EP0130840A2
Expired / Lapsed
EP
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Alignment pin for guide tube assembly in nuclear power plant reactor vessel
Assignee: QUADREX CORP
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Filing: 1984-07-02
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Granted: —
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Expires: 2004-07-02
Abstract
Abstract @ Guide tube alignment pins are secured to a flange at the lower end of a guide tube of a nuclear power plant reactor vessel. They extend downwardly from the flange and enter openings in an upper core plate of a guide tube assembly as the guide tube is lowered into place to align the center of the guide tube with the center of the fuel bundle or fuel element so that the cluster control rod in the guide tube can enter the fuel bundle with the least amount of drag and in the proper time. The guide tube alignment pins include guide fingers at the lower portions thereof which enter the openings in the upper core plate for positioning the center of the guide tube over the center of the associated fuel bundle or fuel element. Intermediate the ends thereof, the guide tube alignment pins are formed with a Morse taper to increase the width of the shanks at the areas subject to frequent fractures. A locking device at the top of the guide tube alignment pins, which is integrally formed with a locking cup, is crimped for securement of the upper ends of the guide tube alignment pins to the flange at the lower end of the guide tube. Guide tube alignment pins have been made of Ni-Cr-Fe alloy X-750. To reduce stress corrosion cracking of the guide tube alignment pins, the guide tube alignment pins are heat treated by solution annealing at 2000°F ± 50°F for a minimum of one hour and then cooling to ambient temperature. This procedure is followed by heating the guide tube alignment pins at 1300°F ± 50°F for approximately twenty hours and then cooling to ambient temperature.
Inventors
- 👤 Constantine N. Spalaris
- 👤 Regis Vollmer
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-24 00:24
CPC Classifications
G; G21; G21C; G21C3/00; G21C3/30; G21C3/32; G21C3/334; F; F16; F16B; F16B35/00; Y; Y02; Y02E; Y02E30/00; Y02E30/30
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
62 words
A guide tube alignment pin (30) for aligning a guide tube (17) with a fuel bundle or fuel element in a nuclear power reactor vessel comprising: (a) a guide finger (40); and (b) a shank (35) oppositely directed from said guide finger (40), said shank (35) being tapered (37) to increase in width at the area thereof having greater susceptibility to fracture.
Claim 2
Dependent Claim
62 words
A guide tube alignment pin (30) for aligning a guide tube (17) with a fuel bundle or fuel element in a nuclear power reactor vessel comprising: (a) a guide finger (40); and (b) a shank (35) oppositely directed from said guide finger (40), said shank (35) being tapered (37) to increase in width at the area thereof having greater susceptibility to fracture.
Claim 3
Dependent Claim
19 words
A guide tube alignment pin (30) as claimed in claim 1 wherein said taper (37) is a Morse taper.
Claim 4
Dependent Claim
34 words
A guide tube alignment pin (30) as claimed in claim 1 and comprising another guide finger (41) disposed in parallel spaced relation with said first mentioned guide finger (40) to form a split pin.
Claim 5
Dependent Claim
152 words
A guide tube alignment pin assembly for aligning a guide tube (17) with a fuel bundle or element of a nuclear power reactor vessel comprising: (a) a guide tube alignment pin (30) comprising a guide finger (40) and a shank (35) oppositely directed from said guide finger (40), said shank (35) being formed with a threaded section (32) spaced from said guide finger (40) and a taper section (37) between said guide finger (40) and said threaded section (32), said tapered section (37) being contoured to increase the width at the area of said shank (35) having a section at the distal end thereof suitable for crimping; (b) a first locking device (60) disposed in threaded engagement with the threaded section (32) of said shank (35); and (c) a second locking device (65) at the distal end of said shank (35) crimped to the section of said shank (35) suitable for crimping.
Claim 6
Dependent Claim
152 words
A guide tube alignment pin assembly for aligning a guide tube (17) with a fuel bundle or element of a nuclear power reactor vessel comprising: (a) a guide tube alignment pin (30) comprising a guide finger (40) and a shank (35) oppositely directed from said guide finger (40), said shank (35) being formed with a threaded section (32) spaced from said guide finger (40) and a taper section (37) between said guide finger (40) and said threaded section (32), said tapered section (37) being contoured to increase the width at the area of said shank (35) having a section at the distal end thereof suitable for crimping; (b) a first locking device (60) disposed in threaded engagement with the threaded section (32) of said shank (35); and (c) a second locking device (65) at the distal end of said shank (35) crimped to the section of said shank (35) suitable for crimping.
