Spacer with specially fastened springs for fuel assemblies of nuclear reactors

A spacer of a fuel assembly for a light-water cooled nuclear reactor, the spacer comprising:

• webs crossing each other to form meshes for inserting fuel rods having center line directions, said webs having snap-in openings formed therein, said webs having assembly opening areas formed therein with substantially slot-shaped opening parts having ends with edges, said assembly opening areas having enlarged opening parts each leading from a respective one of said substantially slot-shaped opening parts in parts of said webs, and said webs having inner surfaces facing toward the fuel rods;
• a plurality of springs each held in one of said assembly opening areas in one of said webs, said springs having an operating position and an assembly position offset laterally relative to said operating position, and said springs having a spring force;
• each of said springs having a resilient central part facing toward a fuel rod, said central part having a top and a bottom relative to the center line direction, and said central part having end strips each extending substantially parallel to a respective one of said webs and adjoining a respective one of said top and bottom, said end strips carrying a protuberance protruding and pointing toward said resilient central part and limiting deflection of each of said springs;
• each of said end strips having two lateral rims each extending parallel to the center line direction and bent away from a fuel rod about the center line direction;
• profiled sections each seated on a respective one of said rims of said end strips, said profiled sections having inner parts respectively supported on said inner surface of a respective one of said webs in said operating position of said spring, and said profiled sections having outer parts encompassing said edges at said ends of said opening parts through said substantially slot-shaped opening parts;
• said outer parts of said profiled sections to be inserted in said enlarged opening parts of said assembly opening areas of said webs corresponding to said assembly position of said spring and displaced from said assembly position along said slot-shaped opening parts into said operating position;
• and
• at least a part of each spring carrying a protuberance pointing away from a fuel rod and engaging in said snap-in opening in said operating position of said springs with the fuel rod inserted.

A spacer of a fuel assembly for a light-water cooled nuclear reactor, the spacer comprising:

• webs crossing each other to form first and second meshes for inserting fuel rods having center lines, said webs including common webs between two of said meshes, said common webs having a first side surface facing toward a first one of the fuel rods and a second side surface facing toward a second one of the fuel rods, said common webs having assembly opening areas formed therein defining rims of said assembly openings and web edges at said rims, said assembly opening areas having an enlarged opening part at a given position on one of said webs, at least one substantially slot-shaped opening part having opening edges extending transverse to the fuel rods and end edges disposed one above the other, and said webs having snap-in openings;
• and
• first and second springs held in said assembly opening areas and having central parts, assembly positions, operating positions and spring forces;
• a) said first spring including:
• i) a first resilient central part protruding into one of said first meshes, said first resilient central part laterally supporting a first fuel rod to be inserted in said first mesh, and said first resilient central part having a top and a bottom relative to the center line of a fuel rod and two first end strips each adjoining a respective one of said top and bottom;
• ii) four rims including left and right lateral rims disposed on each of said two first end strips, said four rims extending approximately parallel to the center line of the fuel rod and bent away from the first fuel rod;
• iii) first profiled sections each disposed on a respective one of said four rims, each of said first profiled sections having an inner profiled section part supported on said first side surface of said common web in said operating position of said first spring, and an outer profiled section part encompassing said web edges through said assembly opening area;
• b) said second spring including:
• i) a second resilient central part protruding into one of said second meshes, said second resilient central part laterally supporting a second fuel rod to be inserted in said second mesh, and said second resilient central part having a top and a bottom relative to the center line of a fuel rod and two second end strips each adjoining a respective one of said top and bottom;
• ii) four rims including left and right lateral rims on each of said two second end strips, said four rims extending approximately parallel to the center line of the fuel rod and bent away from the second fuel rod;
• and
• iii) second profiled sections each disposed on a respective one of said four rims, each of said second profiled sections having an inner profiled section part supported on said second side surface of said common web in said operating position of said second spring, and an outer profiled section part encompassing said web edges through said assembly opening area;
• c) said end strips carrying a protuberance and pointing toward said resilient central part, limiting deflection of said first and said second springs, and including mutually opposite upper end strips and mutually opposite lower end strips, and one of said first and an adjacent one of said second profiled sections shaped to form four profiled section pairs, in said operating position of both of said springs;
• i) said outer profiled section parts of said first profiled sections to be inserted from said first side surface and said outer profiled section parts of said second profiled sections to be inserted from said second side surface, in said enlarged opening part in said position on said one web laterally displaced relative to said operating position of said springs;
• ii) said outer profiled section parts guided in said opening edges upon laterally displacement of said springs from said assembly position into said operating position;
• and
• iii) a pair of said profiled section pairs located one above the other and positioned on said end edges upon jointly pushing said springs laterally into said operating position;
• and
• d) one of said springs having at least one part pressed by said spring force into said snap-in opening in said operating position of both of said springs.

