Hatch for the opening and closing of pressurised pipes, in particular for the opening and closing of branch pipes for the introduction of pipe cleaning and inspection apparatus

Abstract

A closing system for pressurized pipes, includes an annular supporting structure, designed to be secured to one end of the pipe, a closing hatch mounted on the annular support, and elements for locking the hatch including a locking ring inserted into an annular cavity in the support to lock the hatch, wherein the inside edge of the hatch is tapered to form an inclined wall for coupling to a corresponding inclined wall in the annular support. The collapsible ring includes a number of sectors, one of which is fixed and integral with the hatch, while the others are hinged to the adjacent sectors, so that they can rotate on a plane parallel with the hatch until they exit from the annular seating and allow the hatch to open. The hatch is opened and closed simply by rotating it around a hinge.

Description

This invention will be better understood from the detailed description that follows, provided by way of example but not of limitation, by reference to the annexed figures wherein:

FIG. 1 is a front view of the hatch according to the invention in the closed position;

FIG. 2 is a cross-section along line E-E in FIG. 1;

FIG. 3 is a view of the hatch in the open position;

FIG. 4 is a cross-section along line F-F in FIG. 3;

FIGS. 5 and 6 are front views of the hatch according to the invention, during two successive locking stages;

FIGS. 7 and 8 are further views of the hatch, in perspective view and cross-section respectively.

Claims

1) Closing system for pressurised pipes, of the type comprising an annular supporting structure (1), to be welded or secured to one end of the pipe, a closing hatch (2) mounted on said annular support, and means designed to lock said hatch in the closing position, said means consisting of a locking ring (7) inserted into an annular cavity (8) in said support to lock the hatch, characterised in that the inside edge (17) of said hatch is tapered to form an inclined wall designed to couple to a corresponding inclined wall in said annular support.

2) Closing system for pipes as claimed in claim 1, characterised in that a seal (18) on said inclined wall (17) of the hatch (2) or on said corresponding inclined wall of the annular support is compressed when the hatch is closed.

3) Closing system as claimed in claim 1, characterised in that said locking means consist of a collapsible ring (7) mounted on the outer wall of the hatch (2) and designed to be inserted into an annular groove (8) in the support (1).

4) Closing system as claimed in claim 3, characterised in that said collapsible ring (7) consists of a number of sectors, one of which (9) is fixed and integral with the hatch (2), while the others are hinged to the adjacent sectors, so that they can rotate on a plane parallel with the hatch (2) until they exit from said annular seating (8) and allow the hatch to open.

5) Closing system as claimed in claim 4, characterised in that said fixed sector (9) is positioned close to the hinge of the hatch (2).

6) Closing system as claimed in claim 5, wherein one or more annular sectors (10, 11) are hinged at either end to said fixed sector (9), the last two sectors (10, 11) being hinged to an articulated system consisting of two rods or connecting rods (13, 14) hinged together and to said end sectors, one of said rods being integral with an operating lever (15) designed to control the movements of said sectors between a position in which they are arranged in said seating (8) to form a continuous ring (7), and a position in which they exit completely from said seating.