Surface-controlled subsurface safety valve (SCSSV)
A downhole safety valve that is operated from surface facilities through a control line strapped to the external surface of the production tubing. Two basic types of SCSSV are common: wireline retrievable, whereby the principal safety-valve components can be run and retrieved on slickline, and tubing retrievable, in which the entire safety-valve assembly is installed with the tubing string. The control system operates in a fail-safe mode, with hydraulic control pressure used to hold open a ball or flapper assembly that will close if the control pressure is lost.
Inconel 625 is a material with excellent resistance to pitting, crevice and corrosion cracking. Highly resistant in a wide range of organic and mineral acids. Good high temperature strength.
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Chemical Composition |
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Nickel |
Chromium |
Iron |
Molybdenum |
Columbium + Tantalum |
Carbon |
Manganese |
Silicon |
Phosphorus |
Sulfur |
Aluminum |
Titanium |
Cobalt |
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% |
% |
% |
% |
% |
% |
% |
% |
% |
% |
% |
% |
% |
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min. |
max. |
max. |
max. |
max. |
max. |
max. |
max. |
max. |
max. |
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58.0 |
20.0-23.0 |
5.0 |
8.0-10.0 |
3.15-4.15 |
0.10 |
0.50 |
0.5 |
0.015 |
0.015 |
0.4 |
0.40 |
1.0 |
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Norm Equivalence |
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Grade |
UNS No |
Euro norm |
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No |
Name |
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Alloy |
ASTM/ASME |
EN10216-5 |
EN10216-5 |
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625 |
N06625 |
2.4856 |
NiCr22Mo9Nb |