A spacer of a fuel assembly for a light-water cooled nuclear reactor, the spacer comprising:

• webs crossing each other to form first and second meshes for inserting fuel rods having center lines, said webs including common webs between two of said meshes, said common webs having a first side surface facing toward a first one of the fuel rods and a second side surface facing toward a second one of the fuel rods, said common webs having assembly openings formed therein defining rims of said assembly openings and web edges at said rims, said assembly opening areas having an enlarged opening part at a given position on one of said webs, at least one substantially slot-shaped opening part having opening edges extending transverse to the fuel rods and end edges disposed one above the other, and said webs having snap-in openings;
• and
• first and second springs held in said assembly openings and having central parts, assembly positions, operating positions and spring forces;
• a) said first spring including:
• i) a first resilient central part protruding into one of said first meshes, said first resilient central part laterally supporting a first fuel rod to be inserted in said first mesh, and said first resilient central part having a top and a bottom relative to the center line of a fuel rod and two first end strips each adjoining a respective one of said top and bottom;
• ii) four rims including left and right lateral rims disposed on each of said two first end strips, said four rims extending approximately parallel to the center line of the fuel rod and bent away from the first fuel rod;
• iii) first profiled sections each disposed on a respective one of said four rims, each of said first profiled sections having an inner profiled section part supported on said first side surface of said common web in said operating position of said first spring, and an outer profiled section part encompassing said web edges through said assembly opening area;
• b) said second spring including:
• i) a second resilient central part protruding into one of said second meshes, said second resilient central part laterally supporting a second fuel rod to be inserted in said second mesh, and said second resilient central part having a top and a bottom relative to the center line of a fuel rod and two second end strips each adjoining a respective one of said top and bottom;
• ii) four rims including left and right lateral rims on each of said two second end strips, said four rims extending approximately parallel to the center line of the fuel rod and bent away from the second fuel rod;
• and
• iii) second profiled sections each disposed on a respective one of said four rims, each of said second profiled sections having an inner profiled section part supported on said second side surface of said common web in said operating position of said second spring, and an outer profiled section part encompassing said web edges through said assembly opening area;
• c) said end strips carrying a protuberance and pointing toward said resilient central part, limiting deflection of said first and said second springs, and including mutually opposite upper end strips and mutually opposite lower end strips, and one of said first and an adjacent one of said second profiled sections shaped to form four profiled section pairs, in said operating position of both of said springs;
• i) said outer profiled section parts of said first profiled sections to be inserted from said first side surface and said outer profiled section parts of said second profiled sections to be inserted from said second side surface, in said enlarged opening part in said position on said one web laterally displaced relative to said operating position of said springs;
• ii) said outer profiled section parts guided in said opening edges upon laterally displacement of said springs from said assembly position into said operating position;
• and
• iii) a pair of said profiled section pairs located one above the other and positioned on said end edges upon jointly pushing said springs laterally into said operating position;
• and
• d) at least a part carrying a protuberance pointing away from a fuel rod and engaging in said snap-in opening in said operating position of both of said springs.

