DOWNHOLE RECEPTACLE FOR TRACER INSTALLATION

Abstract

A downhole receptacle for tracer installation, comprises a housing and a tracer material arranged within the housing. The tracer material is water soluble. And the housing has an outer shape that corresponds to an outer shape of a standard gas lift valve. Further a method for the installation of a downhole receptacle for a tracer includes the steps of (a) running completion with at least one side pocket mandrel with or without a pre-installed dummy gas lift valve; and (b) replacing the dummy gas lift valve with a downhole receptacle for a tracer or installing a downhole receptacle into the side pocket mandrel.

Claims

1. A downhole receptacle for tracer installation, comprising: a. a housing; b. a tracer material arranged within the housing wherein the tracer material is water soluble; and wherein c. the housing has an outer shape that corresponds to an outer shape of a standard gas lift valve.

2. The downhole receptacle according to claim 1, wherein the housing is generally cylinder shaped and has a diameter of about 1.5 inches.

3. The downhole receptacle according to claim 1, further comprising a metallic mesh or slots arranged within the upper part of the housing that hold the tracer material.

4. The downhole receptacle according to claim 1, wherein the tracer material is held by a polymer material or is inserted into the housing as particles of particular grain size.

5. The downhole receptacle according to claim 1, wherein the lower housing comprises at least one inlet opening and a set of upper slots, both connected with a flow path, and at least one top outlet opening for allowing a flow of fluid through the downhole receptacle.

6. The downhole receptacle according to claim 5, wherein the lower inlet opening is arranged at the upstream end and the upper slot openings are arranged midstream of the downhole receptacle.

7. The downhole receptacle according to claim 5, wherein at least one of the outlet openings is arranged at the cylinder wall of the downhole receptacle.

8. The downhole receptacle according to claim 1, wherein the housing comprises threads at the downstream end of the downhole receptacle for connection to a gas lift valve deployment tool.

9. The downhole receptacle according to claim 1, wherein the housing comprises a pointed end at the upstream end of the downhole receptacle.

10. The downhole receptacle according to claim 9, wherein the pointed end comprises two lower inlet openings that have an enlarged size compared to a common gas lift valve, for providing a higher flow rate through the downhole receptacle.

11. A method for the installation of a downhole receptacle for a tracer comprising the following steps of: a. running completion with at least one side pocket mandrel with or without a pre-installed dummy gas lift valve; and b. replacing the dummy gas lift valve with a downhole receptacle for a tracer or installing a downhole receptacle into the side pocket mandrel.

12. The method for the installation of a downhole receptacle according to claim 11, wherein the step of replacing the dummy gas lift valve with a downhole receptacle comprises the step of retrieving the dummy gas lift valve using a slickline and a kickover tool.

13. The method for the installation of a downhole receptacle according to claim 11, wherein the step of replacing the dummy gas lift valve with a downhole receptacle comprises the step of inserting the downhole receptacle into the side pocket mandrel by a kickover tool.

Description

3. DESCRIPTION OF THE FIGURES

[0028] In the following preferred embodiments of the invention are disclosed by means of the figures. In which shows:

[0029] FIG. 1: a side view of a preferred embodiment of a downhole receptacle device for tracer installation;

[0030] FIG. 2: a side partially sectional view of the embodiment of FIG. 1, showing the interiors of the downhole receptacle;

[0031] FIG. 3: a schematic view of the fluid flow through the embodiment of FIG. 1;

[0032] FIG. 4A: a side view of the upstream end of the embodiment of FIG. 1;

[0033] FIG. 4B a bottom view of the upstream end of the embodiment of FIG. 1;

[0034] FIG. 5A-G schematic side views of a preferred running and pulling procedure for the downhole receptacle of FIG. 1; and

[0035] FIG. 6 a flowchart for the installation process of a downhole receptacle within a new well and within an existing well.

4. DESCRIPTION OF PREFERRED EMBODIMENTS

[0036] In the following preferred embodiments of the invention are disclosed by means of the figures.

[0037] FIG. 1 shows side view of a preferred embodiment of a downhole receptacle 1 for tracer installation within a oil a producing well. The downhole receptacle 1 comprises housing 10 that contains a chemical tracer material 20. The chemical tracer material 20 is arranged within the upper part of the housing 10 and is water soluble to indicate water production of the well.

[0038] The housing 10 is preferably made of stainless steel. The seals 11 are made of Aflas or Chemraz type of materials, which are more resistant than neoprene. In H2S environments the housing could be made of inconel. It has an outer shape that corresponds to an outer shape of a standard gas lift valve or a dummy gas lift valve. Thus, the downhole receptacle can be installed instead of a dummy gas lift valve in a common side pocket mandrel 40 for a gas lift valve. The housing of the downhole receptacle 1 is generally cylinder shaped and has a diameter D of about 1 to 2 inches, preferably it has a diameter D of about 1.5 inches. The housing 10 comprises a pointed end 15 at the upstream end 2 of the downhole receptacle 1, which is adapted to be installed in a side-pocket mandrel 40 for a gas lift valve (see FIG. 5).

[0039] The downhole receptacle further comprises a metallic mesh or slots 14 arranged within the upper part of the housing 10, wherein the metallic mesh holds the chemical tracer material 20, which is preferably bound or held by a polymer material.

