JP3242604B2 - How to connect steel pipes - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for connecting steel pipes.
The present invention relates to a method of connecting steel pipes used for forming a foundation ground, retaining soil, underground foundation piles and columns for supporting an upper structure, and a pipe roof construction method for horizontally pushing and pushing steel pipes.

[0002]

2. Description of the Related Art Conventionally, steel pipe piles, steel pipe supports and beams, etc.
It is used as a structure having a required length in design. When steel pipes need to be lengthened due to restrictions on construction such as transportation, sky restriction, work space of a propulsion base, etc., a method of connecting a plurality of steel pipes on site is adopted. As a method for connecting steel pipes, a welding method or the like is employed locally. At present, construction is performed by joining with bolts or the like in addition to the joining method by welding.

In such a conventional joining method by field welding, after the preceding first steel pipe is driven or driven, the succeeding second steel pipe is accurately butted against the first steel pipe, and a gap of several millimeters is formed. It is secured and welded with a welding machine. In order to secure a gap of several millimeters to secure the strength of the weld, a crane for suspending the second steel pipe and a gantry for fixing the position are required. In addition, welding is performed by manual welding by almost input or automatic welding in which a welding machine is wrapped around a steel pipe and welded by installing a device for holding the welding machine around the steel pipe at a joint portion. In the case of manual welding, since the welding position is almost in the middle position, the working conditions are poor, the working efficiency is low, and a great amount of construction time is required. Further, in the case of automatic welding, considerable accuracy is required for the installation accuracy of the device for the welding, which requires a great amount of time for installation and also affects the quality of welding. As described above, since a large amount of time is required for joining steel pipes, at present, steel pipes are not used on-site with time constraints.

[0004] In the joining method using bolts, since the steel pipe has a curvature, it takes time to align the bolt holes, and when the diameter of the steel pipe is small, it becomes difficult to tighten the bolt. In the case of joining with bolts, the heads and nuts of the bolts protrude from the main body steel pipe and the joint steel pipe. For this reason, when the steel pipes are adjacent to each other or, for example, it interferes with an earth removal facility (for example, an auger screw) mounted inside the steel pipes, and also acts as a resisting force during driving or propulsion. There is also an impact on construction costs, such as the need to do so.

Further, there has been proposed a method of connecting steel pipe piles on site by using an adhesive instead of welding. For example, Japanese Patent Application Laid-Open No. 5-156628 discloses that one of steel pipe piles to be joined is fixed to a joint pipe, the other steel pipe pile is fitted to the joint pipe, and the pile is joined to the joint of both steel pipe piles. After performing temporary fixing to enable transmission of the buried construction load,
There is disclosed a joint method of a steel pipe pile in which an adhesive is injected into a gap between a joint pipe and the other steel pipe pile, and the pile is buried without curing the adhesive. In this method, a steel pipe is buried by temporary fixing, and an epoxy resin or the like having a long curing time is usually used as an adhesive, and it takes a long time until the connection strength of the steel pipe by the adhesive is obtained. It is.

[0006]

When the steel pipe piles are connected by welding, several hours are required for the welding operation. For example, staking steel pipes inside or below the track,
It must be performed in a short time, that is, during a power outage period between the last train that the train does not pass and the first train of the next day, so that the conventional time-consuming connection method cannot be used. In a site where there is a restriction on such an operation time or an overhead obstacle such as an overhead line, there is a problem with the conventional connection method, and it has been required to reduce the time for connecting the steel pipe piles.

Further, when the method disclosed in Japanese Patent Application Laid-Open No. 5-156628 is performed, it is impossible to check whether the adhesive is hardened because it is driven before the adhesive is hardened. There is a high possibility that the adhesive interface with the agent is peeled off and the adhesive strength is reduced. Further, there is a great possibility that the adhesive may cause poor curing due to moisture or moisture in the soil. In order to ensure the adhesion, it is preferable to perform the driving after the adhesive is cured. By doing so, a connected body with perfect adhesive strength can be obtained.

The present invention has been made in view of the above circumstances, and a method of connecting steel pipes that can easily connect steel pipes, has good adhesiveness, and can greatly reduce the work time on site. The purpose is to provide.