A spacer of a fuel assembly for a light-water cooled nuclear reactor, the spacer comprising:

• webs crossing each other to form meshes for inserting fuel rods having center line directions, said webs having snap-in openings formed therein, said webs having assembly opening areas formed therein with substantially slot-shaped opening parts having ends with edges, said assembly opening areas having enlarged opening parts each leading from a respective one of said substantially slot-shaped opening parts in parts of said webs, and said webs having inner surfaces facing toward the fuel rods;
• a plurality of springs each held in one of said assembly opening areas in one of said webs, said springs having an operating position and an assembly position offset laterally relative to said operating position, and said springs having a spring force;
• each of said springs having a resilient central part facing toward a fuel rod, said central part having a top and a bottom relative to the center line direction, and said central part having end strips each extending substantially parallel to a respective one of said webs and adjoining a respective one of said top and bottom;
• two rigid knobs disposed opposite said resilient central part;
• said end strips carrying a protruberance protruding and pointing toward said relient central part and limiting deflection of each of said springs, and each of said end strips having two lateral rims each extending parallel to the center line direction and bent away from a fuel rod about the center line direction;
• profiled sections each seated on a respective one of said rims of said end strips, said profiled sections having inner parts respectively supported on said inner surface of a respective one of said webs in said operating position of said spring, and said profiled sections having outer parts encompassing said edges at said ends of said opening parts through said substantially slot-shaped opening parts;
• said outer parts of said profiled sections to be inserted in said enlarged opening parts of said assembly opening areas of said webs corresponding to said assembly position of said spring and displaced from said assembly position along said slot-shaped opening parts into said operating position;
• and
• said springs having at least one part pressed by said spring force into said snap-in opening in said operating position of said springs with the fuel rod inserted.

A spacer of a fuel assembly for a light-water cooled nuclear reactor, the spacer comprising:

• webs crossing each other to form meshes for inserting fuel rods having center line directions, said webs having snap-in openings formed therein, said webs having assembly opening areas formed therein with substantially slot-shaped opening parts having ends with edges, said assembly opening areas having enlarged opening parts each leading from a respective one of said substantially slot-shaped opening parts in parts of said webs, and said webs having inner surfaces facing toward the fuel rods;
• a plurality of springs each held in one of said assembly opening areas in one of said webs, said springs having an operating position and an assembly position offset laterally relative to said operating position, and said springs having a spring force;
• each of said springs having a resilient central part facing toward a fuel rod, said central part having a top and a bottom relative to the center line direction, and said central part having end strips each extending substantially parallel to a respective one of said webs and adjoining a respective one of said top and bottom;
• two rigid knobs disposed opposite said resilient central part;
• said end strips carrying a protuberance protruding and pointing toward said resilient central part and limiting deflection of each of said springs, and each of said end strips having two lateral rims each extending parallel to the center line direction and bent away from a fuel rod about the center line direction;
• profiled sections each seated on a respective one of said rims of said end strips, said profiled sections having inner parts respectively supported on said inner surface of a respective one of said webs in said operating position of said spring, and said profiled sections having outer parts encompassing said edges at said ends of said opening parts through said substantially slot-shaped opening parts;
• said outer parts of said profiled sections to be inserted in said enlarged opening parts of said assembly opening areas of said webs corresponding to said assembly position of said spring and displaced from said assembly position along said slot-shaped opening parts into said operating position;
• and
• at least a part of each spring carrying a protuberance pointing away from a fuel rod and engaging in said snap-in opening in said operating position of said springs with the fuel rod inserted.