Claim 7
Dependent Claim
40 words
A guide tube alignment pin assembly as claimed in claim 4 wherein said guide tube alignment pin (30) comprises another guide finger (41) disposed in parallel spaced relation with said first mentioned guide finger (40) to form a split pin.
Claim 8
Dependent Claim
154 words
A guide tube alignment pin assembly as claimed in claim 4 and comprising a flange (18) at the lower section of a guide tube (17) disposed perpendicular to the axis of said guide tube alignment pin (30), said flange (18) having a cylindrical opening formed therein providing oppositely directed annular shoulders and a reduced diameter opening between said oppositely directed annular shoulders, said first locking device (65) being formed with an annular flange (62) seated on one of said annular shoulders, said guide tube alignment pin (30) being formed with a base (36) between said shank (35) and said guide fingers (41 and 41), said base (36) having an annular flange abutting against the other of said shoulders, said fingers (40 and 41) projecting downwardly and freely from said flange (18), said tapered section (37) of said shank (35) being disposed in said reduced diameter opening of said opening formed in said flange (18).
Claim 9
Dependent Claim
50 words
A guide tube alignment pin assembly as claimed in claim 6 wherein said base (36) is nested in said cylindrical opening of said flange (18) and said tapered section (37) of said shank (35) is nested in said reduced diameter opening of said cylindrical opening formed in said flange (18).
Claim 10
Dependent Claim
103 words
A guide tube alignment pin (30) for aligning a guide tube (17) with a fuel bundle or fuel element in a nuclear power reactor vessel comprising: (a) a guide finger (40) made of a nickel base alloy; (b) a shank (35) made of a nickel base alloy oppositely directed from said guide finger (40), said shank (35) being tapered (37) to increase in width at the area thereof having greater susceptiblity to fracture; (c) said guide finger (40) and said shank (35) being heat treated to produce continuous or semi- continuous carbides at the grain boundaries of said guide tube alignment pin (30).
Claim 11
Dependent Claim
103 words
A guide tube alignment pin (30) for aligning a guide tube (17) with a fuel bundle or fuel element in a nuclear power reactor vessel comprising: (a) a guide finger (40) made of a nickel base alloy; (b) a shank (35) made of a nickel base alloy oppositely directed from said guide finger (40), said shank (35) being tapered (37) to increase in width at the area thereof having greater susceptiblity to fracture; (c) said guide finger (40) and said shank (35) being heat treated to produce continuous or semi- continuous carbides at the grain boundaries of said guide tube alignment pin (30).
Claim 12
Dependent Claim
19 words
A guide tube alignment pin (30) as claimed in claim 8 wherein said taper (37) is a Morse taper.
Claim 13
Dependent Claim
65 words
A guide tube alignment pin (30) as claimed in claim 8 and comprising another guide finger (41) made of a nickel base alloy disposed in parallel spaced relation with said first mentioned guide finger (40) to form a split pin, said other guide finger (41) being heat treated to produce continuous or semi-continuous carbides at the grain boundaries of said guide tube alignment pin (30).
Claim 14
Dependent Claim
64 words
A guide tube alignment pin (30) as claimed in claim 9 and comprising another guide finger (41) made of a nickel base alloy disposed in parallel relation with said first mentioned guide finger (40) to form a split pin, said other guide finger (41) being heat treated to produce continuous or semi-continuous carbides at the grain boundaries of said guide tube alignment pin (30).
Claim 15
Dependent Claim
99 words
A guide tube alignment pin (30) for aligning a guide tube (17) with a fuel bundle or a fuel element in a nuclear power reactor vessel comprising: (a) a guide finger (40) made of Ni-Cr-Fe; and (b) a shank (35) made of Ni-Cr-Fe and oppositely directed from said guide finger (40), said shank (35) being tapered (37) to increase in width at the area thereof having greater susceptibility to fracture, (c) said guide finger (40) and said shank (35) being heat treated by annealing at 2000°F + 50°F for at least one hour and then cooled to ambient temperature.
