CN85205332U - Expanding section of pipeline sealed by the static pressure of fluid flowing in the pipeline - Google Patents

Abstract

The utility model relates to a self pressure sealed expanding section of a pipeline, comprising an outer cavity, a cutting sleeve, an inner cavity, a fastening bolt and a sealing ring. The cross section of the sealing ring is hollow, with openings at both ends; both ends with openings respectively abutted to the cavity walls of the inner and the outer cavities; the outside of the sealing ring is protected and positioned by the cutting sleeve, wherein, the hollow cavity is filled with the fluid flowing in the pipeline, and the pressed sealing is realized by the self static pressure of the fluid; when the pressure in the system of the pipeline changes, the sealing pressure can be regulated automatically. The utility model has the advantages of small pipeline expanding section volume, compactness, simple structure, high compensation capability, safety and wide ranges of application.

Description

Expanding section of pipeline sealed by the static pressure of fluid flowing in the pipeline

The utility model relates to the technical field of pipe expansion compensator and seal for pipe joints.

Various metallic conduits all have the problem of expanding with heat and contract with cold, particularly, for the pipeline of carrying various hot fluids (for example steam, coal gas, deep fat and various chemical solutions etc.), because operating temperature is higher, thereby its swell increment is also bigger, this will play destruction to pipeline to producing huge axial tensile force on the pipeline.The home and abroad all is to adopt expansion appliance to solve this problem in piping design and construction at present, and the pipe expansion compensator that they adopted has following several types:

(1) bend pipe compensator.This is to insert one section bend pipe every certain distance on pipeline, and L shaped, the Z-shaped and ㄇ shape (its schematic representation is seen Fig. 1, Fig. 2, Fig. 3 respectively) of having that the shape of bend pipe is common etc. are several.Though the bend pipe compensator is easily manufactured, boundary dimension and floor space are all bigger, and not only investment is big, and owing to insert so many bend pipes in pipeline, also can enlarge markedly fluid in ducted flow resistance.

(2) corrugated expansion joint.The structure of this expansion appliance as shown in Figure 4, though little, the compact structure of its volume; But compensation ability is little, and each node has only 10 to 20 millimeters extending amount.Generally speaking, corrugated expansion joint only is suitable for using on large diameter pipeline, makes the bellows compression behind the pipe expansion, so its stress is very big; For large diameter pipeline, bellows will form with the butt welding of hyperboloid annular wave plate, and this structure thermal shock resistance is relatively poor, usually can leak because of fatigue damage of materials.

(3) slip-type expansion joint.This is comparatively advanced at present a kind of expansion appliance, and its structure as shown in Figure 5.It is made up of parts such as exocoel, inner chamber, stuffing box and clamp flanges, and not only compact structure, floor space are little, and extending amount is also big than bellows.But because it is to adopt stuffing box and clamp flange to seal, needs periodical repair and change filler, otherwise tube fluid is easy to leak, and when the pipeline transverse bending is excessive, its interior Guan Yi is blocked by stuffing box and loses compensating action.Be generally and avoid interior pipe to be blocked by stuffing box, the guiding pipe support need be set at the two ends of compensator, so, just make the slip-type expansion joint structure become more complicated, therewith correspondingly, its machining required precision is also higher, installs also comparatively time-consuming.

The utility model is at the present existing shortcoming of known various pipe expansion compensators, a kind of self-pressure-sealed pipeline expansion joint has been proposed, it is made up of parts such as inner chamber (pipe promptly), exocoel (being outer tube), seal ring, cutting ferrule and clamping bolts, the cross section of seal ring is a hollow, it can be ducted fluid and fills, utilize the pascal's principle of incompressible fluid, make seal ring its outer wall under the static pressure of fluid itself fit with chamber, inside and outside chamber wall and seal.Its advantage of self-pressure-sealed pipeline expansion joint provided by the utility model is: (1) volume is little, in light weight, its weight only be identical bore slip-type expansion joint 75%; (2) simple in structure, cost is low, its cost only be identical bore slip-type expansion joint 80%; (3) compensation ability (being extending amount) is big, generally can reach 250～800 millimeters; (4) wide adaptability is suitable to the pipeline of large and small bore, and internal stress is little, and is safe and reliable; (5) installation, maintenance is also very convenient, during use, allows transverse bending distortion, and whole slip joint can have the degrees of freedom of 2 ° of distortion and not influence its compensation ability and also can not leak.