A spacer of a fuel assembly for a light-water cooled nuclear reactor, the spacer comprising:

• webs crossing each other to form first and second meshes for inserting fuel rods having center lines, said webs including common webs between two of said meshes, said common webs having a first side surface facing toward a first one of the fuel rods and a second side surface facing toward a second one of the fuel rods, said common webs having assembly opening areas formed therein defining rims of said assembly openings and web edges at said rims, said assembly opening areas having an enlarged opening part at a given position on one of said webs, at least one substantially slot-shaped opening part having opening edges extending transverse to the fuel rods and end edges disposed one above the other, and said webs having snap-in openings;
• and
• first and second springs held in said assembly opening areas and having central parts, assembly positions, operating positions and spring forces;
• a) said first spring including:
• i) a first resilient central part protruding into one of said first meshes, said first resilient central part laterally supporting a first fuel rod to be inserted in said first mesh, and said first resilient central part having a top and a bottom relative to the center line of a fuel rod and two first end strips each adjoining a respective one of said top and bottom;
• ii) four rims including left and right lateral rims disposed on each of said two first end strips, said four rims extending approximately parallel to the center line of the fuel rod and bent away from the first fuel rod;
• iii) first profiled sections each disposed on a respective one of said four rims, each of said first profiled sections having an inner profiled section part supported on said first side surface of said common web in said operating position of said first spring, and an outer profiled section part encompassing said web edges through said assembly opening area;
• b) said second spring including:
• i) a second resilient central part protruding into one of said second meshes, said second resilient central part laterally supporting a second fuel rod to be inserted in said second mesh, and said second resilient central part having a top and a bottom relative to the center line of a fuel rod and two second end strips each adjoining a respective one of said top and bottom;
• ii) four rims including left and right lateral rims on each of said two second end strips, said four rims extending approximately parallel to the center line of the fuel rod and bent away from the second fuel rod;
• and
• iii) second profiled sections each disposed on a respective one of said four rims, each of said second profiled sections having an inner profiled section part supported on said second side surface of said common web in said operating position of said second spring, and an outer profiled section part encompassing said web edges through said assembly opening area;
• c) said end strips carrying a protuberance and pointing toward said resilient central part, limiting deflection of said first and said second springs, and including mutually opposite upper end strips and mutually opposite lower end strips, and one of said first and an adjacent one of said second profiled sections shaped to form four profiled section pairs, in said operating position of both of said springs;
• i) said outer profiled section parts of said first profiled sections to be inserted from said first side surface and said outer profiled section parts of said second profiled sections to be inserted from said second side surface, in said enlarged opening part in said position on said one web laterally displaced relative to said operating position of said springs;
• ii) said outer profiled section parts guided in said opening edges upon laterally displacement of said springs from said assembly position into said operating position;
• and
• iii) a pair of said profiled section pairs located one above the other and positioned on said end edges upon jointly pushing said springs laterally into said operating position;
• d) one of said springs having at least one part pressed by said spring force into said snap-in opening in said operating position of both of said springs;
• and
• two rigid knobs disposed opposite said resilient central part.

A spacer of a fuel assembly for a light-water cooled nuclear reactor, the spacer comprising:

• webs crossing each other to form first and second meshes for inserting fuel rods having center lines, said webs including common webs between two of said meshes, said common webs having a first side surface facing toward a first one of the fuel rods and a second side surface facing toward a second one of the fuel rods, said common webs having assembly openings formed therein defining rims of said assembly openings and web edges at said rims, said assembly opening areas having an enlarged opening part at a given position on one of said webs, at least one substantially slot-shaped opening part having opening edges extending transverse to the fuel rods and end edges disposed one above the other, and said webs having snap-in openings;
• and
• first and second springs held in said assembly openings and having central parts, assembly positions, operating positions and spring forces;
• a) said first spring including:
• i) a first resilient central part protruding into one of said first meshes, said first resilient central part laterally supporting a first fuel rod to be inserted in said first mesh, and said first resilient central part having a top and a bottom relative to the center line of a fuel rod and two first end strips each adjoining a respective one of said top and bottom;
• ii) four rims including left and right lateral rims disposed on each of said two first end strips, said four rims extending approximately parallel to the center line of the fuel rod and bent away from the first fuel rod;
• iii) first profiled sections each disposed on a respective one of said four rims, each of said first profiled sections having an inner profiled section part supported on said first side surface of said common web in said operating position of said first spring, and an outer profiled section part encompassing said web edges through said assembly opening area;
• b) said second spring including:
• i) a second resilient central part protruding into one of said second meshes, said second resilient central part laterally supporting a second fuel rod to be inserted in said second mesh, and said second resilient central part having a top and a bottom relative to the center line of a fuel rod and two second end strips each adjoining a respective one of said top and bottom;
• ii) four rims including left and right lateral rims on each of said two second end strips, said four rims extending approximately parallel to the center line of the fuel rod and bent away from the second fuel rod;
• and
• iii) second profiled sections each disposed on a respective one of said four rims, each of said second profiled sections having an inner profiled section part supported on said second side surface of said common web in said operating position of said second spring, and an outer profiled section part encompassing said web edges through said assembly opening area;
• c) said end strips carrying a protuberance and pointing toward said resilient central part, limiting deflection of said first and said second springs, and including mutually opposite upper end strips and mutually opposite lower end strips, and one of said first and an adjacent one of said second profiled sections shaped to form four profiled section pairs, in said operating position of both of said springs;
• i) said outer profiled section parts of said first profiled sections to be inserted from said first side surface and said outer profiled section parts of said second profiled sections to be inserted from said second side surface, in said enlarged opening part in said position on said one web laterally displaced relative to said operating position of said springs;
• ii) said outer profiled section parts guided in said opening edges upon laterally displacement of said springs from said assembly position into said operating position;
• and
• iii) a pair of said profiled section pairs located one above the other and positioned on said end edges upon jointly pushing said springs laterally into said operating position;
• d) at least a part carrying a protuberance pointing away from a fuel rod and engaging in said snap-in opening in said operating position of both of said springs;
• and
• two rigid knobs disposed opposite said resilient central part.

A spacer of a fuel assembly for a light-water cooled nuclear reactor, the spacer comprising:

• webs crossing each other to form meshes for inserting fuel rods having center line directions, said webs having centers and snap-in openings formed therein, said webs having corners and assembly opening areas formed therein with substantially slot-shaped opening parts having ends with edges, said assembly opening areas having enlarged opening parts each leading from a respective one of said substantially slot-shaped opening parts in parts of said webs, and said webs having inner surfaces facing toward the fuel rods;
• a plurality of springs each held in one of said assembly opening areas in one of said webs, said springs having an operating position, said operating position being established in said center of one of said webs between two of said corners of one of said meshes, and an assembly position offset laterally relative to said operating position, and said springs having a spring force;
• each of said springs having a resilient central part facing toward a fuel rod, said central part having a top and a bottom relative to the center line direction, and said central part having end strips each extending substantially parallel to a respective one of said webs and adjoining a respective one of said top and bottom;
• said end strips carrying a protuberance protruding and pointing toward said resilient central part and limiting deflection of each of said springs, and each of said end strips having two lateral rims each extending parallel to the center line direction and bent away from a fuel rod about the center line direction;
• profiled sections each seated on a respective one of said rims of said end strips, said profiled sections having inner parts respectively supported on said inner surface of a respective one of said webs in said operating position of said spring, and said profiled sections having outer parts encompassing said edges at said ends of said opening parts through said substantially slot-shaped opening parts;
• said outer parts of said profiled sections to be inserted in said enlarged opening parts of said assembly opening areas of said webs corresponding to said assembly position of said spring and displaced from said assembly position along said slot-shaped opening parts into said operating position;
• and
• said springs having at least one part pressed by said spring force into said snap-in opening in said operating position of said springs with the fuel rod inserted.

