CN-122016191-A - Pressure test connection method for special-shaped thin-wall pipeline

CN122016191ACN 122016191 ACN122016191 ACN 122016191ACN-122016191-A

Abstract

The invention relates to the technical field of pipeline pressure test and discloses a special-shaped thin-wall pipeline pressure test connection method which is realized based on a special tool comprising a 匚 -shaped tool main body, a communication joint and a sealing joint. The invention solves the difficult problem of pressure test connection of the special-shaped thin-wall pipeline without the screwed pipe joint, realizes accurate positioning and reliable sealing pressure test effect by the cooperative cooperation of the tool core structure and the method steps, does not need to damage the pipeline structure, has high operation efficiency and strong suitability, can meet the high precision requirement of maintaining the pressure for 120 minutes under the pressure of 1.5MPa, and is suitable for the airtight test of similar pipelines in the fields of aerospace, machinery and the like.

Inventors

REN GUANGHAO
ZOU CHUNGAI
ZHENG NAN

Assignees

贵州坤元动力科技有限责任公司

Dates

Publication Date: 20260512
Application Date: 20251223

Claims (5)

1. A pressure test connection method for a special-shaped thin-wall pipeline is characterized by adopting a special tool, wherein the special tool comprises a 匚 -shaped tool main body, a communication joint and a sealing joint, coaxial through holes are formed in the upper end and the lower end of the 匚 -shaped tool main body in a penetrating mode, the through holes comprise an upper end through hole and a lower end through hole, the lower end through hole is a conical positioning hole, the inner wall of the conical positioning hole is matched with the peripheral outline of a pipe joint of the special-shaped thin-wall pipeline, the communication joint and the sealing joint are coaxially corresponding to the pipe joint, the communication joint and the pipe joint are communicated through a rubber gasket with holes, the sealing joint and the pipe joint are sealed through a rubber gasket without holes, and annular limiting tables are arranged at the bottom ends of the communication joint and the sealing joint, and the method comprises the following steps: the method comprises the steps of firstly, preprocessing, namely cleaning a 匚 -shaped tool main body, a communicating joint, a sealing joint, a rubber pad with holes and a rubber pad without holes, and meanwhile cleaning a pipe joint of a special-shaped thin-wall pipeline, and confirming that all parts are not damaged and remain impurities; Positioning and mounting, namely fixing two sets of 匚 -shaped tool main bodies on a test platform, adjusting the distance between the two sets of tools according to the length of the special-shaped thin-wall pipeline, respectively embedding pipe joints at two ends of the special-shaped thin-wall pipeline into corresponding conical positioning holes, and realizing coaxial positioning through the fit between the inner walls of the conical positioning holes and the peripheries of the pipe joints; The third step of sealing assembly, namely placing a rubber pad with holes in an annular limiting table of a communicating joint, placing a rubber pad without holes in the annular limiting table of a sealing joint, screwing the communicating joint and the sealing joint into an upper end through hole of a 匚 -shaped tool main body through threaded fit respectively, screwing the rubber pad with holes to tightly attach to the end face of the pipe joint, conducting the pipe joint with the communicating joint through the rubber pad with holes, and fully covering the end face of the pipe joint by the rubber pad without holes to tightly attach to form a sealed cavity; Step four, pressure test, namely butting an air pipe of the pressure test equipment with a communication joint, gradually boosting the pressure to a preset pressure test pressure in a special-shaped thin-wall pipeline, maintaining the pressure for a preset time and carrying out leak detection; and fifthly, releasing pressure, ending, releasing pressure according to a specified speed, disassembling the tool, taking out the special-shaped thin-wall pipeline, cleaning all parts and storing.
2. The method for pressure test connection of a special-shaped thin-wall pipeline according to claim 1, wherein in the second step, the pipe joint is positioned in a fitting way through the wall of the groove after being placed in the conical hole, and the fitting state of the pipe joint and the sealing assembly is observed through the opening of the 匚 -shaped tool main body.
3. The method for pressure test connection of special-shaped thin-wall pipelines according to claim 2, wherein in the third step, a torque wrench is used for controlling the screwing of the positioning joint, and the screwing torque is 15-20N And m, the compression amount of the rubber pad is 1/3-1/2 of the thickness of the rubber pad.
4. The pressure test connection method for the special-shaped thin-wall pipeline according to claim 3, wherein in the fourth step, the preset pressure test pressure is 1.5MPa, the pressure maintaining time is 120 minutes, the sectional pressure increasing rate is not more than 0.3MPa/min, and the pressure is stabilized for 3-5 minutes every time the pressure is increased by 0.3 MPa.
5. The method for pressure test connection of a special-shaped thin-wall pipeline according to claim 4, wherein in the fourth step, the pressure release rate is not more than 0.2MPa/min, and the key sealing part is smeared with soap liquid for leak detection in the pressure test process.

