The invention concerns a protector ring which serves to protect the machined ends of tubes which have to be welded together against damage

05 in transport or storage. The protector ring is placed on the inside of the tube. In this stage the ring is open and the ends fit over each other. To protect the welding edge the ring is bent outwards in an angle of about 140 degrees. The end of the bent part is conical and rests against the butt end of the tube. This way a hollow space is

10 created around the narrow and vulnerable welding edge. If the tube is hit on the butt end the protector ring could be damaged but will deform without touching the vulnerable welding edge. The protector ring can be attached into the tube in different ways. One end is provided with a long inward curved tongue which, when pressed flat, pushes against a

15 hook on the other end and tightens the protector ring in the tube. For large diameters the protector ring can be equipped on both ends with a hook in between which a zig-zag spring is positioned. A third possibility is to make use of slits in one end in which a tongue of the other end fits and where in the circumference of the protector ring

20 resilient lips are formed which press against the interior of the tube. It is known to protect tube ends with an internal ring with a flange which reaches beyond the welding edge and whereby a tongue (welded onto the ring) clamps the ring through deforming. It has been found that this type of ring provides hardly any

25 protection. It is of the utmost importance that the welding edge, mostly having a width of no more than one or one and a half millimeter, fits without obstructions clearly and precisely to the welding edge of the connecting tube. An obstruction can cause welding beads on the inside of the tube. It is also possible that when automatic welding

30 machines are used obstructions cause melting of the whole welding edge requiring costly repairs. In most cases protectors have openings between ring ends which allows for possible damage to the welding edge.

The invention provides a protector ring which creates a hollow space

* 35 around the welding edge preventing nearly all damage in case of bumping. _j. Furthermore the invention provides for overlapping ring ends to protect

* the entire butt end of the tube. The invention concerns also diverse lips and hooks which are formed out of the material of the ring.

The invention will be described with the help of the drawings.

Fig. 1 shows a eras section of the tube end with the protector ring.

Fig. 2 shows view according arrow I. Fig. 3 shows view according arrow II.

Fig. 4 shows view according arrow I using a spring _*

Fig. 5 shows view according arrow III.

Fig. 6 shows in perspective the system with resilient lips.

In Fig. 1 the to be protected tube is indicated with (1). In tube (1) is attached protector ring (2). Protector ring (2) fits with a cylindrical part (3) in tube (1). Attached to the cylindrical part (3) is a flange (4) which is bent outwards with an angle (5) further than 90 degrees in such a way that the flange (4) makes an angle of about 145 degrees to the cylindrical part (3). When the protector ring (2) is placed into the tube CD flange (4) will rest against the machined surface (6). This way a hollow space (7) is created. The welding edge (8) is thus completely protected by the bent flange C4). When, for instance during transport the tube CD is bumped the protector ring has to be considerably dented before the welding edge (8) iε damaged. To prevent damaging the tube CD through an opening in the protector ring C2) the ends (9) and CIO) are made overlapping. For this purpose the end CIO) is bent outwards slightly and flange C4) is made wider.

In view of the often large diameters and tolerances of tube CD it is necessary to provide the protector ring (2) with a fastener which will clamp the protector ring C2) In tube CD. In Fig. 2 and 3 is a long tongue C l) cut at end CIO) which is bent towards the center of tube CD. Tongue (11) carries a back bent part (12) which fits against hook C13) which in turn is cut and bent out of end C9). This hook C13) reaches through opening C14) which is created by cutting tongue Cll) and which cares for fitting the two ends C9) and C O). By pressing tongue Cll) flat the protector ring C2) will be spread and locked into the tube CD. Fig. 4 and 5 show a variant where a zig-zag spring C15) is positioned between hook C13) and a hook 16) which is formed by bending the end of opening C17) at the end CIO). By compressing spring C15) more or less it is possible to adjust the force of the spring in degrees.

Fig. 6 shows a variant whereby slits 18) are cut out of end (9) into which tongue C19) fits. By selecting anyone of the slits (18) the protector ring C2) can be set to the diameter of the tube (1) which facilitates the protector ring C2) to be placed into the tube (1). Cut-αut resilient lips C20) take care of the locking attachment in tube CD.