A spacer of a fuel assembly for a light-water cooled nuclear reactor, the spacer comprising:

• webs crossing each other to form meshes for inserting fuel rods having corners and center line directions, said webs having centers snap-in openings formed therein, said webs having assembly opening areas formed therein with substantially slot-shaped opening parts having ends with edges, said assembly opening areas having enlarged opening parts each leading from a respective one of said substantially slot-shaped opening parts in parts of said webs, and said webs having inner surfaces facing toward the fuel rods;
• a plurality of springs each held in one of said assembly opening areas in one of said webs, said springs having an operating position and an assembly position offset laterally relative to said operating position, and said springs having a spring force, said operating position being established in said center of one of said webs between two of said corners of one of said meshes;
• each of said springs having a resilient central part facing toward a fuel rod, said central part having a top and a bottom relative to the center line direction, and said central part having end strips each extending substantially parallel to a respective one of said webs and adjoining a respective one of said top and bottom;
• said end strips carrying a protuberance protruding and pointing toward said resilient central part and limiting deflection of each of said springs, and each of said end strips having two lateral rims each extending parallel to the center line direction and bent away from a fuel rod about the center line direction;
• profiled sections each seated on a respective one of said rims of said end strips, said profiled sections having inner parts respectively supported on said inner surface of a respective one of said webs in said operating position of said spring, and said profiled sections having outer parts encompassing said edges at said ends of said opening parts through said substantially slot-shaped opening parts;
• said outer parts of said profiled sections to be inserted in said enlarged opening parts of said assembly opening areas of said webs corresponding to said assembly position of said spring and displaced from said assembly position along said slot-shaped opening parts into said operating position;
• and
• at least a part of each spring carrying a protuberance pointing away from a fuel rod and engaging in said snap-in opening in said operating position of said springs with the fuel rod inserted.

A spacer of a fuel assembly for a light-water cooled nuclear reactor, the spacer comprising:

• webs crossing each other to form first and second meshes for inserting fuel rods having center lines, said webs including centers and common webs between two of said meshes, said meshes having corners, said common webs having a first side surface facing toward a first one of the fuel rods and a second side surface facing toward a second one of the fuel rods, said common webs having assembly opening areas formed therein defining rims of said assembly openings and web edges at said rims, said assembly opening areas having an enlarged opening part at a given position on one of said webs, at least one substantially slot-shaped opening part having opening edges extending transverse to the fuel rods and end edges disposed one above the other, and said webs having snap-in openings;
• and
• first and second springs held in said assembly opening areas and having central parts, assembly positions, operating positions and spring forces, said operating position being established in said center of one of said webs between two of said corners of one of said meshes;
• a) said first spring including:
• i) a first resilient central part protruding into one of said first meshes, said first resilient central part laterally supporting a first fuel rod to be inserted in said first mesh, and said first resilient central part having a top and a bottom relative to the center line of a fuel rod and two first end strips each adjoining a respective one of said top and bottom;
• ii) four rims including left and right lateral rims disposed on each of said two first end strips, said four rims extending approximately parallel to the center line of the fuel rod and bent away from the first fuel rod;
• iii) first profiled sections each disposed on a respective one of said four rims, each of said first profiled sections having an inner profiled section part supported on said first side surface of said common web in said operating position of said first spring, and an outer profiled section part encompassing said web edges through said assembly opening area;
• b) said second spring including:
• i) a second resilient central part protruding into one of said second meshes, said second resilient central part laterally supporting a second fuel rod to be inserted in said second mesh, and said second resilient central part having a top and a bottom relative to the center line of a fuel rod and two second end strips each adjoining a respective one of said top and bottom;
• ii) four rims including left and right lateral rims on each of said two second end strips, said four rims extending approximately parallel to the center line of the fuel rod and bent away from the second fuel rod;
• and
• iii) second profiled sections each disposed on a respective one of said four rims, each of said second profiled sections having an inner profiled section part supported on said second side surface of said common web in said operating position of said second spring, and an outer profiled section part encompassing said web edges through said assembly opening area;
• c) said end strips carrying a protuberance protruding and pointing toward said resilient central part and limiting deflection of each of said springs, and including mutually opposite upper end strips and mutually opposite lower end strips, and one of said first and an adjacent one of said second profiled sections shaped to form four profiled section pairs, in said operating position of both of said springs;
• i) said outer profiled section parts of said first profiled sections to be inserted from said first side surface and said outer profiled section parts of said second profiled sections to be inserted from said second side surface, in said enlarged opening part in said position on said one web laterally displaced relative to said operating position of said springs;
• ii) said outer profiled section parts guided in said opening edges upon laterally displacement of said springs from said assembly position into said operating position;
• and
• iii) a pair of said profiled section pairs located one above the other and positioned on said end edges upon jointly pushing said springs laterally into said operating position;
• and
• d) one of said springs having at least one part pressed by said spring force into said snap-in opening in said operating position of both of said springs.

