1. A retrieval system ( 100) for retrieving a well component (30), such as a
plug, from a well tubular metal structure (31) having a restriction (32) and a top
5 (33), said retrieval system comprising:
- a tool string ( 1) having a longitudinal extension ( 10) and comprising:
- a connection tool (2) configured to connect with the well component,
- a force generator (3) having a first part (4) and a second part (5) which is connectable with the connection tool and movable in relation to the first
10 part for providing the axial force in the longitudinal extension, and
- an anchoring section (6) having at least one projectable element (7) for
anchoring the tool string,
wherein the retrieval system further comprises a safety unit (8) surrounding the tool string and having at least one wall (9) and at least one abutment face (11) 15 configured to abut the restriction, said at least one projectable element abutting the wall of the safety unit in order to anchor the tool string in the safety unit.
2. A retrieval system according to claim 1, wherein the tool string is connected
with the top via a wireline (12).
20
3. A retrieval system according to claim 1 or 2, wherein the safety unit has an
inner diameter (ID5) which is larger than an outer diameter (ODT) of the tool
string.
25 4. A retrieval system according to claim 3, wherein the inner diameter of the safety unit is less than 30% larger than the outer diameter of the tool, preferably less than 20% larger than the outer diameter of the tool, more preferably less than 10% larger than the outer diameter of the tool.
30 5. A retrieval system according to any of the preceding claims, wherein the safety unit has a first unit part (14) and a second unit part (15), the first unit part has the abutment face, and the first unit part has a larger inner diameter than an inner diameter of the second part, the at least one projectable element abutting the wall of the second unit par of the safety unit.
35
6. A retrieval system according to any of claims 1-5, wherein the safety unit has a first unit part (14) and a second unit part (15), the first unit part has the

abutment face, and the first unit part has a larger outer diameter than an outer diameter of the second part, the at least one projectable element abutting the wall of the second unit part of the safety unit.
5 7. A retrieval system according to any of the preceding claims, wherein the safety unit is made of metal.
8. A retrieval system according to any of the preceding claims, wherein the
connection tool is projectable beyond the abutment face along the longitudinal
10 extension.
9. A retrieval system according to any of the preceding claims, wherein the
safety unit has a plurality of arms (17), each arm having an end face facing away
from the top and constituting the abutment face.
15
10. A retrieval system according to any of the preceding claims, wherein the
anchoring section has at least two projectable elements (7) arranged in the same
cross-sectional plane perpendicular to the longitudinal extension.
20 11. A retrieval system according to any of the preceding claims, wherein the tool string has a first end face (18) facing the top and upon which end face a force may be applied to slightly move the tool string in relation to the safety unit to release the connection tool from the well component to be able to pull the tool string out of the well without retrieving the well component.
25
12. A retrieval system according to any of the preceding claims, wherein the tool string further comprises a cleaning tool (19) configured to eject or suck fluid to clean a profile (20) in the well component.
30 13. A downhole system comprising:
- a well tubular metal structure (31) in a borehole of a well, the well tubular metal structure comprising a restriction (32) and a plug (30), and
- a retrieval system (100) according to any of the preceding claims.
35 14. A downhole well component retrieval method, comprising:
- arranging a tool string (1) of a retrieval system (100) according to any of
claims 1-12 within the safety unit (8),

- anchoring the tool string inside the safety unit by projecting the projectable element (7),
- introducing the retrieval system into the well tubular metal structure (31) until the abutment face (11) rests against the restriction (32),
5 - moving the second part (5) of the force generator (3) in relation to the first part (4) until the connection tool (2) engages the well component (30), and
- pulling the well component by retracting the second part of the force generator
for retrieving the well component.
10 15. A downhole well component retrieval method according to claim 14, comprising detecting a failure in retrieving the well component (30), and releasing the connection tool (2) by providing a hammering force at the end face (18) of the tool string (1).
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