Spacer sub
The present invention involves a method and apparatus for communicating from within a wellbore to the surface of the wellbore, as well as communicating from the surface of the wellbore to downhole within the wellbore. More specifically, the present invention involves a method and apparatus for protecting and controlling cables or lines which connect surface equipment to downhole equipment. A spacer sub comprising a tubular body with a helical groove therearound is used to house one or more downhole cables. In one aspect, the spacer sub has a recess within the helical groove for housing one or more cable connectors. In another aspect, multiple helical grooves are disposed around the spacer sub to protect and house cables of different length.
1. A downhole spacer sub connectible to a working string, the sub comprising:
a tubular body having a wall defining an inner surface and outer surface,
a helical groove disposed around the outer surface of the wall, wherein the helical groove is designed to receive at least one cable, and
at least one retaining member along the helical groove, wherein the at least one retaining member secures the at least one cable within the helical groove, wherein the at least one retaining member defines a keeper plate that is countersunk within the helical groove.
2. The spacer sub of claim 1 , wherein the at least one retaining member is secured within the helical groove by one or more screws.
3. The spacer sub of claim 1 , wherein multiple retaining members are disposed along the helical groove at intervals.
4. The spacer sub of claim 1 , wherein the helical groove is dimensioned to receive more than one cable.
5. A downhole spacer sub connectible to a working string, the sub comprising:
a tubular body comprising a wall having an inner surface and outer surface,
at least two grooves disposed within the outer surface of the wall and helically around the tubular body, wherein each of the grooves is designed to receive at least one cable, and wherein each of the grooves is dimensioned to receive a cable of different length.
6. The spacer sub of claim 5 , further comprising at least one entry point for the at least one cable disposed at the bottom of each of the grooves.
7. The spacer sub of claim 5 , further comprising an entry point for the at least one cable disposed at the bottom of the spacer sub, wherein the grooves branch from the entry point for receiving more than one cable.
8. The spacer sub of claim 5 , wherein each groove is disposed within the outer surface of the wall to form a different path helically around the tubular body.
9. An apparatus for communicating information between a surface of a wellbore and within the wellbore, comprising:
a monitoring device disposed within the wellbore;
a processing device located at the surface of the wellbore;
a cable connecting the monitoring device and the processing device; and
a tubular body which absorbs a length of the cable within a helical groove disposed around the tubular body, wherein keeper plates spaced intermittently along the helical groove retain a length of the cable within the helical groove.
10. The apparatus of claim 9 , wherein the helical groove is further recessed at intervals to substantially house a connecting device within the tubular body.