LT3294B - Sealing element for fixative assembling of pipes and fixative assembly-joint - Google Patents

Abstract

The capping (24) of a fixating sealing insert has a bump (30) on the side of the knife-edge, which is enclosed with two back surfaces (29, 31). When the spacer is put into the place of a muff (3), the enclosing end (1) is forced into a muff (3), radially compressing the spacer body. Then, two back surfaces (29, 31) make a knife-edge (30) angle in the middle, pointed into the muff bottom.This invention is used for fixing pipes made of cast iron with spheroidal graphite, which are under tension.

Description

The present invention relates to fixed assemblies between the end of one pipe end and the nipple. In particular, it is classified as a compact seal for fixed pipe assembly with a flanged end and a nipple. The gasket consists of a body and a hinged nozzle made of a rigid material and a plurality of locking inserts made of a solid material inserted into the nozzle and generally disposed in a cone having the same axis as the gasket and in the direction of the converging body; in addition, each liner protrudes from the gasket to its axis. During assembly between the tubes, using such spacers (e.g., DE 2226151, DE 2650776, EP 0433202), each locking liner is made of a solid material with a slight slope between the sleeve and the end of the sleeve. Such locking prevents axial movement in relation to one pipe, which could seal the joint and completely disassemble the pre-assembled pipeline under the action of axial dismantling forces exerted by the fluid contained in the tubing.

This type of locking system successfully replaces costly pipe jointing systems on the ground anchored as well as flanged bolted units.

However, such an attachment is only fully effective if it can guarantee a maximum distance from the end of the collar if the fluid pressure has stabilized. Therefore, it must be ensured that the rigid insertion of the sleeve end into the sleeve will not push the liner or gasket assembly into the bottom of the sleeve, into the annular sphere between it and the sleeve end.

The object of the invention is to provide a reliable gasket for a fixed pipe connection used for directly manufactured pipes.

The invention discloses an object of the specified type, i.e. this gasket is characterized in that the head or the outer portion of each liner has a body-side protrusion for supporting the liner in the process of inserting the cap end into the nipple, furthermore, this protrusion has a sharp edge and bounded by two posterior surfaces, in place in the nipple, and the cap end is inserted into it rigidly by radially compressing the body of the gasket, the two posterior surfaces forming an angle with each other near the sharp edge, at least for the large diameters of the cap end.

In addition, the two posterior surfaces form an angle directed to the bottom of the nipple, with various diameters of the cap at a tolerance range and at any position of insertion of the cap at a specified angle of less than 90 °. greater than 90 °, each insert has a plurality of mandibular engagement teeth disposed axially and radially to one another, each insert head having a surface radially inclined inwardly and axially outwardly in relation to the nipple, in addition to this the surface ends, preferably with rounding, the gasket having an inner sealing groove on the inlet side of the nipple in a radial position.

It is another object of the invention to provide a locking joint between the sleeve end and the sleeve having the above gasket, furthermore, the sleeve body is pressed radially between the sleeve and the sleeve end and its nozzle is housed in a sleeve coupling recessed by a bottom one of which (front) is almost radial, and the inner radial portion of each insert is provided for peripheral fixation of the cap end with the head resting on the bottom of the groove and, if necessary, the retaining wall on the nozzle entrance side.

In the aforesaid case, where the head of each insert has a surface inclined radially inwards and axially to the outside of the nipple, this surface ends, preferably, with rounding, preferably with the support wall of the nipple being at its entrance. opposite sides, have an outer radial part of the cone type so that the insert head rests almost on the joint and the bottom of the recess at large cap ends, while at the small cap ends it rests on both the bottom and the same rake part.

In another aspect of the invention, the assembly angle formed by the outer rear surface with the indicated front wall is smaller than the angle formed by the other rear surface with this wall.

Embodiments of the invention will now be described with reference to the drawings in which:

Figure -1.

Figure -2.

