JP2000303605A - Steel bundle and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a steel bundle which does not cause dew condensation and allows to visually observe the fitting depth of a threaded bar and manufacturing method therefor. SOLUTION: This steel bundle 10 comprises a bundle height adjusting fittings 10, an upper threaded bar 20, a lower threaded bar 30, a sleeper fittings 40, and a supporting plate 50. The bundle height adjusting fittings 10 has a frame shape and comprises an upper portion 11 having a threaded hole 14, a lower portion 12 having a threaded hole 15, and two parallel intermediate portion 13 extending between the upper portion 11 and the lower portion 12. The bundle height adjusting fittings 10 is produced by heating a law material for bar and splitting and widening the heated bar from the split line in the middle portion.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a steel bundle and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, wooden bundles have been used for floor bundles that have been subjected to large-scale pulling. However, in order to prevent floor noise caused by deformation due to drying of the wood, the bundle has a bundle height adjusting function. In addition, steel bundles have been used to prevent termite damage. As a specific example of a conventional steel bundle, Japanese Patent Application Laid-Open
-82159, a steel bundle disclosed in Japanese Utility Model Laid-Open No. 6-185.
No. 31 discloses a steel bundle and the like. JP-A-10-82
No. 159 discloses a steel bundle in which two bent portions are formed on the upper and lower portions of a flat adjustment metal fitting so as to be displaced in the longitudinal direction, and the inner peripheral surface thereof is threaded to form two bent portions. One of the screw at the bent portion and the screw at the two lower bent portions is left-handed and the other is right-handed. The upper screw is screwed to the upper screw, and the lower screw is screwed to the lower screw. .
Further, the steel bundle disclosed in Japanese Utility Model Laid-Open No. 6-18531 has an upper threaded rod and a lower threaded rod which are threaded into a pipe-shaped adjusting bracket having a left-hand thread on one of the upper and lower parts of the pipe and a right-hand thread on the other. It is a combination.

[0003]

The conventional steel bundle has the following problems. The steel bundle disclosed in Japanese Patent Application Laid-Open No. H10-82159 has a structure in which a screw is provided only on a half circumference and the remaining half circumference is open. Therefore, when a compressive load is applied to the steel bundle,
The thread is susceptible to stress that tends to move away from the threaded rod,
Problems such as deformation of the screw portion, separation of the screw from the screw rod, and the like occur. In the steel bundle disclosed in Japanese Utility Model Laid-Open No. 6-18531, since the adjusting bracket is a pipe, the fitting depth of the threaded rod cannot be visually checked, and there is a possibility that dew condensation or rust may occur inside. SUMMARY OF THE INVENTION An object of the present invention is to provide a steel bundle and a method for manufacturing the same, in which the thread portion has sufficient strength, the fitting depth of the threaded rod is visible, and there is no risk of dew condensation or rust inside.

[0004]