Self-pressure-sealed pipeline expansion joint provided by the utility model has two types at unidirectional joint and two-way joint, and its surface structure is respectively as Fig. 6 a, b; Shown in Fig. 7 a, the b, wherein a is plan view (being the figure of radially projecting); B is side view (being axis projection figure).(1) is exocoel in Fig. 6 and Fig. 7; (2) be cutting ferrule, seal ring promptly is in the cutting ferrule; (3) be inner chamber; (4) be clamping bolt.Two-way joint is with the difference between the unidirectional joint: it has two inner chambers, cutting ferrule and seal rings, is placed in the exocoel two ends symmetrically, and its compensation ability is bigger than unidirectional joint.

Self-pressure-sealed pipeline expansion joint key provided by the utility model is that the seal for pipe joints mode that it adopts is different with prior art.The seal ring of O type or rectangular cross section is adopted in common seal for pipe joints more, relies on exterior mechanical pressure, promptly with flange and fastening piece seal ring is compressed to seal.This sealing means is not too reliable, and fastening piece was installed pine or tension, all leaks easily.Its cross section of self-pressure-sealed circle that the utility model adopted is the structure of hollow and both ends open, during use, without exterior mechanical pressure, but allow in the cavity in the fluid-filled seal ring, rely on the static pressure of fluid self to make the seal ring two ends be fitted in the sealing that realizes inside and outside chamber junction point on the wall of chamber, inside and outside chamber.Though self-pressure-sealed circle outside is equipped with cutting ferrule, cutting ferrule be protection seal ring and effect that seal ring is located, though cutting ferrule be clipped on the wall of inside and outside chamber with clamping bolt, yet seal ring is not applied great mechanical pressure.In addition, whenever always the pressure with fluid in the pipeline is equal owing to the pressure in the self-pressure-sealed circle, and promptly when the pipe-line system pressure change, the sealing load of pipeline is can be self-regulating, so this self-pressure-sealed mode is very safe and reliable.

The self-pressure-sealed circle that the utility model adopted and following three kinds of different design proposals are arranged with its corresponding cutting ferrule and outer-cavity structure, embodiment is respectively shown in Fig. 8～10.Three embodiments' common ground is: on exocoel (1) outer wall fluted (6), cutting ferrule (2) one ends just are inserted in the groove, seal ring (5) cross section is hollow and both ends open, the two ends of its opening are attached to respectively on the chamber wall of inner chamber (3) and exocoel, opening direction is facing to several apertures of opening on gap between the inside and outside chamber or the outer chamber wall end, and its outer cause cutting ferrule surrounds and the location.Institute's difference then is between three embodiments: the contacted end afterbody of self-pressure-sealed circle among (1) Fig. 8 and Figure 10 and internal chamber wall is provided with boss (7), this boss matches with the sunk part of cutting ferrule, prevent that self-pressure-sealed circle is subjected to displacement when inner chamber moves, and the self-pressure-sealed circle among Fig. 9 leans on the side of internal chamber wall one end that boss (7 ') is arranged, and the boss bottom is by the location, end of exocoel.(2) fluid system enters with the space between the self-pressure-sealed circle madial wall by the exocoel end and is full of self-pressure-sealed circle among Fig. 8, and among Fig. 9 and Figure 10, several apertures (8) that fluid then has by (Figure 10) on exocoel end (Fig. 9) and the outer cavity wall barrier respectively enter and are full of self-pressure-sealed circle.

Claims (3)

1, a kind of pipeline expansion joint of being formed by exocoel (1), cutting ferrule (2), inner chamber (3), clamping bolt (4) and seal ring (5), it is characterized in that: a side of cutting ferrule is inserted in the groove (6) of outer chamber wall, opposite side closely contacts with internal chamber wall, and the cross section of the seal ring in the cutting ferrule is hollow and both ends open.

2, by the described pipeline expansion joint of claim 1, it is characterized in that the two ends of seal ring opening are attached to respectively on the chamber wall in inside and outside chamber, and opening direction is facing to several apertures of opening on gap between the inside and outside chamber or the outer chamber wall end.

3, by claim 1,2 described pipeline expansion joints, it is characterized in that outer chamber wall has two grooves, exocoel is connected with second cutting ferrule by the second groove, and two cutting ferrules are installed in two inner chambers and two seal rings the two ends of exocoel respectively.

Images