Description

Pressure test connection method for special-shaped thin-wall pipeline Technical Field The invention relates to the technical field of pressure test of pipelines, in particular to a pressure test connection method of a special-shaped thin-wall pipeline. Background In the fields of aerospace, mechanical manufacturing and the like, special-shaped thin-wall pipelines are often used in key systems such as cooling, medium conveying and the like due to the advantages of compact structure, light weight, strong space adaptability and the like. The air tightness of the pipeline directly determines the operation safety and reliability of the whole equipment, so that the operation safety and reliability of the whole equipment are detected through a strict pressure test, and the high-precision standard of 120 minutes of air tightness of the pressure maintaining under the air pressure of 1.5MPa is even required to be achieved under part of scenes. At present, the mainstream connection mode of the pipeline air tightness test depends on the thread structure of a pipe joint, and the sealing connection is realized through the thread fit of the pipe joint and an extension pipe of pressure testing equipment. However, in practical application, part of the special-shaped thin-wall pipeline is limited by structural design, installation space or use function, and the pipe joint cannot be provided with threads, and is only of a smooth through hole structure, so that the traditional threaded connection mode cannot be applied at all. In the prior art, the replacement scheme for the threadless pipe joint is mainly strong glue bonding, namely, the extension pipe of the pressure testing device is fixedly sealed with the pipe joint through glue, but the mode has the obvious defects that the cleaning difficulty is extremely high after the glue is solidified, the surface of the pipe joint is extremely easy to scratch in the cleaning process, the integrity of a pipeline is damaged, the subsequent assembly and use of the pipeline are affected, meanwhile, the bonded connection structure cannot be reused, glue needs to be reapplied, solidification is waited for each test, the operation is complicated, and the test efficiency is extremely low. Disclosure of Invention The invention aims to provide a pressure test connection method for a special-shaped thin-wall pipeline, which aims to solve the technical problem that the special-shaped thin-wall pipeline without a screwed pipe joint is difficult to realize effective and reliable sealing connection with pressure test equipment in an airtight test. The special tool comprises a 匚 -shaped tool main body, a communicating joint and a sealing joint, wherein coaxial through holes are formed in the upper end and the lower end of the 匚 -shaped tool main body in a penetrating mode, the through holes comprise an upper end through hole and a lower end through hole, the lower end through hole is a conical locating hole, the inner wall of the conical locating hole is matched with the periphery outline of a pipe joint of the special-shaped thin-wall pipeline, the communicating joint and the sealing joint are coaxially corresponding to the pipe joint, the communicating joint and the pipe joint are communicated through a rubber gasket with holes, the sealing joint and the pipe joint are sealed through a rubber gasket without holes, annular limiting tables are arranged at the bottom ends of the communicating joint and the sealing joint, and the method comprises the following steps: the method comprises the steps of firstly, preprocessing, namely cleaning a 匚 -shaped tool main body, a communicating joint, a sealing joint, a rubber pad with holes and a rubber pad without holes, and meanwhile cleaning a pipe joint of a special-shaped thin-wall pipeline, and confirming that all parts are not damaged and remain impurities; Positioning and mounting, namely fixing two sets of 匚 -shaped tool main bodies on a test platform, adjusting the distance between the two sets of tools according to the length of the special-shaped thin-wall pipeline, respectively embedding pipe joints at two ends of the special-shaped thin-wall pipeline into corresponding conical positioning holes, and realizing coaxial positioning through the fit between the inner walls of the conical positioning holes and the peripheries of the pipe joints; The third step of sealing assembly, namely placing a rubber pad with holes in an annular limiting table of a communicating joint, placing a rubber pad without holes in the annular limiting table of a sealing joint, screwing the communicating joint and the sealing joint into an upper end through hole of a 匚 -shaped tool main body through threaded fit respectively, screwing the rubber pad with holes to tightly attach to the end face of the pipe joint, conducting the pipe joint with the communicating joint through the rubber pad with holes, and fully covering the end face of the pipe joint by the rubber pad withou