The present invention to achieve the above object is as follows. (1) An upper portion having a hole penetrating in the axial direction and having one of a right-handed screw and a left-handed screw threaded on the inner periphery of the hole, and a right-handed screw having a hole penetrating in the axial direction on the inner periphery of the hole. A frame-shaped bundle height adjusting bracket comprising: a lower part in which one of the other of a left-hand thread and a left-hand thread is cut; and two parallel middle parts extending in the longitudinal direction between the upper part and the lower part. An upper screw rod which is threaded on at least a part of the outer periphery in a direction and which can be screwed to a screw on the upper part of the bundle height adjusting bracket, and which is screwed into a hole on the upper part of the bundle height adjusting bracket; And a lower screw rod which is threaded on at least a part of the outer circumference in the direction and which can be screwed to a screw at a lower portion of the bundle height adjusting bracket, and which is screwed into a hole at a lower portion of the bundle height adjusting bracket. Have steel bundles. (2) The frame-shaped bundle height adjusting bracket is formed by heating a material rod and then splitting a middle portion in the longitudinal direction of the rod horizontally and horizontally along an axis to form the bundle. Steel bundle. (3) The steel bundle according to (1), wherein a vertical rib extending in an axial direction and a horizontal rib extending in a direction orthogonal to the longitudinal rib are formed on an outer surface of the bundle height adjusting bracket. (4) The steel bundle according to (1), wherein a large receiving bracket is fixed to an upper portion of the upper screw bar, and a support plate is fixed to a lower portion of the lower screw bar. (5) The steel bundle according to (4), wherein a double-sided tape is attached to an upper surface of the large receiving metal fitting. (6) The intermediate portion has a connecting portion formed by combining two longitudinally extending portions curved in a direction approaching each other in the middle of the longitudinal direction to form a single connecting portion. Steel bundle. (7) A frame-shaped bundle height adjusting bracket having an upper portion having a screw hole, a lower portion having a screw hole, and two intermediate portions extending between the upper portion and the lower portion is manufactured, and then at least a part in a longitudinal direction. An upper threaded rod threaded around the outer periphery of the bundle height adjusting bracket with a screw that can be screwed into the upper thread of the bundle height adjusting bracket is screwed into a hole on the upper portion of the bundle height adjusting bracket, and at least a part in the longitudinal direction. A lower threaded rod threaded around the outer periphery of the bundle height adjusting bracket with a screw that can be screwed into a lower thread of the bundle height adjusting bracket is screwed into a lower hole of the bundle height adjusting bracket. The bundle height adjusting bracket cuts the bar material into a material bar having a predetermined length, heats the material bar, and pushes a middle portion of the heated material bar in the longitudinal direction along the axis. By spreading the upper and lower parts and two parallel middle parts extending longitudinally between the upper and lower parts A frame-shaped body is formed, and the upper and lower parts of the frame-shaped body are upset and forged and formed into a head of a predetermined shape, and a hole is formed in the upper part of the frame-shaped body so as to penetrate in the axial direction. While cutting either the right-hand thread or the left-hand thread, making a hole penetrating in the axial direction in the lower part of the frame-like body, cutting either the right-hand thread or the left-hand thread on the inner periphery of the hole, and bundling A height adjusting bracket is produced, and an upper screw rod, which is threaded on at least a part of the outer periphery in the longitudinal direction and which can be screwed to a screw on an upper portion of the bundle height adjusting bracket, is mounted on the upper portion of the bundle height adjusting bracket. The lower threaded rod which is screwed into the hole of the bundle height adjustment bracket and has a thread which can be screwed into the lower screw of the bundle height adjustment bracket on at least a part of the outer periphery in the longitudinal direction is attached to the lower part of the bundle height adjustment bracket. A method of manufacturing a steel bundle, which is manufactured by a process, which is screwed into a hole of a steel bundle. (8) The steel bundle according to (7), wherein a vertical rib extending in an axial direction and a horizontal rib extending in a direction perpendicular to the vertical rib are formed on an outer surface of the material rod. (9) The method for producing a steel bundle according to (7), wherein a plating step of plating the outer surface of the frame is inserted between the head forming step and the drilling of the upper and lower portions of the frame. . (10) The method for producing a steel bundle according to (7), wherein a plating step of plating an outer surface of the frame is inserted after the upper and lower screwing steps of the frame.

In the method for producing a steel bundle described in (1) to (6) and the method for producing a steel bundle described in (7) to (10), since the bundle height adjusting bracket has a frame shape, the upper threaded rod and the lower A threaded rod extends into the space between the two longitudinal extensions in the middle of the bundle height adjustment fitting to allow visual inspection of the insertion depth of the upper and lower threaded rods. In addition, the upper and lower screws of the bundle height adjustment bracket are drilled and cut on the inner circumference, so the screws are all over the circumference, the strength of the thread is large, the thread is deformed, Never leave. In the method for manufacturing a steel bundle according to the above (2) and the method for manufacturing a steel bundle according to the above (7), the frame-shaped bundle height adjusting bracket heats the material rod and then moves the intermediate portion in the longitudinal direction of the rod along the axis. Since it is formed by splitting it to the left and right, the yield is good, the cost is low, and the productivity is excellent, as compared with a steel material pressing method or shaving. In the method for manufacturing a steel bundle according to the above (3) and the method for manufacturing a steel bundle according to the above (8), since the vertical ribs extending in the axial direction are formed on the outer surface of the bundle height adjusting bracket, the bundle height adjusting bracket is not used. The operability when adjusting the bundle height by rotating it around the shaft center is good, and a dedicated tool is not required, and the strength is improved (about 14% improvement).

[0006]

1 and 2 show a steel bundle of an embodiment of the present invention, FIG. 3 shows a steel bundle of another embodiment of the present invention, and FIG. 4 shows a steel bundle of the embodiment of the present invention. The method for producing a steel bundle is shown.
In FIG. 1, the solid line indicates a state in which the bundle height adjusting bracket is contracted, and the two-dot chain line indicates a state in which the bundle height adjusting bracket is extended. Parts that are common or similar throughout all embodiments of the present invention are given the same reference numerals throughout all embodiments of the present invention.