[0009]

That is, the present invention relates to a driving, erection or connecting method in which a first steel pipe and a second steel pipe are connected to each other at a steel pipe end via a hollow steel pipe in a short time.
Is a connecting method of a steel pipe for pushing and pushing , wherein a bolt hole is formed in a joint part and a joint steel pipe of the first steel pipe and the second steel pipe.
And joints and joints of the first steel pipe and the second steel pipe
A steel pipe is fitted with a bolt hole aligned, and a bolt for maintaining a constant gap between the steel pipe and the joint steel pipe in the bolt hole is provided.
Through to form a gap and fixed with nuts, and sealing the butt portion of the first steel tube and the second steel pipe, and after sealing one of the bottom of the joint steel, steel pipes or fittings in the gap of the fixed interval From an inlet provided in the steel pipe, the mixture is substantially cured at −10 ° C. to 40 ° C. by mixing an acrylic monomer, a polymerization initiator and a decomposition accelerator, and the acrylic monomer is methyl (meth) acrylate, It contains one or more of 2-hydroxyethyl (meth) acrylate, epoxy (meth) acrylate, and terminal (meth) acryl-modified liquid polybutadiene, the polymerization initiator is an organic peroxide, and the decomposition accelerator is thiourea. Derivatives and organometallic salts
A two-part cold-setting acrylic adhesive having a viscosity of 5,000 cps or less and having an adhesive strength capable of driving or pushing in a steel pipe within 30 minutes after the injection of the adhesive is injected and filled. A method for connecting steel pipes, wherein the steel pipe is hardened, and the first steel pipe and the second steel pipe are bonded to a joint steel pipe to be connected in a short time .

In the method for connecting steel pipes according to the present invention, the first two-liquid cold-setting acrylic adhesive is provided in a gap between the steel pipe and the joint steel pipe after the first steel pipe and the second steel pipe are fitted to a joint part of the joint steel pipe. Filling and curing agent to connect, or before
The joint between the first and second steel pipes and the joint steel pipe
Open the belt holes, Bol on one joint portion of the first steel tube and the joint portion the joint steel pipe of one of the steel pipe of the second steel pipe
Fitted together bets hole, ball of one of the steel pipe and fittings steel the
The belt holes, to form a gap and fixed with nuts through the bolt for keeping the gap between the steel pipe and fittings steel pipe at predetermined intervals,
After sealing the bottom of the joint steel pipe, an acrylic monomer, a polymerization initiator and a decomposition accelerator are substantially injected through an inlet provided in the steel pipe or the joint steel pipe at the predetermined interval . The mixture is cured at −10 ° C. to 40 ° C. by mixing, and the acrylic monomer alone is methyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, epoxy (meth) acrylate, or terminal (meth) acryl-modified liquid polybutadiene. Or two or more thereof, wherein the polymerization initiator is an organic peroxide, and the decomposition accelerator is a thiourea derivative or an organic metal salt.
A two-part, room temperature curable acrylic adhesive with a viscosity of 5,000 cps or less that develops an adhesive strength that enables the steel pipe to be driven or pushed in within 30 minutes after the injection of the adhesive. After bonding and fixing, the other steel pipe is fitted to the other joint part of the joint steel pipe by sealing the butt portion of both steel pipes, aligning the bolt holes, and fitting the other steel pipe and the bolt holes of the joint steel pipe. Through the bolts to maintain a constant gap between the steel pipe and the joint steel pipe.
After forming a gap by fixing with a nut, the same two-liquid cold-setting acrylic adhesive as described above is injected into the gap from an inlet provided in a steel pipe or a joint steel pipe, and filled and cured to be bonded. The connecting method is preferred.

The joint steel pipe is an outer pipe joint steel pipe having an inner diameter larger than the outer diameter of the first steel pipe and the second steel pipe, and the first steel pipe and the second steel pipe are connected to each other through the inside of the outer pipe joint steel pipe. The method of connecting steel pipes connected at the end of the steel pipe is preferred.

The joint steel pipe is an inner pipe steel pipe having an outer diameter smaller than the inner diameter of the first steel pipe and the second steel pipe, and the first steel pipe and the second steel pipe are connected to each other through the outer side of the inner pipe steel pipe. The method of connecting steel pipes connected at the end of the steel pipe is preferred. A method of connecting steel pipes in which a bolt for keeping the gap between the steel pipe and the joint steel pipe at a constant interval is provided, and then an acrylic adhesive is filled.

