FI60432C - ROERFOERBINDNING - Google Patents

Description

. rRl M1. ADVERTISEMENT PUBLICATION, LJ UTLAGG NIN GSSKRI FT 60432 C Patent issued 11 01 1902 ^ Patent eeddelat 'SV ^ (51) Kv.lk?/lnt.CI.3 F 16 L 47/00 FINLAND — FINLAND (21) Pttunttlhakumut - Pitununseknlng 1233 7 ^ (22) Hakemliptlvi - Anteknlng * dt (2 3 - 0U .7 ^ '' (23) AlkupUvt — GIKlfhuudag 23.0U.

(11) Became Stuck - Bllvlt offentllg 28.10.7 ^

Patent and registry holders .... ...... .........

_ ^ \, (44) N »ht» »lktlpwoo and kuLfulkalsun pvm. -

Patent- och registrerttyrelsen 'Aitkin utlagd och utUkriftun publkmd 30.09.81 (32) (33) (31) Pyydetty atuolkau * - Begird prlorltet 2 7.01 *. 7 3

Netherlands-Nederländerna (NL) 7305985 (71) Wavin B.V. , 251, Handel, Zwolle, Netherlands-Nederlanderna (NL) (72) Paul Christiaan Herman van den Beld, Hardenberg, Netherlands-Nederland (NL) (7 ^) Berggren Oy Ab (5U) Pipe connection - Rörförbindning

The invention relates to a pipe connection comprising at least one thermoplastic sleeve part and a male pipe part sealed against the inner side of the sleeve part.

Pipe connections in which a male pipe part made of polyethylene is sealed to the inner side of a sleeve or female pipe part are known. To achieve a proper connection, the male tube section should be threaded into the female tube section in a central position. For this purpose, devices are provided with gripping means for achieving a central position with respect to the female tube part. However, the interlocking devices cannot receive very large outward forces and thus cannot be used when using auxiliary parts made of synthetic material which are short and / or conical. In this case, the expanding effect of the auxiliary parts would place too much strain on the centering members and / or they would not be able to keep the female tube sections in a central position when the male tube sections are installed. Such auxiliaries must also be connected manually and a lot of skill is required to achieve a well-centralized installation. Reliability also requires that the joint be tested, which adversely increases costs.

60432

Dutch patent publication 102 520 discloses a pipe connection having both a female part and a male part, the inner side of which is formed as a double sleeve5 of the female part, which is thermally connected to the corresponding outer side of the male part. The sleeves are relatively small, and when the gripping member should be able to be locked simultaneously at both ends of the sleeve, there are difficulties with centering. The difficulties are particularly striking in the embodiments shown in Figures 3 and 4 of the above-mentioned patent publication, in which the outer surface of the female part or the sleeve is curved. In such cases, there are great difficulties with the reliable operation of the gripping member, especially since the outer surfaces of the sleeves cannot be made exactly identical at the manufacturing stage.

In practice, therefore, cracks have appeared in the sleeve, which is a very bad drawback, especially if the pipe is a polyethylene pipe intended for transporting natural gas.

Other types of pipe joints, the parts of which are not thermally connected to each other, are described in U.S. Pat. No. 2,480,283 and French Pat. No. 1,115,104.

The object of the invention is to provide a pipe connection of said type which does not have the disadvantages described and in which a suitable centering of the gripping members relative to the sleeve part is always guaranteed.

This object is achieved by an arrangement characterized in that the outer surface of the sleeve part has centering projections and bearing surfaces extending longitudinally from the sleeve part to the nearest free end of the sleeve part for centering the gripping members to keep the male-tube part in the centered position.

With such centering projections and bearing surfaces, it is possible to mount the gripping members in the correct position with respect to the opening of the sleeve part. As a result, no skilled labor is required to form such pipe joints.

3,60432

The abutment surface of the centering projections, i.e. the abutment edge, is preferably substantially perpendicular to the longitudinal axis of the core part.

In order to attach the gripping members, the cross-sectional profile of the outer side of the cylindrical or frustoconical bearing surfaces may preferably include transverse or helical ridges. The gripping members can then be mounted in an advantageous manner, for example by means of two fasteners on the outside of the sleeve part.

The sleeve and male tube section is preferably made of polyolefins such as homopolymers and copolymers of ethylene, propylene, butene and higher olefins.

The invention will now be described with reference to the accompanying drawings, which show an embodiment of the invention.

^ 60432

Fig. 1 shows a longitudinal section of a pipe joint, the female pipe part of which forms a double sleeve, the support centering surfaces having different shapes at both ends thereof; Figure 2 shows a subtraction piece; Figure 3 shows a bend; Fig. 1 shows a closure cover; Fig. 5 shows a branch piece, and Fig. 6 shows a T-piece.

Figure 1 shows a sealed pipe joint comprising a female pipe section in the form of a double sleeve 1 and a male pipe section 2, both made of polyethylene. The outer side 5 of the male pipe part 2 and the inner side 6 of the female pipe part, as a double sleeve 1 against the surface 5, are connected to each other by means of a sealed connection 7. To ensure the correct installation method, between the male pipe part 2 and the female pipe part, the double sleeve 1 is provided on its inner side with an internal central support collar 8.

