Any weld that cannot be completed by the front end crew on a pipeline is a tie-in weld. These welds are typically in a trench or awkward area and left for the tie-in crew to complete. The challenges of tie-ins can pose many obstacles resulting in a very manual lengthy process. The Fine Grind Cut to Clamp System provides improved productivity and safety resulting in reduced costs.
Using the FINE GRIND TOOLS from CUT TO CLAMP
cut the pipe with oxy–fuel or plasma
2. Clean Back
Once the pipe is cut for a tie-in the welder removes the exterior coating back far enough not to interfere with the weld. Traditionally a burn back would be done using a torch and oxyacetylene.
The Fine Grind Tool is a multiuse tool not only prepping the face of the pipe but also sanding back the coating 6”. This eliminates a delay where the sandblasting crew needs to come and clear the coating back before UT to can scan the weld.
When pipe is cut manually in the ditch the welder will do their best to make the face of the pipe ends as true as possible with the tools they have. This work is manual and can result in variable welding gaps and misalignment. Grinders are typically used to grind off high spots, slag or other imperfections. This can be a very lengthy process until by eyeball the prep looks flat.
The Fine Grind Tool preps the pipe face ends from a flame cut to a precise milled V or J prep bevel for welding. Centrally supported the milling head tracks and trues the pipe face creating a factory like end. The platform for the welder is now similar to a mainline pipe joint, with consistent space for welding without large to small gaps. The tie-in becomes faster with reduced chance of repair thus increasing the quality of the weld.Hand portable tool with the ability to access any location.
4. Magnetism Check
After the pipe ends are prepped the pipe needs to be checked for unwanted magnetism that could cause arch blow while welding.
The Fine Grind Demag Band neutralizes magnetic fields which may be present in the weld preparation region of mating steel components. The demag band undertakes degaussing of the end of the pipe only. This down cycling process is relatively quick – typically less than 3 minutes. Easy operation and hand portable.
use of tradition clamps for fit up
Once pipe is prepped and in the alignment clamps a spacing tool is required to maintain the gap for welding. Traditionally a spacing wedge and hammer is used to try to maintain the gap. Hammering a wedge to space the pipe causes damage to the bevel and the possibility of internal mushrooming, increasing the chance of repairs. The new patented Cone Spacing Tool spaces the pipe undamaged. The spacing cone evenly distributes the pressure between the clamps and over the pipe bevel by use of a threaded cone insert. The gap is stabilized without damage to the root weld area. Safety is increased eliminating the use of a hammer. Easy install adjustment and removal producing an undamaged bevel for higher weld quality.