Figures -3 and 4.

shows axial sections of a sleeve having a gasket and a cap formed for insertion into this sleeve according to the invention;

illustrates an incoming capture assembly according to the invention;

shows a larger scale position of the gasket inserts in the process of inserting the cap, respectively (axial section) for the maximum and minimum diameters of this cap, and the elastic portion of the spacer according to the invention is not shown for clarity of the drawing;

Figure -5-8. shows the assembly fixation according to the invention for decreasing diameter of the cap end.

Fig. the bulging end 1 of the first tube 2 and the suction 3 of the second tube 4, in addition, this nipple has an intermediate 5. The three elements 1, 3 and 5 are rotational bodies around one and the same horizontal axis Χ-Χ. Two tubes made, for example, of a spire with spheroidal graphite.

The sheath end 1 has an outer cylindrical surface clipped from the outside 6 at the end of the tube.

The sleeve 3 has an inlet rib 7, then successively from end to front, that is, from this edge to the bottom of the sleeve, a relatively deep coupling groove 8, a less deep spacer notch 9 and an inner protrusion 10 radially restricting this notch 9 , not as deep as the notch 9, and freely receiving the back 1 of the hood. Tolerance of fabrication end fabrication for a given inlet diameter and defects in its positioning (axial misalignment and angular misalignment) leads to the fact that in each half-plane of the axial section, the outer circumference of the circumferential end can be located between the positions corresponding to practically zero axial gap, and in a position corresponding to a maximum axial spacing with respect to the same edge. This is equivalent to the range of outer diameter of the cap end between the maximum and minimum size, ideally centered on the position of the cap, so we will continue to rely only on this diameter range.

As can be more clearly seen in Fig. 3, the sleeve groove 8 is delimited at the rear by an inner radial wall 12 slightly inclined relative to the vertical and an outer radial wall 13 inclined much more, in the embodiment shown, to about 45 °. The wall 13 is connected to the cylindrical bottom 14 of the groove 8, which in turn connects to the near radial wall 15 of the groove. The recess 9 has a cylindrical bottom 16 connected to the wall 15 and a radially arranged first annular projection 17.

The spacer 5 (Fig. 1) is a molded part of a flexible or rigid material, such as an elastomer, in which a series of clamping liners 18 are provided with a massive body 19 and an attachment protrusion 20 radially outwardly extending inwardly.

Her front butt protruding into

At rest, the posterior and outer profiles of the gasket are the same as the profiles 12 - 16 of the sleeve 3 surfaces. Gasket Inserting without significant deformation in the sleeve, in this case, there is a gap between it and the suction surfaces 12 - 14, the moment it is pressed against the surfaces 15 and 16, there is a free gap between the forward end 22 and the surface 17 of the curved body 19.

By the way:

- the inner surface 23 of the body 19 extends into a cone at the front from a diameter close to the inner diameter of the rib 7 to a diameter smaller than the smallest diameter of the outer circumference 1,

The growth 21 is radially oriented and is approximately between the same diameters as the inner surface 23 on the rear surface 19 of the body.

Each liner 18 (see Figures 1, 3 and 4) is in the radial plane, has an L-shaped shape and has an outer radial head 24 which is inserted into the protrusion 20, as well as a radial inner connecting end 25 which extends forward to a slight protrusion forming a sealing body surface 23 about half its length.

The head 24 (Figs. 3 and 4) has a rectangular shape and a trailing edge 26 at the rear which is almost parallel to the nipple surface 13 at rest.

The radially exterior head 24 has an edge 27, almost perpendicular to the preceding and connected to it by a rounding 28, and a forward edge having a protruding shape consisting of two parts: a radial outer part 29 forming an obtuse angle about 135 ° to the edge 27; sharp edges 30, and a radial inner portion 31 with a wide inner rounding having a center angle of about 90. The tangent edges of this rounding at level 30 form an angle with the projection 29 slightly over 90 °. This angle may also be less than 90 °.