First, a steel bundle according to an embodiment of the present invention will be described with reference to FIGS. 1, 2 and 3. Steel bundle 1 of the embodiment of the present invention
Has a bundle height adjusting metal fitting 10, an upper screw rod 20, and a lower screw rod 30. The steel bundle 1 according to the embodiment of the present invention further includes:
Large undertaking 40, support plate 50, lock nut 6
0 and 61 and a spring washer 70 may be provided.

[0008] The bundle height adjusting bracket 10 is frame-shaped. The bundle height adjusting bracket 10 has an upper portion 11 having a hole penetrating in the axial direction and having one of right-hand and left-hand screws 14 cut in the inner periphery of the hole, and a hole penetrating in the axial direction. The lower part 12 in which either the right-hand thread or the left-hand thread 15 is cut on the inner circumference of the hole.
And an intermediate portion 13 having two parallel longitudinally extending portions 13a extending in the longitudinal direction between the upper portion 11 and the lower portion 12,
Have. The cross section of the longitudinal extension 13a is substantially semicircular.

Two longitudinally extending portions 13a of the intermediate portion 13
Is larger than the outer diameter of the upper and lower screw rods 20 and 30,
In the space between the two longitudinal extensions 13a,
The upper and lower threaded rods 20 and 30 passing through the first and lower portions 12 can extend without interfering with the intermediate portion 13. Upper part 1 of bundle height adjusting bracket 10
1 and the lower portion 12, when viewed from the front, the upper side (the side farther from the intermediate portion 13) has almost the same size as the diameter of the material rod, and the lower side (the side closer to the intermediate portion 13) is larger than the diameter of the material rod. The upper side (the side farther from the intermediate portion 13) and the lower side (the side closer to the intermediate portion 13) are substantially rectangular or the lower side (the intermediate portion) having substantially the same size as the diameter of the material rod in side view. 13 is a trapezoid larger than the upper side (the side farther from the middle portion 13). The axis of the upper part 11 of the bundle height adjusting bracket 10 and the axis of the screw hole of the lower part 12 are on the same straight line,
The straight line passes between the two longitudinally extending portions 13a of the intermediate portion 13.

The frame-shaped bundle height adjusting bracket 10 is formed by heating a material rod and then splitting a middle portion in the longitudinal direction of the rod by a blade along a shaft center to be spread right and left by a blade.
A vertical rib 16 extending in the axial direction and a horizontal rib 17 extending in a direction perpendicular thereto are formed on the outer surface of the bundle height adjusting bracket 10. The ribs 16 and 17 are already formed at the stage of the material rod. However, the ribs 16 and 17 do not have to be formed on the outer surface of the bundle height adjustment fitting 10.

The upper threaded rod 20 is made of steel, and has a screw 21 which can be screwed to the screw 14 of the upper part 11 of the bundle height adjusting bracket 10 on at least a part of the outer periphery in the axial direction. It is screwed into a screw hole in the upper part 11 of the adjustment fitting 10. Similarly, the lower screw rod 30 is made of steel, and has a screw 31 that can be screwed to the screw 15 of the lower part 12 of the bundle height adjusting bracket 10 at least at a part of the outer periphery in the axial direction. It is screwed into the screw hole of the lower part 12 of the adjustment fitting 10.

The large receiving metal fitting 40 is made of steel and is fixed to the upper part of the upper screw rod 20. The support plate 50 is made of steel.
It is fixed to the lower part of the lower screw bar 30. The fixing between the large receiving fitting 40 and the upper screw rod 20 is performed by, for example, caulking or welding. The fixing between the support plate 50 and the lower screw rod 30 is as follows.
For example, by swaging or welding. Large undertaking bracket 4
Reference numeral 0 denotes an L-shaped member, and the support plate 50 is a flat member. A thick double-sided tape 41 is attached as a cushioning material to the upper surface of the large receiving fitting 40, and a large drawing is placed thereon. By doing so, nails and protrusions are not required for temporary attachment at the time of construction, in addition to obtaining the floor noise prevention effect.

