CN-122007561-A - Cannula welding piece penetrating type inner cavity back welding protection device, manufacturing method and using method

CN122007561ACN 122007561 ACN122007561 ACN 122007561ACN-122007561-A

Abstract

The invention relates to a welding protection device for a penetrating type inner cavity back of a cannula welding part, a manufacturing method and a using method, and is applicable to the field of welding of cannula and transition sections. The invention aims to solve the problems of poor welding quality consistency, unstable protection effect, poor tooling universality and low production efficiency in the welding back argon protection of the insertion pipe and the transition section in the prior art, a plurality of cylinder fixing pieces are uniformly distributed on the side wall of a protection cylinder along the radial direction, the protection cylinder is arranged on the insertion pipe welding piece through the plurality of cylinder fixing pieces, and a plurality of protection gas conveying pipes are arranged outside the protection cylinder. The method comprises the steps of rolling a rectangular steel plate into a cylinder, fixing welding positions, welding fixing connecting plates at two ends of a protection cylinder, welding four nuts on the protection cylinder, connecting a fastening bolt with a nut on each nut in a threaded manner, and inserting a protection gas conveying pipe on the two fixing connecting plates.

Inventors

SUN BAIHUI
ZHAO LONGQING
ZHOU YANG
DONG LIWU
XIA DING
WU HAITAO
XU JIAN
LIU RUIHANG
LI GANG
BI WENJING

Assignees

哈尔滨汽轮机厂有限责任公司
哈电发电设备国家工程研究中心有限公司

Dates

Publication Date: 20260512
Application Date: 20260313

Claims (10)

1. The back welding protection device for the penetrating inner cavity of the cannula welding part is characterized by comprising a protection cylinder (1), a plurality of cylinder fixing parts (2) and a plurality of protection gas conveying pipes (3); The protection barrel (1) is circular barrel, a plurality of barrel fixing pieces (2) are uniformly distributed on the side wall of the protection barrel (1) along the radial direction, the protection barrel (1) is installed on the cannula welding piece through the barrel fixing pieces (2), a plurality of protection gas conveying pipes (3) are arranged outside the protection barrel (1), and the gas outlets of the protection gas conveying pipes (3) are arranged in the protection barrel (1).
2. The device for protecting the back welding of a penetrating inner cavity of a cannula weldment according to claim 1, further comprising two fixed connection plates (4); The two fixed connection plates (4) are oppositely arranged in parallel, and the two ends of the protection cylinder body (1) are respectively and fixedly arranged on the fixed connection plates (4).
3. The device for welding and protecting the back of the penetrating inner cavity of the cannula welding part according to claim 2 is characterized in that the fixed connecting plate (4) is an annular plate, and each end of the protecting cylinder (1) is welded and fixed with the inner circular surface of the fixed connecting plate (4) respectively.
4. A penetrating type inner cavity back welding protection device for cannula welding parts according to claim 3, wherein a plurality of protective gas conveying pipes (3) are inserted on two fixed connecting plates (4).
5. The device for protecting back welding of penetrating type inner cavity of cannula welding part according to claim 1, wherein the cylinder fixing part (2) comprises a fastening bolt and two nuts, wherein one nut is fixedly arranged on the protecting cylinder (1) in a welding way, the other nut is arranged on the fastening bolt in a threaded connection way, and the fastening bolt is arranged on the nut fixed on the protecting cylinder (1) in a threaded connection way.
6. A method for manufacturing a penetrating type inner cavity back welding protection device of a cannula welding part according to any one of claims 1 to 5, wherein the method is realized according to the following steps: Preparing four protective gas conveying pipes (3), preparing rectangular steel plates, preparing two fixed connecting plates (4), and preparing four cylinder fixing pieces (2), wherein each cylinder fixing piece (2) comprises a fastening bolt and at least two nuts; Rolling the rectangular steel plate into a cylinder, performing spot welding fixation on the welding position, and performing full-welded fixation after the spot welding fixation to form a protection cylinder (1); welding and fixing two fixed connecting plates (4) at two ends of the welded protection cylinder (1); Welding and fixing four nuts on the protection cylinder body (1), wherein two adjacent nuts are arranged at 90 degrees in the radial direction of the protection cylinder body (1), each nut is connected with a fastening bolt with a nut in a threaded manner, and the fastening bolts are inserted on the side wall of the protection cylinder body (1); and fifthly, four protection gas conveying pipes (3) with the diameter of phi 6 and the length of about 500mm are inserted and mounted on the two fixed connecting plates (4).
7. The method for manufacturing a tube welding piece penetrating type inner cavity back welding protection device according to claim 6, wherein the diameter of the protective gas conveying tube (3) is about 500mm in length of phi 6.
8. The method for manufacturing the back welding protection device for the penetrating type inner cavity of the cannula welding part according to claim 6, wherein the number of nuts in each cylinder fixing part (2) is two or three.
9. The method of claim 6, wherein the rectangular steel plate has a length of 800mm and a width of 200mm.
10. A method for using a penetrating lumen back welding protecting device of a cannula weldment according to any one of claims 1 to 5, wherein the method is implemented in the following manner: The protection barrel (1) is sleeved outside the cannula welding part, the protection barrel (1) is fixed on the cannula welding part through four barrel fixing parts (2), the threaded end of each fastening bolt on the barrel fixing part (2) is propped against the outer side wall of the cannula welding part, a fixed connecting plate (4) above the protection barrel (1) is sealed with an arc-shaped transition section through a high-temperature-resistant adhesive tape, a protection gas conveying pipe (3) is connected with an argon gas source and supplied with gas, so that a stable back argon protection environment is formed inside the protection barrel (1), welding work is carried out after argon is filled in the space of the protection barrel (1), after welding is completed, argon supply is stopped, a tool is removed, the inside of the cannula and the back of a welding line are checked, and welding quality is confirmed to meet requirements.