The connecting end 25 is laterally delimited by two almost parallel ridges: the trailing edge 32, connected to the rounding 33 of the edge 26, and the leading edge 34, connected by a tangent to the rounding 31. The connecting end 25 terminates with four protrusions 35 . As will be explained later, the three protrusions 35 located posteriorly form the teeth for adhesion to the mandibular end, while the fourth protuberance 35 located forward, i.e. toward the bottom of the cuff, forms an impermeable protrusion limiting the penetration of the teeth into the mandibular end.

When the cap end 1 is inserted into the nipple 3, it bends the recess 21, then pushes forward the body 19, compressing it radially. Then the gasket tends to creep forward. This forms a contact between the sharp edge 30 of the liner 18 and the nipple surface 15 (see Figures 3 and 4) such that at any outer diameter of the outer wrap end during the latter insertion process, the sharp edge 30 will always protrude outwardly onto the liner. heads and are always against the surface 15.

This free support 30 - 15 prevents the liners from sliding radially inside the sleeve, outside the chamber, and, as a rule, protects them from deformation. As shown in Figures 3 and 4, this can go up to the position shown by the dotted dot line, thus providing security.

Furthermore, at normal pipe intervals, i.e., at the diameter of the spigot end of the interval and at the intended joint positions, and even outside such ranges, the pair 30 - 15 behaves as a single directional system, further increasing the reliability of the joint. In fact, the angle of inclination α between surfaces 29 and 15 remains smaller than the angle β between surfaces 31 and 15 (see Figures 3 and 4) such that the liner can easily enter chamber 8 (at the surface of nipple 14) when exposed. radial forces in this direction, but it is blocked if the direction of the radial forces changes.

It should be noted that the width of the joint end 25 is smaller than the radial clearance between the surface 16 and the collar end, in order to avoid any risk of the joint becoming jammed. In addition, it is understood that the support 30 - 15 is principally significant with large outer diameter of the enclosure, which increases the risk of intermediate movement (Fig. 8).

When the insertion end is completed and pressure is applied to the pipeline, the sheath ends are usually subjected to back forces. The inserts 18 limit such displacement as follows (see Figure 5-8).

When the outer diameter of the mandrel is maximized (radial zero spacing between the mandrel and the lip 7), its displacement pushes the rounding 28 of each insert into an angle formed by the mandrel surfaces 13 and 14 and the second tooth 35 engages the mandrel. This is determined by the deflection force 36 and the center of rotation of the insert 37. The design is such that the slope toward the radial force 36 is in the range between the lower limit at which the tooth can perforate the mandrel and the upper margin at risk of slipping at the tooth.

As the outer diameter of the mandrel decreases from its maximum diameter (Fig. 6), the insert head support to the sleeve is the same as before, but the two intermediate teeth 35, only the third tooth engages with the mandrel, which maintains the slope bending force 36 within the limits. , despite the large slope of the connection end liners.

As the outside diameter of the enclosure decreases, the rotation of the liners continues until the edge 26 contacts the surface of the nipple 13 (Fig. 7).

The center of rotation of the liners moves from point 37 to another point 38 closer to the X-X axis and slightly backward, allowing the bending force to remain within the required range, whereas without such a scheme it would go beyond these at one and the same end of the envelope. for diameter.

Finally, in the smaller range of outer diameter of the cap end (Fig. 8), the third tooth 35 is always adhered to the cap end, and the insert head rests two points in the groove 8, i. y. rounding 28-to-bottom 14, and rounding 33-to-surface 13. Again, the center of rotation 38 settles to guarantee a corresponding slope of force 36.

Such retention of the slope of force 36 by the double supports of the liner heads favors an increase in the allowable internal pressure in the duct, moreover, this pressure is proportional to the angle formed by the bending force with the radial direction. It has to be noted that this is achieved without the additional use of the insert tooth, which saves materials and reduces dimensions in the manufacture of the insert.