[0040] For allowing a fluid flow through the receptacle 1 the housing 10 comprises at least one inlet opening 12 upstream 2, a plurality of inlet openings or slots 14 midstream 4, arranged in longitudinal direction of the housing 10 and at least one outlet opening 16 downstream 3. In the shown embodiment the housing 10 has two inlet openings or noses 12 at the upstream end 2. The two inlet openings 12 at the upstream end 2 are shown in more detail in FIGS. 4A and 4B. They are preferably oval shaped and arranged on opposite sides of the pointed end 15.

[0041] The a least one of the outlet openings 16 is arranged at the cylinder wall of the downhole receptacle 1. In the shown embodiment the outlet openings 16 are preferably slot shaped and arranged also in longitudinal direction of the housing 10. The outlet openings 16 are arranged at the cylinder wall of the downhole receptacle 1 more downstream than the inlet openings 14. In addition, a further outlet opening 18 at the downstream end 3 of the downhole receptacle 1 may be provided.

[0042] FIG. 3 shows the liquid flow through the interior of the downhole receptacle 1. A part of the well's main flow 60 enters the inlet openings 12 at the upstream end 2 of the receptacle 1 as shown with arrow 62. This liquid forms partial flow 61 that flows longitudinally through the receptacle 1 and enters into the mesh holding the tracer material 20. In addition, another part of the well's main flow 60 leaves and/or enters the inlet/outlet openings 14 in the cylinder wall and also flows through the mesh holding the tracer material 20 as shown by arrows 63. These flows release a part of the tracer material 20 from the mesh that mixes with the liquid flow in the well. Part of the liquid flow leaves slots 16, of the receptacle 1 and part at the downstream end 3 through the outlet openings 18 as shown by arrows 64 and 65 and mixes with the main flow in the wellbore 60.

[0043] For running and pulling the downstream receptacle 1, the housing 10 comprises threads 13 at the downstream end 3 of the downhole receptacle 1 for connection to a gas lift valve deployment tool 50, 52. As shown in FIGS. 5A to 5G a common gas lift valve deployment tool 50 can be used to install, pull or replace a downstream receptacle 1. FIG. 5A shows the common gas lift valve deployment tool 50 with connection arm 52 in-line with the main body 54 of the tool 50. The downhole receptacle 1 is connected to the connection arm 52 via threads 13. If the deployment tool 50 is pulled upwards, as shown in FIG. 5B, the connection arm 52 pivots outwardly and moves downhole receptacle 1 outwardly, such that it can enter by its pointed end 15 into a side pocket 42 of a gas lift valve mandrel 40. Afterwards the deployment tool 50 is moved further down to fully insert the downhole receptacle 1 into the side pocket 42, as shown in FIG. 5C.

[0044] If the downhole receptacle 1 is correctly placed within the side pocket 42 it can be released from the connection arm 52. Then the gas lift valve deployment tool 50 can be pulled out of the tubing as shown in FIG. 5D leaving the downhole receptacle 1 in installed position.

[0045] The pulling of the downhole receptacle 1 can be also done by a common gas lift valve deployment tool 50. For the pulling the gas lift valve deployment tool 50 comprises a pulling arm 54 that pivots outwardly, when moving along a gas lift valve mandrel 40, as shown in FIGS. 5E and F. If the deployment tool 50 is moved downwards the pulling arm 54 moves outwardly and can connect to the threads 13 at the downstream end 3 of the receptacle 1, as shown in FIG. 5G. When the receptacle 1 is securely connected to the pulling arm 54 the deployment tool 50 can be moved upwards to pull the downhole receptacle 1.

[0046] The use of the downhole receptacle 1 enables an easy and fast installation of tracers and replacement if the tracer material is exhausted. A method for the installation of the downhole receptacle 1 in an existing well for a tracer is shown in FIG. 6 and may comprise the following steps: [0047] a. running completion with side pocket mandrels and pre-installed dummy gas lift valves (step 106); [0048] b. replacing the dummy gas lift valve with a downhole receptacle for a tracer (step 110).

[0049] Thus, preferably for an existing well, a conventional gas lift valve or a dummy gas lift valve can be easily replaced by a downhole receptacle 1 to allow tracing of water if required. The step of replacing the dummy gas lift valve with a downhole receptacle 1 comprises the step of retrieving the dummy gas lift valve by a wireline using a kickover tool. The retrieving is followed by a step of inserting the downhole receptacle 1 into the side pocket mandrel 40 by a kickover tool 50.

[0050] In case of a new well, the completion can be run already with installed downhole receptacles 1 (step 108). Thus, the downhole receptacle 1 installation is already included in the completion cost of a conventional well requiring gas lift in the future.

[0051] If the fresh downhole receptacles 1 are installed existing water in the fluid flow 60 (see FIG. 3) can be monitored (step 112). If the tracers 20 are exhausted and further monitoring of water is required, the downhole receptacles 1 can be pulled and new or re-filled downhole receptacles 1 can be run as described above.

[0052] If no further monitoring of water is necessary or if gas lift valves are required the downhole receptacle 1 for a tracer can be replaced with a gas lift valve (step 114). Then the well will be on gas lift (step 116).

[0053] The downhole receptacle 1 is preferably installed in the vertical section of the well, in the upper completion, above the packer, located inside a side-pocket mandrel 40 for a gas lift valve.

[0054] Thus, the downhole receptacle 1 according to the present invention provides a low-cost and reliable solution to trace water in a well bore. This is particularly useful in a multi-well scenario, where several strings are connected to a RDS (Remote Degassing Station).