my .02
stk
RE: Bevel Preparation
stk
RE: Bevel Preparation
Thanks for all your valuable answers -
The welding will be performed in Fabrication yard and the welding process which we are going to use is SMAW.In this case which kind of bevel preparation would be ideal to use.
Thanks in advance for your reply.
RE: Bevel Preparation
For the situation you describe I would opt for the single bevel on the top plate. You'll also need to decide what size land, if any, and root opening, if any, would be appropriate. Whether or not you have access to the back side of the joint will influence those decisions.