A spacer of a fuel assembly for a light-water cooled nuclear reactor, the spacer comprising:

• webs crossing each other to form first and second meshes for inserting fuel rods having center lines, said webs including common webs between two of said meshes and having centers, and said meshes having corners, said common webs having a first side surface facing toward a first one of the fuel rods and a second side surface facing toward a second one of the fuel rods, said common webs having assembly openings formed therein defining rims of said assembly openings and web edges at said rims, said assembly opening areas having an enlarged opening part at a given position on one of said webs, at least one substantially slot-shaped opening part having opening edges extending transverse to the fuel rods and end edges disposed one above the other, and said webs having snap-in openings;
• and
• first and second springs held in said assembly openings and having central parts, assembly positions, operating positions and spring forces, said operating position being established in said center of one of said webs between two of said corners of one of said meshes;
• a) said first spring including:
• i) a first resilient central part protruding into one of said first meshes, said first resilient central part laterally supporting a first fuel rod to be inserted in said first mesh, and said first resilient central part having a top and a bottom relative to the center line of a fuel rod and two first end strips each adjoining a respective one of said top and bottom;
• ii) four rims including left and right lateral rims disposed on each of said two first end strips, said four rims extending approximately parallel to the center line of the fuel rod and bent away from the first fuel rod;
• iii) first profiled sections each disposed on a respective one of said four rims, each of said first profiled sections having an inner profiled section part supported on said first side surface of said common web in said operating position of said first spring, and an outer profiled section part encompassing said web edges through said assembly opening area;
• b) said second spring including:
• i) a second resilient central part protruding into one of said second meshes, said second resilient central part laterally supporting a second fuel rod to be inserted in said second mesh, and said second resilient central part having a top and a bottom relative to the center line of a fuel rod and two second end strips each adjoining a respective one of said top and bottom;
• ii) four rims including left and right lateral rims on each of said two second end strips, said four rims extending approximately parallel to the center line of the fuel rod and bent away from the second fuel rod;
• and
• iii) second profiled sections each disposed on a respective one of said four rims, each of said second profiled sections having an inner profiled section part supported on said second side surface of said common web in said operating position of said second spring, and an outer profiled section part encompassing said web edges through said assembly opening area;
• c) said end strips carrying a protuberance protruding and pointing toward said resilient central part and limiting deflection of each of said springs, and including mutually opposite upper end strips and mutually opposite lower end strips, and one of said first and an adjacent one of said second profiled sections shaped to form four profiled section pairs, in said operating position of both of said springs;
• i) said outer profiled section parts of said first profiled sections to be inserted from said first side surface and said outer profiled section parts of said second profiled sections to be inserted from said second side surface, in said enlarged opening part in said position on said one web laterally displaced relative to said operating position of said springs;
• ii) said outer profiled section parts guided in said opening edges upon laterally displacement of said springs from said assembly position into said operating position;
• and
• iii) a pair of said profiled section pairs located one above the other and positioned on said end edges upon jointly pushing said springs laterally into said operating position;
• and
• d) at least a part carrying a protuberance pointing away from a fuel rod and engaging in said snap-in opening in said operating position of both of said springs.