NL192099C - Seal for a hatch cover of a vessel. - Google Patents

Description

1 192099

Seal for a hatch cover of a vessel

The invention relates to a seal for a hatch cover of a vessel, consisting of a seal made of elastic material such as rubber and attached to the edges of the hatch cover, which is pressed against the top of the hatch head when the hatch cover is closed. hatch cover seal, which cross-sectional seal is equipped with two cavities located one above the other, the lower cavity of which is smaller and is located in the downwardly narrowed bottom of the seal and the other cavity is in the horizontal center of the seal fitted.

Such a seal is known from the German Offenlegungsschrift 1,750,317.

In this known sealing, the upper cavity is horseshoe-shaped, in which cavity a vertically oriented back protrudes. The bottom cavity is circular. When pressure is applied in vertical direction, the wall surrounding the horseshoe-shaped opening deforms and the seal is pressed further into the groove until the back rests against the top wall of the horseshoe-shaped opening. With continued pressure exertion, the lower cavity is pressed shut and the back pressed against the upper surface of the sealing groove with increasing force. The selected shape results in the avoidance of a lateral contact of the seal against the side walls of the sealing groove. The axial compression of the seal almost exclusively results in a surface pressure on the top and bottom surfaces of the sealing groove.

The object of the invention is to provide a seal of the above-described type with a different force / indentation characteristic, namely as shown in figure 1, whereby a substantially constant pressure force is obtained over a relatively large indentation area.

This object is achieved according to the invention in that the cavities are wide and kidney-shaped with a convex side facing the narrowed underside of the seal, while two additional cavities are further arranged at the same vertical height between the cavities.

By this design it is achieved that the lower cavity is first pressed shut at an initial pressing force, after which the compression of the seal increases with substantially constant pressing force per meter of sealing profile length. An additional advantage is the spreading force produced in the seal under axial pressure, which presses the seal against the side walls of the groove in which the seal is received, thereby reducing the chance of the sealing profile tilting away from the receiving groove.

It is noted that a hatch cover seal with the same indentation characteristic as Figure 1 is known from US Patent 3,763,595. This characteristic is obtained with a seal consisting of a large number of walls with intermediate chambers, which must therefore necessarily be made of a very flexible, rather soft elastomeric material (rubber). During use, the problem arises here that the seal no longer fully returns to its original shape after compression, but partly retains the pressed shape. The life of such a seal is therefore short.

An embodiment of the seal according to the invention is further elucidated with reference to the drawing. Herein: figure 1 shows a curve of the contact pressure per m sealing profile as a function of the indentation in mm; Figure 2 shows a cross-sectional seal based on the invention.

The hatch cover sealing construction for a vessel consists of a rubber made seal attached to the hatch cover edges, which is pressed against the top of the hatch cover when the hatch cover is closed, sealing the hatch cover. The seal 1 has two cavities 2, 3 above each other in cross section: the lower cavity 2 is smaller and located in the downwardly facing narrow top of the seal 1, and the other cavity 3 is in the horizontal center of the seal 1. The cavities 2, 3 are wide and downwardly bent and kidney-shaped.

Between the cavities 2, 3 there are two cavities 4 which are located on the same horizontal level. An arrowhead-shaped polygon 5 can be drawn around the cavities 4.

An ideal so-called sliding cover for the hatch cover behaves according to the curve in figure 1. When the seal is initially pressurized, the force increases as quickly as possible to the level 6 required to obtain a watertight seal. When compressing the seal further, it is advantageous that the force required thereby remains constant for as long as possible. The point where the curve shows a steep increase in force forms the upper limit of the usable compression area. An ideal standard force per m sealing profile is approx. 5000-7000 N / m for one

Claims (1)

192099 2 impression area of Φ-25 mm. Since the permissible change in the shape of the seal is in a certain proportion (25%) to the dimensions of the seal, the height of the seal is increased so that the height is approximately equal to the width. The cavity 3 in the center of the seal is chosen so large that there is room for a change in shape caused by a strong compression. The essential new feature of the invention compared to known seals is the so-called two-stage compression, which is obtained by suitably selecting the wall thicknesses of the seal and by first pressing the cavity 2, after which the entire surface is shown is compressed by the polygon 5. 10 Seal for a hatch cover of a vessel, consisting of a seal made of elastic material such as rubber and attached to the edges of the hatch cover, which, when the hatch cover is closed, is pressed against the top of the hatch head to seal the hatch cover, which seal, viewed in cross-section, is provided with two cavities located one above the other, the lower cavity of which is smaller and is located in the downwardly narrowed bottom of the seal and the other cavity is arranged in the horizontal center of the seal, characterized in that the cavities (2, 3) are wide and kidney-shaped, with a convex side facing the narrowed underside of the seal 20, while two additional cavities (4) are further arranged at the same vertical height between the cavities (2, 3.). Hereby 1 sheet drawing