Claim 16
Dependent Claim
99 words
A guide tube alignment pin (30) for aligning a guide tube (17) with a fuel bundle or a fuel element in a nuclear power reactor vessel comprising: (a) a guide finger (40) made of Ni-Cr-Fe; and (b) a shank (35) made of Ni-Cr-Fe and oppositely directed from said guide finger (40), said shank (35) being tapered (37) to increase in width at the area thereof having greater susceptibility to fracture, (c) said guide finger (40) and said shank (35) being heat treated by annealing at 2000°F + 50°F for at least one hour and then cooled to ambient temperature.
Claim 17
Dependent Claim
17 words
A guide tube alignment pin (30) as claimed in claim 10 wherein said annealing is solution annealing.
Claim 18
Dependent Claim
174 words
A guide tube alignment pin assembly for aligning a guide tube (17) with a fuel bundle or element of a nuclear power reactor vessel comprising: (a) a guide tube alignment pin (30) made of a nickel base alloy comprising a guide finger (40) and a shank (35) oppositely directed from said guide finger (40), said shank (35) being formed with a threaded section (32) spaced from said guide finger (40) and a taper section (37) between said guide finger (40) and said threaded section (32), said tapered section (37) being contoured to increase the width at the area of said shank having a section at the distal end thereof suitable for crimping; (b) a first locking device (60) disposed in threaded engagement with the threaded section (32) of said shank (35); and (c) a second locking device (65) at the distal end of said shank (35) suitable for crimping, (d) said guide tube alignment pin (30) being heat treated at 2000°F + 50°F for at least one hour and then cooled to ambient temperature.
Claim 19
Dependent Claim
174 words
A guide tube alignment pin assembly for aligning a guide tube (17) with a fuel bundle or element of a nuclear power reactor vessel comprising: (a) a guide tube alignment pin (30) made of a nickel base alloy comprising a guide finger (40) and a shank (35) oppositely directed from said guide finger (40), said shank (35) being formed with a threaded section (32) spaced from said guide finger (40) and a taper section (37) between said guide finger (40) and said threaded section (32), said tapered section (37) being contoured to increase the width at the area of said shank having a section at the distal end thereof suitable for crimping; (b) a first locking device (60) disposed in threaded engagement with the threaded section (32) of said shank (35); and (c) a second locking device (65) at the distal end of said shank (35) suitable for crimping, (d) said guide tube alignment pin (30) being heat treated at 2000°F + 50°F for at least one hour and then cooled to ambient temperature.
Claim 20
Independent Claim
81 words
A method of producing a guide tube alignment pin (30) for aligning a guide tube (17) with a fuel bundle or a fuel element in a nuclear power reactor vessel in which the guide tube alignment comprises a guide finger (40) and a shank (35) oppositely directed from the guide finger (40) comprising the steps of: (a) forming Ni-Cr-Fe into an ingot; (b) machining the ingot of Ni-Cr-Fe into said guide tube alignment pin (30); and (c) heat treating said Ni-Cr-Fe.
Claim 21
Independent Claim
81 words
A method of producing a guide tube alignment pin (30) for aligning a guide tube (17) with a fuel bundle or a fuel element in a nuclear power reactor vessel in which the guide tube alignment comprises a guide finger (40) and a shank (35) oppositely directed from the guide finger (40) comprising the steps of: (a) forming Ni-Cr-Fe into an ingot; (b) machining the ingot of Ni-Cr-Fe into said guide tube alignment pin (30); and (c) heat treating said Ni-Cr-Fe.
Claim 22
Dependent Claim
20 words
A method as claimed in claim 15 wherein said heat treatment produces continuous or semi-continuous carbides at the grain boundaries.
Claim 23
Dependent Claim
35 words
A method as claimed in claim 15 wherein said heat treatment comprises the step of annealing said Ni-Cr-Fe at 2000°F + 50°F for a minimum of one hour, and cooling said Ni-Cr-Fe to ambient temperature.
Claim 24
Dependent Claim
22 words
A method as claimed in claim 15 wherein said heat treating of said Ni-Cr-Fe is performed after the machining of said Ni-Cr-Fe.
Claim 25
Dependent Claim
22 words
A method as claimed in claim 13 wherein said ingot of Ni-Cr-Fe is reduced in cross-section before the machining of said Ni-Cr-Fe.
References Cited (Backward Citations)
No citation records indexed.
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