Temporary support for electric submersible pump assembly
The need to have the housing of an ESP suspended by the discharge flange to allow room for downhole thermal expansion in a situation where there is no surface access to the lower end of the ESP when the discharge flange is bolted up is addressed by building the ESP on a support that is removable downhole without intervention. A controlled electrolytic material or CEM can be used or other materials that meet the structural support requirement for the ESP and then after a predetermined time lose their capacity to support leaving the ESP suspended by its discharge flange and capable of growing under thermal loading.
1. An assembly method for at least one electric submersible pump (ESP) disposed adjacent a tubular string for use in a subterranean location, comprising:
attaching at least one support to outside the string at a surface location;
building said string while building said at least one ESP on said at least one outside support at the surface location;
finishing building said ESP at the surface location with said outside support located in a borehole;
securing said ESP to the string at an upper end thereof outside the borehole;
continuing to build said string for positioning said ESP at a predetermined subterranean location;
undermining said outside support after said positioning to allow room for said ESP to respond to thermal loads when fully delivered into the borehole.
2. The method of claim 1 , comprising:
using a y-connector for said securing said ESP to said string.
3. The method of claim 2 , comprising:
bringing said y-connector to a discharge connection on said ESP with a telescoping connection.
4. The method of claim 3 , comprising:
locking said telescoping connection after securing the ESP to the y-connector.
5. The method of claim 1 , comprising:
using a controlled electrolytic material as at least a part of said outside support;
exposing said material to well conditions to undermine said material from supporting the weight of said ESP.
6. The method of claim 1 , comprising:
undermining said support by melting said support with heat.
7. The method of claim 6 , comprising:
providing a source of heat within said support.
8. The method of claim 1 , comprising:
using a shape memory alloy for at least a part of said outside support;
bringing said alloy beyond its critical temperature in the borehole;
changing the shape of said alloy so that said ESP is no longer supported by said outside support.
9. The method of claim 1 , comprising:
assembling said ESP to a length of at least 100 meters.
10. The method of claim 1 , comprising:
providing a plurality of axially spaced ESPs with each supported from a discrete outside support.
11. The method of claim 1 , comprising:
undermining said outside support with a chemical reaction.
12. The method of claim 11 , comprising:
adding at least one reactant to the borehole for said undermining.
13. The method of claim 11 , comprising:
selectively containing at least one reactant in said outside support;
undermining said outside support by release of said reactant.
14. The method of claim 1 , comprising:
triggering said undermining on an elapsed time basis.