Description

Cannula welding piece penetrating type inner cavity back welding protection device, manufacturing method and using method Technical Field The invention relates to a welding protection device for an insertion pipe welding piece, a manufacturing method and a using method, in particular to a back welding protection device for a penetrating inner cavity of an insertion pipe welding piece, a manufacturing method and a using method. Background In high-temperature power equipment such as a steam turbine, a gas turbine, a heavy-duty gas turbine and the like, a main steam valve assembly part, a combustion system and related pipeline components are core components for guaranteeing stable operation of the equipment, and insertion pipe and transition section structures are commonly arranged in the components, so that the core functions of the equipment are that stable conveying of high-temperature and high-pressure media and reliable connection among the structures are realized, and the operation safety and the service life of the equipment are directly determined. In the long-term service process of the insertion pipe and the transition section thereof, the insertion pipe and the transition section thereof need to continuously bear the scouring, corrosion and periodical thermal stress effects of high-temperature steam or fuel gas, so that extremely high requirements are put on compactness, forming quality and tissue stability of the welding joint of the insertion pipe and the transition section, and the quality defect of the welding joint can directly lead to medium leakage and structural failure, thereby causing equipment failure and even safety accidents. In the prior art, the welding operation of the insertion pipe and the transition section is mostly completed by adopting welding modes such as argon arc welding and the like. In the argon arc welding process, the back of the welding line is easy to contact with air to generate oxidation reaction, so that the forming quality and mechanical property of the welding line are affected, and therefore, in order to ensure the forming quality of the back of the welding line, argon protection is usually required to be implemented on the back of the welding line in the welding process, and the air is isolated by the argon, so that the defects of oxidization, air holes and slag inclusion on the back of the welding line are avoided. However, because the structure of the cannula has the characteristics of long and narrow inner space and closed cavity, the traditional back argon protection mode is mostly dependent on temporary plugging, hose insertion or empirical operation of operators, and a stable and uniform protective gas environment is difficult to form in the cannula, so that the consistency of welding quality is poor, and the severe requirements of high Wen Dongli equipment on welding joints cannot be met. The traditional back argon mode has the outstanding problems that firstly, argon is conveyed by adopting a mode of single-point air supply or simple hose insertion, argon is difficult to ensure even distribution in the cannula, partial shielding gas concentration is insufficient or gas turbulence phenomenon is easy to occur, quality defects such as oxidation, grain coarsening and air holes are caused on the back surface of a welding seam, compactness and tissue stability of a welding joint are seriously affected, secondly, the traditional back argon mode lacks a reliable fixing and sealing structure, in the welding process, the back argon protection failure is easily caused by shielding gas leakage, tool looseness or position offset, the back argon tool is mostly specially designed, universality among different specifications and different sizes of cannulas is poor, repeated adjustment is needed for the tool when the specifications of the cannulas are replaced each time, workload of operators is increased, production efficiency of welding operation is seriously affected, and meanwhile, stability of welding quality of the cannulas with different batches and different specifications is difficult to ensure. Disclosure of Invention The invention aims to solve the problems of poor welding quality consistency, unstable protection effect, poor tooling universality and low production efficiency in the welding back argon protection of a cannula and a transition section in the prior art, and further provides a cannula welding piece penetrating type inner cavity back welding protection device, a manufacturing method and a using method. The application adopts the following technical scheme for solving the problems: A penetrating type inner cavity back welding protection device of an insertion pipe welding piece comprises a protection barrel, a plurality of barrel fixing pieces and a plurality of protection gas conveying pipes; The protection barrel is circular barrel, and a plurality of barrel mounting along radial equipartition setting is on the protection barrel lateral wall, and