In all cases, the support 30 of the rib 30 to the surface 15, during the joining process, limits the maximum possible displacement of the cap by bringing the pipeline into service.

The smallest rear projection 35 on the inlet side of the nipple has a safety element for failing to insert the liners in their normal position. The rear protrusion 35, directed in the direction of the bottom of the nipple, acts as an anti-penetrating protrusion that provides pressure limitation at the contact of the cap having the smallest diameters with adjacent tooth teeth and thereby increasing the maximum allowable pressure.

The aperture 21 provides sealing with respect to the outer members, i. y. prevents the entry of external aggressive or corrosive elements into the lock zone. Due to its radial orientation, it cannot get under the liners during the joining process.

If necessary, the liners may be covered with electro-insulating materials such as ceramic.

Claims (10)

DEFINITION OF INVENTION 1.Sealing gasket for fixed pipe assembly between the end pipe 1 and the sleeve 3 having a body 19 and a gripping protrusion 20 of a rigid material and a plurality of locking inserts 18 of a solid material inserted into the protrusion and having the same cone the Χ-Χ axis as the intermediate and converging body 19, each liner forming a protrusion beyond the intermediate 5 along its axis, characterized in that the head 24 or the radial outer portion of each liner 18 has a protrusion on the body side that maintains the liners in the process of inserting the end into the nipple, the protrusion has a sharp edge 30 and is bounded by two posterior surfaces 29,31 such that when the gasket is in the nipple and the sheath is force applied to it by radially compressing the body of the gasket the edge 30 of the ribs facing the bottom of the nipple, and this the condition is satisfied, at least for large diameter ends of the enclosure. 2. Sealing gasket according to claim 1, characterized in that the two posterior surfaces 29,31 form an angle directed to the bottom of the nipple at any diameter of the cap end 1 within the permissible range and in any position by inserting the cap end into the cuff. Sealing gasket according to claim 1, characterized in that said angle is less than 90 °. Sealing gasket according to claim 1 or 2, characterized in that said angle is slightly over 90. Sealing gasket according to claims 1-4, characterized in that each insert 18 has a plurality of engagement teeth 35 disposed axially and radially to one another on the cap end 1. Sealing gasket according to claims 1-5, characterized in that the head 24 of each liner 18 has a surface 26 inclined radially inward and axially outwardly of the nipple, opposite to the projection 23-31. , this surface preferably ends with a rounding of 28.33. 7. Sealing gasket according to claims 1-6, characterized in that the gasket 5 has a noticeably radial inner gasket opening 21 on the inlet side of the nipple. 8.Fixed assembly of cap 1 and nipple 3 having spacer 5 according to claims 1-7, characterized in that the spacer body 19 is radially pressed between the nipple and the cap, its projection 20 being disposed in the nipple engagement channel 8 bounded by the bottom 14 with with two retaining walls 12-13,15, of which the first wall 15 is nearly radial, furthermore, the inner radial portion 25 of each insert 18 is formed so as to engage the head 24 at the periphery of the cap end, resting on the bottom 14 of the groove 8 and wall 12-13 on the entrance side of the nipple. 9. Assembled assembly according to Claim 8, characterized in that the spacer 5 corresponds to Claim 6, and the support wall 12-13 of the sleeve 3, located on its inlet side, has an outer conical radial portion 13 so that the head 24 of the inserts 18 is joining the portion 13 with the bottom 14 of the groove 8 at a large diameter of the cap 1 and, at small diameters of the cap, resting against the bottom 14 and the same portion of the slope 13. Assembled assembly according to Claim 8 or 9, characterized in that the angle of the collar 1 to any diameter within the permissible range and at any position of insertion of the collar into the collar is formed by the posterior outer surface 29 with the indicated front wall 15, is smaller than the angle formed by the latter with the other posterior surface 31.