As the acrylic adhesive, it is preferable to use an acrylic adhesive exhibiting an adhesive strength capable of driving a steel pipe within 30 minutes after the injection of the adhesive. It is preferable that the acrylic adhesive is an acrylic adhesive which is cured by substantially mixing a polymerization initiator and a decomposition accelerator.

[0014]

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an outer pipe joint steel pipe having an inner diameter larger than the outer diameter of the first steel pipe and the second steel pipe, or an inner pipe joint steel pipe having an outer diameter smaller than the inner diameter of the steel pipe. After fitting into the joint between the first steel pipe and the second steel pipe, an acrylic adhesive that rapidly hardens is injected and hardened into the gap between the first steel pipe and the second steel pipe and the joint steel pipe, and the steel pipes are connected early, This is a method of connecting steel pipes that enables construction such as driving and propulsion.

Further, in order to further shorten the construction time, a steel pipe previously joined to one of a first steel pipe and a second steel pipe by using an acrylic adhesive is attached to one of a front part and a rear part of one of the first steel pipe and the second steel pipe. In use, the other first steel pipe and the second steel pipe may be fitted on the joint steel pipe at the site, and an acrylic adhesive may be injected into the gap between the steel pipe and the joint steel pipe, hardened, and connected.

The method of connecting steel pipes according to the present invention is to form or pierce steel pipes in the ground, in particular, to form a foundation ground, to retain soil, to propel steel pipes horizontally, in addition to underground foundation piles and columns for supporting an upper structure. It can be used for the construction of the pipe roof method of pushing in.

[0017]

Embodiments of the present invention will be described below with reference to the drawings, for example, a steel pipe pile.

Embodiment 1 FIG. 1 is an explanatory view showing an embodiment of a method for connecting steel pipes according to the present invention. FIG. 1 (a) is an explanatory sectional view and FIG. 1 (b) is an explanatory bottom view. FIG. 2 is an explanatory sectional view showing a connected body of steel pipes connected by the method of FIG.

FIGS. 1 and 2 show the first steel pipe pile and the second steel pipe pile as the first steel pipe and the second steel pipe. It is a figure which shows the example which joins the outer pipe joint steel pipe which has this, and connects a 2nd steel pipe pile on site.

The first steel pipe 1 and the outer pipe joint steel pipe 2a are joined in advance at a factory or the like. A joint at the end of the first steel pipe 1 is fitted to the outer pipe steel pipe 2a, and a gap 9a is provided between the first steel pipe 1 and the outer pipe steel pipe 2a.

In this case, if necessary, a bolt hole 12 is formed in the first steel pipe 1 and the outer pipe joint steel pipe 2a, and a bolt 10 for maintaining a constant gap between the steel pipe and the joint steel pipe.
And fixed with a nut 11. Preferably, a plurality of bolts 10 are provided. As a method of fixing with a bolt and a nut, for example, a method of welding the nut to the inside of a steel pipe or bonding and fixing the nut with an adhesive, and then screwing the bolt is used. In order to keep the gap between the steel pipe and the joint steel pipe at a constant interval, a spacer may be inserted into the gap between the steel pipe and the joint steel pipe.

Thereafter, the bottom portion of the outer pipe joint steel pipe 2a is welded and sealed with a mastic elastic sealing material or a rubber O-ring to form a seal portion 5, which is provided below the outer pipe joint steel pipe 2a. The gap 9 a is filled with the acrylic adhesive 4 from the inlet 6. In this case, an air vent hole may be provided to evacuate the air in the gap 9a.

Next, when the first steel pipe 1 and the second steel pipe 3 are connected on site, the butted portions of the two steel tubes are sealed with a mastic elastic sealing material, rubber packing, a fast-curing liquid gasket, or the like. After forming 8,
The second steel pipe 3 is fitted from the other of the outer pipe joint steel pipe 2a, and a gap 9b is provided between the second steel pipe 3 and the outer pipe joint steel pipe 2a. In this case, the bolt 10 and the nut 11 are passed through in the same manner as described above.

The acrylic adhesive 4 is injected and filled into the gap 9b from the injection port 7 located slightly above the butt seal portion 8 provided in the outer pipe joint steel pipe 2a and then hardened. A connected body of the steel pipe shown is obtained. In this case, an air vent hole may be provided to evacuate the air in the gap 9b.

