CN2208651Y

CN2208651Y - Butt-welding head for inner connecting ring of freezing pipe

Info

Publication number: CN2208651Y
Application number: CN 94218443
Authority: CN
Inventors: 王正廷; 伍期建; 周晓敏
Original assignee: BEIJING JIANJING INST OF COAL SCIENTIFIC RESEARCH GENERAL INST
Current assignee: BEIJING JIANJING INST OF COAL SCIENTIFIC RESEARCH GENERAL INST
Priority date: 1994-08-18
Filing date: 1994-08-18
Publication date: 1995-09-27
Anticipated expiration: 2004-08-18

Abstract

The utility model discloses a butt-weld head for inner connecting ring of freezing pipe, which is used for engineering of cutting a well by a freezing method. The utility model is characterized in that the joint position of an upper pipe and a lower pipe is provided with an inscribed hoop and the joint is connected by butt weld. A freezing pipe and the inscribed hoop are both made of seamless steel pipe of low carbon steel and weld performance is good. Compared with the present circumscribed hoop joint and a screw-thread joint which are used for freezing engineering in China and in abroad, the utility model can improve stress condition, can enhance the loading capacity of the joint, and plays a positive role in preventing fracture of the freezing pipe. Simultaneously, the butt-weld head for inner connecting ring of freezing pipe has the advantages of simple construction technics, no joint processing with screw thread and engineering cost saving.

Description

Butt-welding head for inner connecting ring of freezing pipe

The utility model relates to the freezing pipe joint that a kind of freeze-wellboring engineering is used, i.e. box cupling butt joint in the freezing pipe.

Freeze-wellboring has had nearly 40 years history in China.In colliery shaft building engineering, be used widely, be used to handle the sinking shaft of caving grounds such as drift sand, mud and aquifer water-bearing stratum.Along with the development of producing, the intensification of mine shaft depth, freeze-wellboring faces the difficult problem of a sternness, i.e. the fracture of freezing pipe, it directly has influence on the success or failure that pit shaft is built.Fracture because of freezing pipe repeatedly took place in the home and abroad colliery freeze-wellboring engineering caused the serious accident of flooding well and collapsing well.The easiest joint area that occurs in of fracture of freezing pipe.External freezing pipe joint adopts and is threaded.And China's freezing pipe joint has outer box cupling to connect and is threaded two kinds.Find in the practice that fracture and salt seepage easily take place these two kinds of joints; And the thread connecting joint amount of finish is big, cost is high.

The purpose of this utility model is for overcoming present freezing pipe in the deficiency aspect the joint.A kind of joint of new design, promptly freezing pipe two pipe coupling places install an interior box cupling, and the butt welding connection, to improve stressing conditions, improve bearing capacity.

The utility model content is a kind of novel welded structure that freezing pipe connects.The interior box cupling that can improve the joint welding stressing conditions and have leading role promptly is housed in the freezing pipe joint, and the top tube and down tube end butt welding in being set on the box cupling connects.

Freezing pipe of the present utility model and interior box cupling all adopt the good low carbon steel steel pipe of welding performance.

The utility model has the advantages that:

1. the bearing capacity height of freezing pipe joint.Machine finite element Force Calculation and analysis as calculated, interior box cupling can reduce near flexural stress and the shearing stress the position while welding effectively.Butt welding simultaneously connects has avoided the irrationality of outer box cupling welded structure in terms of mechanics.

2. improve the stress condition of freezing pipe.Because the external diameter of joint equates with other position of freezing pipe, has reduced the stratum freezing pipe is retrained, and can reduce the temperature stress and the displacement constraint stress of freezing pipe.

3. construction process is easy.Welded structure is simple, saves half welding engineering amount than outer box cupling joint.Adopt Low Carbon Steel Pipe, welding performance is preferably arranged.Construction quality can be guaranteed.

4. obvious economic benefit is arranged.Freezing pipe can adopt the common low carbon seamless steel pipe, and the source of goods is wide, need not special working joint, and price is starkly lower than the steel pipe of threaded joint.

Description of drawings:

Fig. 1 is the utility model

Fig. 2 is the outer box cupling jointing of freezing pipe

Fig. 3 is the thread connecting joint of freezing pipe

Below in conjunction with description of drawings embodiment of the present utility model, see box cupling butt joint figure in the freezing pipe.［ 1 ］ be to go up pipe, continued connecting, ［ 2 ］ are to manage down, have transferred in the boring, ［ 3 ］ are interior hoops.Freezing pipe is generally selected the seamless steel pipe of 108～159mm for use, wall thickness 5～9mm, and freezing pipe and box cupling are all selected low carbon steel for use.

Transfer be connected freezing pipe before to perform following preparatory work.

1. process interior box cupling, interior box cupling external diameter is than the little 1～2mm of freezing pipe internal diameter, and wall thickness 4mm grows 120～200mm, makes of the low carbon steel seamless steel pipe.

2. carry out groove processing to freezing pipe end, slope angle α is 30～45 degree, cleans the joint area and the interior box cupling of freezing pipe afterwards, removes iron rust and greasy dirt.

3. interior box cupling is installed in advance an end of steel pipe, and adopts spot welding method to fix interior box cupling, only require uniform 3 points.

4. to fall pipe in the pipe process in order preventing down, the fixing point must to be set near the end of freezing pipe temporarily, method is the long reinforcing bars of two 50mm of symmetrical spot welding, is used for clamp and fixes.

The transferring and be connected of freezing pipe:

Freezing pipe is vertically transferred, an end of box cupling up in will exposing, following pipe ［ 2 ］ is fixed on hell with clamp, weld bond is apart from about the 1.5m of ground, pipe ［ 1 ］ is gone up in lifting again, and last pipe ［ 1 ］ aligns, puts with following pipe is vertical under the leading role of interior box cupling, pipe just can weld then to tightly up and down.Select J422 for use, φ 3.2 welding rods.Welding quality be to pay attention to during manual welding, undercut, overlap down do not allowed, problems of welded quality such as slag inclusion, cold and hot crackle.The cooling in air of welding back can be descended pipe in 10 minutes.

Claims

1, a kind of interior box cupling butt joint of freezing pipe that comprises pipe, box cupling is characterized in that the interior box cupling that improves the joint welding stressing conditions and have leading role is housed in the freezing pipe joint, and the top tube and down tube end butt welding in being set on the box cupling connects.

2,, it is characterized in that pipe, following pipe and interior box cupling all adopt the ordinary low-carbon steel steel pipe as box cupling butt joint in the said freezing pipe of claim 1.