Electric heating – Inductive heating – Metal working
Patent
1999-06-29
2000-06-20
Leung, Philip H.
Electric heating
Inductive heating
Metal working
219611, 219615, 219616, 219647, 228220, H05B 610, B23K 1302
Patent
active
060780312
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
The invention relates to a method and device for joining oilfield tubulars. Oilfield tubulars that are used within oil and/or gas production wells include reeled systems, coiled tubing, expandable slotted tubing (EST), expandable tubing, accessories to well tubulars and drill pipes. Oilfield tubulars that are used outside a well are offshore and onshore pipelines for the transport of crude oil and/or natural gas, risers that extend between the waterbottom and a platform deck, and tethers for mooring tension leg platforms.
During drilling and completion of an oil or gas production or fluid or heat injection well, elongate strings of well tubulars and accessories have to be inserted into the well to drill the well and protect the well against caving in and to facilitate a safe production of oil and gas through the well. The conventional way of protecting a well against caving in is to create a casing by screwing together one or more strings of casing pipes that are lowered into the well and cemented in place. Production of oil and gas takes place via one or more elongate production strings, consisting of production tubes that are interconnected by screw thread couplings, which production strings are suspended within the interior of the casing.
BACKGROUND OF THE INVENTION
Accordingly the conventional procedure for drilling and completing a well requires many hundreds of screw thread connections to be made. Making up of these connections at the drilling floor is a time consuming procedure and it requires use of carefully machined well tubulars.
A significant problem with the conventional screw thread connections is that if the wall strength at the location of the joint needs to be similar to that of the rest of the tubular the accumulated wall thickness of the pipes at the Location of the joint needs to be significantly more than that of the rest of the pipe. The presence of such bulbs at the locations of the joints and the requirement that the string of tubulars must be lowered into the well leads to the requirement of a significant spacing between the external pipe wall and the internal wall of a surrounding tubular such as a casing or the borehole wall. For conventional production tubings with male screw thread joints having a larger outer diameter than the rest of the tubing operational requirements normally require that the minimum spacing between the casing and nominal tubing size is at least 2 cm at each side of the tubing wall. This requirement leads to a significant unused annular space around the production tubing and thus to a reduced production capacity of the well or an increased well size.
It is observed that it is known in the art to use well tubulars with internally and externally flush screw thread connections. A disadvantage of these connections is that they form weak spots with a significantly lower strength than the rest of the pipe.
Safety requirements and explosion hazards at oil or gas wellheads limit the possibility of welding operations. It is known from European patent specification 396204 to safely weld well tubulars together using a friction welding technique where a ring is rotated at high speed while the tubing ends are pressed onto the ring. Disadvantages of the known friction welding technique are, however, that it is difficult to accurately control the temperature and that the ring and pipe ends will often deform which leads to irregular inner and outer surfaces at the location of the joint. The joint therefore often has to brought into a required regular shape by pulling an expansion mandrel therethrough and/or by machining away any wire edges and other irregularities.
BRIEF SUMMARY OF THE INVENTION
The present invention aims to provide a method and device for joining well and other oilfield tubulars and accessories thereof in an efficient and safe manner.
The device should be easily movable such that it can be mounted on a drilling, workover or other oilfield rig, such as a pipelaying vessel. The method should be able to be performed by drilling
REFERENCES:
patent: 2649527 (1953-08-01), Chapman et al.
patent: 2730599 (1956-01-01), Ronay
patent: 3603759 (1971-09-01), Peacock
patent: 4026583 (1977-05-01), Gottlieb
patent: 4084739 (1978-04-01), Koltz et al.
patent: 5118028 (1992-06-01), Ogawa et al.
Bliault Alan Edgar John
Cumming Francis Alexander
Laws Mark Seth
Leung Philip H.
Shell Research Limited
LandOfFree
Method and device for joining oilfield tubulars does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and device for joining oilfield tubulars, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and device for joining oilfield tubulars will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1855164