The operation of the bundle height adjusting bracket 10 according to the embodiment of the present invention will be described. Construction is performed in the following procedure. First, steel bundle 1
Is placed on the floor concrete under the large pulling, and the lower surface of the large pulling and the large receiving metal fitting 40 are bonded (temporarily fixed) with the double-sided tape 41, and then the bundle height adjusting metal fitting 10 of the steel bundle 1 is turned by hand. After adjusting the supporting force, large undersize fitting 4
0 is fixed with four nails. Finally, the bundle fixing lock nuts 60 and 61 are tightened. The support plate 50 of the steel bundle 1 and the floor concrete are often fixed with an adhesive, but may be fixed with bolts. When it is necessary to adjust the bundle height by floor noise or floor height adjustment after construction, lock nuts 60 and 61 are required.
The upper threaded rod 20 and the lower threaded rod 30 are loosened, and the bundle height adjusting bracket 10 is turned to the right or left.
The bundle height changes due to the relative expansion and contraction through 0, and after the adjustment is completed, the lock nuts 60 and 61 are tightened again.

Since the bundle height adjusting bracket 10 has a frame shape, the upper screw bar 20 and the lower screw bar 30 extend into the space between the two longitudinally extending portions 13a of the intermediate portion 13 of the bundle height adjusting bracket 10. The fitting depth of the upper screw bar 20 and the lower screw bar 30 can be visually checked. Further, since the screws 14 and 15 of the upper part 11 and the lower part 12 of the bundle height adjusting bracket 10 make holes and cut the inner circumference thereof, the screws 14 and 15 are provided over the entire circumference.
The strength of the parts 4 and 15 is large, and the screws 14 and 15 do not deform or separate from the threaded rods 20 and 30.

The frame-shaped bundle height adjusting bracket 10 is formed by heating a material bar and then splitting the middle portion in the longitudinal direction of the bar right and left along the axis, so that a steel plate pressing method is used. The yield is better, the cost is lower, and the productivity is better compared to cutting and shaving. Also, the bundle height adjusting bracket 1
Since the vertical ribs 16 and the horizontal ribs 17 extending in the axial direction are formed on the outer surface of the bracket 0, the operability when adjusting the bundle height by rotating the bundle height adjustment bracket 10 around the axis is good. No tools are required and the strength is about 14 times that of the case without ribs.
%improves.

In the embodiment of the present invention shown in FIG.
Has a connecting portion 13b formed by two longitudinally extending portions 13a being curved and connected in a direction approaching each other in the middle of the longitudinal direction. The connecting portion 13b has no screw hole. By having the connecting portion 13b, it becomes strong against a vertical load. Other configurations and operations are the same as those of the embodiment shown in FIGS. 1 and 2, and the same reference numerals are given to the same parts as those shown in FIGS.

Next, a method of manufacturing a steel bundle according to an embodiment of the present invention will be described. The method for manufacturing the steel bundle 1 according to the embodiment of the present invention has an upper portion 11 having 14 holes, a lower portion 12 having 15 holes, and two longitudinally extending portions 13a extending between the upper portion 11 and the lower portion 12. A frame-shaped bundle height adjusting bracket 10 having an intermediate portion 13 is manufactured, and a screw 21 that can be screwed to the screw 14 of the upper portion 11 of the bundle height adjusting bracket is cut on at least a part of the outer periphery in the longitudinal direction. The upper threaded rod 20 can be screwed into a screw hole in the upper portion 11 of the bundle height adjusting metal fitting 10 and can be screwed into a screw 15 of the lower part 12 of the bundle height adjusting metal fitting 10 on at least a part of the outer periphery in the longitudinal direction. The lower threaded rod 30 having a sharp thread 31 is screwed into a threaded hole in the lower part 12 of the bundle height adjusting bracket 10.

Then, as shown in FIG. 4, the method of manufacturing the bundle height adjusting metal fitting 10 is to cut a bar material having ribs 61 and 62 into a material bar 101 having a predetermined length.
0, a step 110 in which the raw material rod 101 is conveyed to a heating step by a conveyor and heated to 1000 to 1100 ° C. by a gas heating furnace 111 or the like; Blade 12 at the middle part in the direction
1 and two parallel longitudinally extending portions 13 extending longitudinally between the upper portion 11 and the lower portion 12 and between the upper portion 11 and the lower portion 12 by pressing and spreading left and right along the axis.
a frame-shaped body 12 comprising an intermediate portion 13 having a (the intermediate portion 13 may have a connecting portion 13b shown in FIG. 3 in the middle).
A step 120 of manufacturing the frame-shaped body 122 and a step 130 of conveying the frame-shaped body 122 to the upsetting forging step by a conveyor and upsetting and forging the upper part 11 and the lower part 12 of the frame-shaped body 122 to form a head having a predetermined shape. , Drill 143 on the upper part 11 of the frame 122
A hole 141 that penetrates in the axial direction is formed by using a tap 144 on the inner periphery of the hole 141 using a tap 144.
4 and a drill 1 in the lower part 12 of the frame 122.
A step 140 of making a hole 142 penetrating in the axial direction at 43 and cutting the other screw 15 of either the right-handed screw or the left-handed screw on the inner periphery of the hole 142 to manufacture the bundle height adjusting bracket 10. Step 140 is a dedicated automatic line. In step 140, there are drills and taps on the left and right sides, and upper 11 and lower 12
Drilling and tapping are performed on the left and right simultaneously. The cross section of the material rod 101 is circular, and the cross section of the longitudinally extending portion 13a is substantially semicircular.