In order to allow a well-centered setting of the male tube part 2 in the female part 1, the gripping members should be placed outside the male tube part 2 at the desired distance from the opening.

In order to perform the latter function, the female tube part includes on its outer side centering support projections 9 »which in the present case form a support edge. Accordingly, the support surfaces of the centering support projections, as a support edge 9, are substantially perpendicular to the longitudinal axis of the male tube section to ensure ever better centering.

In order to ensure proper placement of the gripping members, e.g. on the outer side of the female tube part, the outer circumference 3 of which increases towards the center, The maximum outer circumferential length is preferably at the opening ^ of the female tube part.

It is advantageous to provide the bearing surfaces 10, 10 'with helical ridges 11, or transverse ridges 12, the helical ridges 11 allowing the gripping member to be screwed onto the bearing surface until it rests against the support edge 9.

5,60432

When using a frustoconical bearing surface, it is obviously impossible to fasten the gripping member by twisting and thus it is fixed by pressing the frustoconical bearing surface 10 '. The transverse ridges 12 are preferably formed on this bearing surface to hold the gripping member in a suitable position.

The double sleeve 1 is preferably barrel-shaped in appearance with a radius of curvature of 6 to 12 times and preferably 8 to 10 times the outer diameter of the male tube part, the total length of the double sleeve being equal to the outer diameter of the male tube part.

These dimensions have been found to be very advantageous in the manufacture of such a sleeve by injection molding, as shrinkage symptoms result in all sorts of changes to the final product.

With the correct selection of these dimensions, it is possible to produce a double sleeve by injection molding, in which the conical shape of the two opposite openings 4 does not change, and the distance between the openings is chosen to be the same as the outer diameter of the male tube part.

The inner surfaces 6 ', 6 of the sleeve form a truncated cone-shaped surface, the forming lines of which are at an angle of 0-2.5 ° and preferably 1-2.5 ° with respect to the longitudinal axis of the pipe section, the truncated cone-shaped surface having the largest outer circumferential diameter at the opening 4.

In this way, an excellent tight connection can be obtained when the male pipe part 2 is threaded into the female pipe part 1.

The 'bearing surface 10' may also, as mentioned above, be in the shape of a truncated cone, with its largest outer circumferential dimension at the opening 4. In this way, the stresses caused by the sealing pressure on the female pipe part are damped.

As shown in the drawing, the bearing surface 10 is located between the support edge 9 and the opening of the female tube part. Obviously, this is not necessary. It is thus possible, for example, to form a support edge 9 at a greater distance from the opening 4 and the bearing surface 10, 10 'can correspondingly terminate at a distance from the opening 4.

6 60432

Figure 2 shows a subtractor 12 which can act as a female tube part.

This female tube part 12 is again provided with a support edge 9 and a cylindrical bearing surface 10 extending in the vicinity of the opening 4 of the female tube part.

The bend according to Fig. 3 has a support edge 9 at a small distance from the opening and the free end of the cylindrical bearing surface 10 terminates at the opening 4.

The closure cover shown in Fig. 4 is provided with a support edge 9 with bearing ribs 10 with transverse ridges 12 for attaching the gripping members.

The branch piece shown in Fig. 5 can also act as a saddle part with a support edge 9 in the vicinity of the opening, while the frustoconical surface 10 extends from the opening until the support edge 9 joins it.

The T-piece shown in Fig. 6 is provided at several points with support edges 9a and cylindrical bearing surfaces 10 and cut-cone bearing surfaces 10 ', respectively.

Claims (3)

7 60432 1. The reinforcement of the inner material and the sleeve (1) of the thermoplastic and the sleeve (2), which may be provided with the inserts (6, 6 ') of the sleeve, the transverse means of the sleeve (1) and the centering sleeve (9) and lagerytor (10, 10 '), vilka sträcker sig i slesdelens längdriktning frän utsprängen (9) account slesdelens närmast belägna fria ände, vilka utsprdng (9) sleeve (1). A pipe connection comprising at least one thermoplastic case part (1) and a male pipe part (2) sealed against the inner side (6, 6 ') of the case part, characterized in that the outer surface of the sleeve part (1) has centering projections (9) and bearing surfaces ( 10, 10 ') extending in the longitudinal direction of the core part from the protrusion (9) to the nearest free end of the core part, which protrusions (9) are intended for centering the gripping members to keep the male tube part (2) in a centered position with respect to the core part (1). 2. The method of claim 1, which is based on the centralization (9) of the invention. Pipe connection according to Claim 1, characterized in that the centering projections (9) form a stop edge. Pipe connection according to Claim 1 or 2, characterized in that the abutment surface of the centering projections (9), i.e. the abutment edge, is substantially perpendicular to the longitudinal axis of the sleeve part (1). ^. Pipe connection according to one of the preceding claims, characterized in that the cross-sectional profile of the outer side of the cylindrical or frustoconical bearing surfaces (10, 10 ') preferably comprises transverse or helical ridges (11, 12). 3. A method according to claims 1 or 2, which comprises a central locking system (9) or an annealing device which is of interest to the core (1) of the central axis (1).