In the present invention, an acrylic adhesive is injected into the adhesive as described above. The acrylic adhesive has a short curing time and can be applied in a short time. The curing time refers to the time from the filling of the gap to the development of the adhesive strength at which the pile can be driven. By using an acrylic adhesive, curing can be performed at 23 ° C. in a short curing time of 3 minutes to 30 minutes, preferably 3 minutes to 15 minutes.

The acrylic adhesive has a viscosity of 5,000 cp
s or less, and since there is no sudden increase in viscosity at low temperatures such as epoxy resin, the gap can be sufficiently filled with an adhesive.

In the conventional resin-based adhesive, the amount of the adhesive to be mixed had to be strictly measured and completely mixed. However, it was not necessary to strictly measure the amount of the acrylic adhesive to be mixed. It is possible to use a simple applicator or a mixer, and work on site can be easily performed.

The acrylic adhesive means an adhesive made of an acrylic monomer or a mixture containing the acrylic monomer and cured at room temperature, for example, at -10 ° C. to 40 ° C. It is preferable to use an initiator and a decomposition accelerator together.

The acrylic monomers include (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth)
Acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, dicyclopentenyloxyalkyl (meth) acrylate, polyethylene glycol (meth) acrylate , Polypropylene glycol (meta)
Acrylate, dimethylaminoethyl (meth) acrylate, polyethylene glycol di (meth) acrylate, 1,4-butanediol (meth) acrylate, epoxy (meth) acrylate and trimethylolpropane tri (meth) acrylate and terminal (meth) acrylic modified And liquid polybutadiene. These can be used alone or in combination of two or more.

Of the above-mentioned acrylic monomers, methyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, epoxy (meth) acrylate, and terminal (meth) acryl-modified liquid polybutadiene are particularly preferred. These can be used alone or in combination of two or more.

The acrylic adhesive used in the present invention can use an acrylic monomer and another radical polymerizable monomer in combination, but the other monomers used here are not particularly limited. Without, monofunctional monomers such as styrene, acrylonitrile, vinyl acetate, acrylamide, etc., and polyfunctional monomers such as divinylbenzene, triallyl cyanurate and triallyl isocyanurate may be used alone or in combination of two or more. It is possible.

It is preferable that the acrylic adhesive used in the present invention is an acrylic adhesive which is cured by substantially mixing a polymerization initiator and a decomposition accelerator. As is well known, the curing of acrylic adhesive proceeds by thermal polymerization without adding a curing agent, but when curing acrylic adhesive at civil engineering construction sites, unlike acrylic chemical plants, it is stable. It is difficult to secure and manage the heat source, and it is necessary to promote the curing reaction by a simpler method. For that purpose, it is preferable to promote curing at room temperature by mixing a polymerization initiator and a decomposition accelerator.

As the polymerization initiator of the acrylic adhesive used in the present invention, a peroxide or an azo compound used as a radical polymerization initiator is preferably used. There is no limitation, for example, peroxides include cumene hydroperoxide, organic peroxides such as methyl ethyl ketone peroxide and benzoyl peroxide, and inorganic peroxides such as potassium persulfate and ammonium persulfate. Azobisisobutyronitrile and the like. Of these, organic peroxides are preferred in terms of curability.

The decomposition accelerator is a compound that accelerates the decomposition of the polymerization initiator. Specific examples thereof include thiourea derivatives such as diethylthiourea, amines such as N, N-diethyl-p-toluidine, and naphthenic acid. There are organic acid metal salts such as cobalt and cobalt octylate, and organic metal chelate compounds such as copper acetylacetonate, and these can be used alone or in combination of two or more. Of these, organic acid metal salts and organic metal chelate compounds are preferred in terms of curability.

Among the acrylic adhesives, a two-part, room temperature curable acrylic adhesive is preferable because the viscosity can be adjusted to be low and the injection can be completed in a short time. The two-component cold-setting acrylic adhesive refers to an acrylic adhesive that is divided into two liquids, an A agent and a B agent, and the A agent contains a polymerization initiator and the B agent contains a curing accelerator. Two-part cold curing type acrylic adhesive is A
The adjustment of the mixing ratio of the agent and the agent B does not have to be strict, and even a simple mixture has a large adhesiveness, so that it can be easily operated with a simple applicator or mixer.

Embodiment 2 FIG. 3 is an explanatory view showing another embodiment of the method for connecting steel pipes according to the present invention, wherein FIG. 3 (a) is a sectional explanatory view and FIG. 3 (b) is a bottom explanatory view. . FIG. 4 is an explanatory sectional view showing a connected body of steel pipes connected by the method of FIG.