Then, the bundle height adjusting bracket 10 is moved to step 15
At 0, it undergoes a final quality inspection, is packed at step 160, and is transported or shipped to the next step. The outer surface of the bundle height adjusting metal fitting 10 is usually plated (for example, galvanized). If plating (eg galvanized) is applied,
The plating step 135 is provided after the upsetting forging step 130 and before the screw drilling step 140 (in this case, the screw is raised after plating, so that the screw portion is not plated) or the screw turning is performed. It is provided after the step 140 (in this case, the screw portion is plated and then the screw portion is also plated). In the plating step 135, the frame-shaped body 122 is placed in the plating tank (hot-dip galvanizing tank) 1
61, and is subjected to (zinc) plating.

The operation of the method of manufacturing the steel bundle 1 according to the embodiment of the present invention is as follows. Since the frame-shaped bundle height adjusting metal fitting 10 is manufactured by a pressing step and a head upsetting forging,
The yield is better, the cost is lower, and the productivity is better as compared with other manufacturing methods such as a steel plate pressing method and a cutting method.
Further, since the bundle height adjusting bracket 10 has a frame shape, the fitting depth of the upper screw rod 20 and the lower screw rod 30 can be visually checked, which is convenient when adjusting the bundle height. Further, since the vertical ribs 16 and the horizontal ribs 17 extending in the axial direction are formed on the outer surface of the bundle height adjusting bracket 10, the bundle height adjusting bracket 10 is rotated around the axis to adjust the bundle height. The operability at the time is good, no special tool is required, and the strength is improved by about 14% as compared with the case without the rib.

[0021]

According to the method of manufacturing a steel bundle of claims 1 to 6 and the method of manufacturing a steel bundle of claims 7 to 10, since the bundle height adjusting bracket has a frame shape, the upper screw rod is provided. And the lower threaded rod extends into the space between the two longitudinally extending portions in the middle of the bundle height adjusting bracket, and the fitting depth of the upper threaded rod and the lower threaded rod can be visually checked. In addition, the upper and lower screws of the bundle height adjustment bracket are drilled and cut on the inner circumference, so the screws are all over the circumference, the strength of the thread is large, the thread is deformed, Never leave. According to the method for manufacturing a steel bundle according to claim 2 and the method for manufacturing a steel bundle according to claim 7, the frame-shaped bundle height adjusting bracket heats the material rod, and then moves the intermediate portion in the longitudinal direction of the rod along the axis. Since it is formed by splitting it to the left and right, the yield is better, the cost is lower, and the productivity is better as compared with the steel plate pressing method or the shaving. According to the method of manufacturing the steel bundle of claim 3 and the method of manufacturing the steel bundle of claim 8, since the longitudinal rib extending in the axial direction is formed on the outer surface of the bundle height adjusting bracket, the bundle height adjusting bracket can be used. The operability when adjusting the bundle height by rotating around the shaft center is good, and a dedicated tool is not required, and the strength is improved. According to the steel bundle of the sixth aspect, since the intermediate portion has the connecting portion in the middle, it is strong against the vertical load.

[Brief description of the drawings]

FIG. 1 is a front view of a steel bundle according to an embodiment of the present invention.

FIG. 2 is a side view of the steel bundle according to the embodiment of the present invention.

FIG. 3 is a front view of a steel bundle according to another embodiment of the present invention.

FIG. 4 is a process diagram of a method of manufacturing a steel bundle according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Steel bundle 10 Bundle height adjustment metal fitting 11 Upper part 12 Lower part 13 Middle part 13a Longitudinal extension part 13b Connection part 14, 15, 21, 31 Screw 16 Vertical rib 17 Horizontal rib 20 Upper screw rod 30 Lower screw rod 40 Large undertaker Hardware 41 Double-sided tape 50 Support plate 60, 61 Lock nut 70 Spring washer

Claims (10)

[Claims] 1. An upper part having a hole penetrating in the axial direction and having an inner periphery in which either one of a right-handed screw and a left-handed thread is cut, and a hole penetrating in the axial direction having an inner periphery. A lower part in which either the right-hand thread or the left-hand thread is threaded, and an intermediate part at least partially having two parallel longitudinal extensions extending in the longitudinal direction between the upper part and the lower part. A frame-shaped bundle height adjusting bracket, and a screw that can be screwed to an upper screw of the bundle height adjusting bracket on at least a part of an outer periphery in an axial direction, and is provided on an upper portion of the bundle height adjusting bracket. An upper threaded rod screwed into the hole, and at least a part of the outer periphery in the axial direction is threaded with a screw that can be screwed to a lower screw of the bundle height adjustment bracket. A lower threaded rod screwed into the hole. 2. The frame-shaped bundle height adjusting bracket is formed by heating a material rod and then splitting a middle portion in the longitudinal direction of the rod right and left along an axis.
The steel bundle described. 3. The steel bundle according to claim 1, wherein a longitudinal rib extending in an axial direction and a horizontal rib extending in a direction perpendicular to the longitudinal rib are formed on an outer surface of the bundle height adjusting bracket. 4. The steel bundle according to claim 1, wherein a large receiving bracket is fixed to an upper part of the upper threaded rod, and a support plate is fixed to a lower part of the lower threaded rod. 5. The steel bundle according to claim 4, wherein a double-sided tape is adhered to an upper surface of the large receiving bracket. 6. The intermediate portion has a connecting portion formed by connecting two longitudinally extending portions curved in a direction approaching each other in the middle of the longitudinal direction so as to form a single connecting portion. The steel bundle described. 7. A frame-shaped bundle height adjusting bracket having an upper portion having a screw hole, a lower portion having a screw hole, and two intermediate portions extending between the upper portion and the lower portion is manufactured. An upper threaded rod threaded on a part of the outer periphery of the bundle height adjusting bracket with a screw that can be screwed into the upper thread of the bundle height adjusting bracket is screwed into a hole on the upper portion of the bundle height adjusting bracket, and at least in the longitudinal direction. Manufacturing a steel bundle by screwing a lower screw rod, which is threaded on a part of the outer periphery thereof with a screw that can be screwed into a lower screw of the bundle height adjustment bracket, into a hole at a lower portion of the bundle height adjustment bracket. The method, wherein the bundle height adjusting bracket cuts a bar material into a material bar of a predetermined length, heats the material bar, and moves a heated middle portion of the material bar in the longitudinal direction to the left and right along an axis. Inside two parallel pieces extending longitudinally between the upper and lower parts and the upper and lower parts by splitting and spreading The upper and lower portions of the frame-shaped body are prepared by upsetting and forging into a head of a predetermined shape, and a hole is formed in the upper portion of the frame-shaped body to penetrate in the axial direction. While cutting either the right-hand thread or the left-hand thread on the inner circumference of the hole,
A hole penetrating in the axial direction is made in the lower part of the frame-like body, and the other one of a right-hand screw and a left-hand screw is cut on the inner periphery of the hole to produce a bundle height adjusting bracket. While screwing an upper threaded rod having an outer periphery threaded with a screw that can be screwed into the upper screw of the bundle height adjustment bracket, into an upper hole of the bundle height adjustment bracket,
Screwing a lower screw rod, which is threaded on at least a part of the outer periphery in the longitudinal direction thereof into a screw at a lower part of the bundle height adjusting bracket, into a hole at a lower part of the bundle height adjusting bracket; A method of manufacturing steel bundles manufactured by 8. The steel bundle according to claim 7, wherein a longitudinal rib extending in an axial direction and a horizontal rib extending in a direction perpendicular to the longitudinal rib are formed on an outer surface of the material rod. 9. A steel bundle according to claim 7, wherein a plating step of plating an outer surface of the frame is inserted between the step of forming the head and the step of drilling upper and lower portions of the frame. Production method. 10. The method of manufacturing a steel bundle according to claim 7, wherein a plating step of plating the outer surface of the frame is inserted after the upper and lower screwing steps of the frame.