FIGS. 3 and 4 show that the first steel pipe pile and the second steel pipe are used as the first steel pipe and the second steel pipe, and the outer diameter of the first steel pipe pile is smaller than the inner diameter of the first steel pipe pile. It is a figure which shows the example which joins the inner pipe joint steel pipe which has a diameter, and connects a 2nd steel pipe pile on site.

The first steel pipe 1 and the inner pipe joint steel pipe 2b are joined in advance at a factory or the like. A joint at the end of the first steel pipe 1 is fitted to the inner pipe joint steel pipe 2b, and a gap 9a is provided between the first steel pipe 1 and the inner pipe joint steel pipe 2b.

Thereafter, the bottom portion of the inner pipe joint steel pipe 2b is welded and sealed with a mastic elastic sealing material or a rubber O-ring to form a seal portion 5, which is provided below the inner pipe joint steel pipe 2b. The gap 9 a is filled with the acrylic adhesive 4 from the inlet 6.

Next, when the first steel pipe 1 and the second steel pipe 3 are connected on site, the butted portions of the two steel tubes are sealed with a mastic elastic sealing material, rubber packing, a fast-curing liquid gasket, or the like. After forming 8,
The second steel pipe 3 is fitted from the other of the inner pipe joint steel pipes 2b, and a gap 9b is provided between the second steel pipe 3 and the inner pipe joint steel pipe 2b.

An acrylic adhesive 4 is injected into a gap 9b from an injection port 7 provided in the inner pipe joint steel pipe 2b and located slightly above the butt seal portion 8, and then hardened. A connected body of the steel pipe shown is obtained.

In addition, after fitting the first steel pipe and the second steel pipe to the joint of the joint steel pipe, the gap between the first steel pipe and the second steel pipe and the joint steel pipe is filled with an acrylic adhesive to be hardened and connected. May be.

[0043]

As described above, according to the present invention, it is possible to obtain a joint of steel pipes which is easy to connect with steel pipes and has good adhesiveness. The connection of the steel pipes is completed by fitting into the seam of the second steel pipe, injecting a fast-curing acrylic adhesive into the gap between the steel pipe and the joint steel pipe, and curing it early. Therefore, compared with the conventional method of connecting steel pipes by a welding method or the like, the working efficiency can be improved and the working time can be significantly reduced, which is extremely effective in a site where the working time is restricted.

In the conventional method, it takes several hours or more to connect one joint, but in the method of the present invention, the operation time can be reduced to at most 30 minutes, which is a great reduction. .

Also, by filling an acrylic adhesive, particularly a two-part cold curing type acrylic adhesive, the viscosity can be adjusted to be lower than other adhesives, so that the injectability is good and the curing time is short, so that Connection of steel pipes can be performed in a short time.

Furthermore, since the adhesive is driven after the adhesive is hardened, a connected body having a perfect adhesive strength can be obtained without a decrease in the adhesive strength due to vibration at the time of driving or moisture in the soil.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing one embodiment of a method for connecting steel pipes of the present invention.

FIG. 2 is an explanatory sectional view showing a connected body of steel pipes connected by the method of FIG. 1;

FIG. 3 is an explanatory view showing another embodiment of the method for connecting steel pipes of the present invention.

FIG. 4 is an explanatory sectional view showing a connected body of steel pipes connected by the method of FIG. 3;

[Description of Signs] 1 First steel pipe 2a Outer pipe joint steel pipe 2b Inner pipe joint steel pipe 3 Second steel pipe 4 Acrylic adhesive 5 Seal part 6,7 Injection port 8 Butt seal part 9a, 9b Gap 10 Bolt 11 Nut 12 Bolt hole

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor: Kimitaka Nishimura 2-6-1, Yoyogi, Shibuya-ku, Tokyo East Japan Railway Company (72) Inventor: Nokazu Hagiya 3-17-11 Shibaura, Minato-ku, Tokyo No. East Japan Railway Company (72) Inventor Jun Yamato 2-6-6 Yoyogi, Shibuya-ku, Tokyo East Japan Railway Company (72) Takashi Torigoe 1-4-1, Yurakucho, Chiyoda-ku, Tokyo Inside Electrochemical Industry Co., Ltd. (72) Inventor Hideya Soma 1135 Nakamura, Shibukawa City, Gunma Prefecture Inside Electrochemical Industry Co., Ltd. Shibukawa Plant (56) References JP-A-7-279167 (JP, A) −49832 (JP, U) Actually open 63-130546 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) E02D 5/24

Claims (4)

(57) [Claims] 1. A striking that the first steel tube and the second steel pipe connecting in a short time through the hollow joint steel pipe at their steel ends
In the method of connecting steel pipes for insertion, erection, or push- in, a bolt hole is formed in a joint part and a joint steel pipe of the first steel pipe and the second steel pipe, and the first steel pipe and the second steel pipe are formed.
Fit the joint between the pipe and the steel pipe with the bolt holes aligned
And, the gap and fixed with nuts through the bolt for keeping the gap between the steel pipe and fittings steel pipe at predetermined intervals to said bolt hole
After forming and sealing the butted portion of the first steel pipe and the second steel pipe and sealing one bottom of the joint steel pipe, the injection pipe provided in the steel pipe or the joint steel pipe in the gap at the predetermined interval substantially removes The mixture is cured at −10 ° C. to 40 ° C. by mixing an acrylic monomer, a polymerization initiator and a decomposition accelerator, and the acrylic monomer is methyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, Epoxy (meth) acrylate, terminal (meth) acrylic modified liquid polybutadiene singly or in combination of two or more, the polymerization initiator is an organic peroxide, the decomposition accelerator is a thiourea derivative and an organic metal salt from two It becomes, and the adhesive 2-liquid cold-cure type a follows viscosity 5000cps expressing bond strength implantation or promotion push is enabled the steel within 30 minutes after injection of Connecting method of the steel pipe, characterized in that filled by injecting Lil-based adhesive, which is linked with a short time curing and bonding the first steel tube and the second steel pipe and fittings steel pipe. 2. A joint between the first steel pipe and the second steel pipe.
And drilled bolt holes in the joint steel pipe, the one combined bolt holes in the joint portion of the fitted first steel pipe and fittings steel pipe joint portion of one of the steel pipe of the second steel pipe, the one of the steel pipe and fittings the bolt hole of the steel pipe, and fixed with nuts through the bolt for keeping the gap between the steel pipe and fittings steel pipe at a constant distance
After forming a gap and sealing the bottom of the joint steel pipe,
The mixture is cured at −10 ° C. to 40 ° C. by substantially mixing an acrylic monomer, a polymerization initiator, and a decomposition accelerator from an injection port provided in a steel pipe or a joint steel pipe in the gap at a predetermined interval. The monomer is methyl (meth) acrylate, 2-
It contains hydroxyethyl (meth) acrylate, epoxy (meth) acrylate, terminal (meth) acryl-modified liquid polybutadiene alone or in combination of two or more, the polymerization initiator is an organic peroxide, the decomposition accelerator is a thiourea derivative and It consists of two kinds of organic metal salts, and after injection of adhesive 3
A two-liquid, room-temperature-curable acrylic adhesive having a viscosity of 5,000 cps or less that develops adhesive strength that enables the steel pipe to be driven or pushed in within 0 minutes is injected, filled, cured, bonded and fixed, and then the other steel pipe is fixed. Seal the butt of both steel pipes to the other joint of
The other steel pipe and the joint steel pipe have bolt holes
, After forming the gap and secure it with a nut through a bolt for keeping the gap between the steel pipe and fittings steel pipe at predetermined intervals, from the injection port formed in a steel pipe or fitting steel pipe in the gap, the same 2 2. The method for connecting steel pipes according to claim 1, wherein a liquid-room temperature-setting acrylic adhesive is injected, filled, hardened, and bonded. 3. The joint steel pipe is an outer pipe joint steel pipe having an inner diameter larger than the outer diameter of the first steel pipe and the second steel pipe, and the first steel pipe and the second steel pipe pass through the inside of the outer pipe joint steel pipe. 3. The method of connecting steel pipes according to claim 1, wherein the steel pipes are connected at their ends. 4. The joint steel pipe is an inner pipe joint steel pipe having an outer diameter smaller than the inner diameter of the first steel pipe and the second steel pipe, and the first steel pipe and the second steel pipe pass through the outside of the inner pipe joint steel pipe. 3. The method of connecting steel pipes according to claim 1, wherein the steel pipes are connected at their ends.