GB2630633A

GB2630633A - Inspection chamber sediment trap and method of trapping sediment which enters a drainage system

Info

Publication number: GB2630633A
Application number: GB2308198.7A
Authority: GB
Inventors: Robin Beale James
Original assignee: Sieve Lids Ltd
Current assignee: Sieve Lids Ltd
Priority date: 2023-06-01
Filing date: 2023-06-01
Publication date: 2024-12-04
Also published as: GB202308198D0

Abstract

A sediment trap 10 in the form of a tray or pan for locating in a drainage inspection chamber below a manhole cover 21, having a base 12 defining a sediment trapping area, a wall 11 extending around the periphery of the base and a flange 13 extending outwardly from the wall for engaging the shoulder 23 at the edge of an inspection chamber. In use fluid, e.g. rain water with entrained material e.g. sand, silt, cementitious material from a building site flowing from a ground surface, between the manhole cover and the edges of the chamber, predominantly flows into the trap 10, wherein sediment can settle to the base, walls 11 act as weirs allowing relatively clean fluid to flow into the manhole. Corners of the tray may include apertures (35, Fig. 2) through which cleaned fluid flows into the chamber, and allowing passage of fixing means 26 for the cover. The tray may include an L-shape bracket (17) with a keyway for aligning with a keyway in the cover, facilitating removal of both cover and tray with a tool. Also claimed is a method of trapping sediment.

Description

INSPECTION CHAMBER SEDIMENT TRAP AND METHOD OF TRAPPING SEDIMENT WHICH ENTERS A

DRAINAGE SYSTEM

The present invention relates to an inspection chamber sediment trap for a drainage system and to a method of trapping sediment which enters a drainage system.

Sediment, including sludge, cementitious material, dirt and the like which enters drainage systems can quickly build up and obstruct the drainage ducts creating a blockage. This can create health risks owing to the build up of sewage and the like. The problem is exacerbated on building sites where the drainage systems are installed prior to the construction of any dwellings. Building materials, including sand, gravel and cementitious products which are used to build the dwellings can easily pass into the drainage systems during heavy rain for example, and over a period of time can lead to an obstruction in the drainage system. This sediment is typically washed into the drainage system, by passing between a manhole cover and the respective inspection chamber.

There are various examples of sediment collection and trapping systems in manhole/inspection chambers. One example is a flexible disk that is inserted into the manhole prior to the performance of the debris-creating work, and is unfolded by an unfolding mechanism until a periphery of the disk rests against a bounding wall of the chamber.

It is also known to use circular adapter rings with a waste basket, a filter fabric, an interior mesh and an inner casing configured to capture sediment. Such devices are suitable for installation within existing manhole frames without significantly impacting the height of the manhole cover and may be used within manholes for underground dry wells, storm drains, catch basins and other similar types of water collection structures.

The existing solutions, however, have certain limitations. In particular, traditional sediment trapping devices consist of multiple components, which limits their reliability over long term usage. Furthermore, deployment and dismantling of traditional sediment trapping devices require additional strenuous effort which is not desirable especially in high-risk and hazardous areas such as drainage systems. It is an object of the present invention to provide a provide an inspection chamber sediment trap and method of trapping sediment which addresses at least some of the above-mentioned problems.

Summary of the invention

In accordance with the first aspect of the present invention, there is provided an inspection chamber sediment trap for a drainage system, the sediment trap comprising: - a tray comprising a base defining a sediment trapping area and a wall which extends around a periphery of the base; - at least one flange which extends from the wall for engaging with an inspection chamber of a drainage system.

The inspection chamber sediment trap is configured to collect and trap contaminants suspended in surface water which pass into drainage systems. The surface water around such areas may be contaminated due to various factors such as roadworks, traffic, human interaction and the like.

Drainage systems including underground pipe structures, receiving drains, manholes, pumping stations, storm overflows and screening chambers typically have a ground level entry point through a manhole directly into the ducting arrangement or into an inspection chamber. The manhole is typically protected by a manhole cover, traditionally made of metal, but may be constructed from composite materials. Manholes are usually outfitted with a manhole frame upon which a manhole cover is placed to cover the manhole.

In an embodiment, the inspection chamber sediment trap further comprises at least one keyway for receiving a tool for lifting the sediment trap from the inspection chamber of the drainage system. The at least one keyway is arranged to align with a keyway associated with a cover of the inspection chamber of the drainage system.

In an embodiment, the at least one keyway is disposed in a bracket which extends from the wall over the base of the tray.

In an embodiment, the tray defining the sediment trapping area comprises a substantially rectangular cross-sectional shape. However, it is to be appreciated that the shape is arranged to substantially conform with the cross-sectional shape of the chamber within which the trap is arranged to locate. In a further embodiment, the base comprises a truncated rectangle, in which the corner sections are removed.

In an embodiment, the wall is coupled at a proximal end thereof to the base and a distal end of the wall forms an open periphery of the tray. The flange extends around the open periphery, outwardly of the tray. In an embodiment, the flange comprises a continuous flange.

In an embodiment, the flange comprises a notch formed therein adjacent corner regions of the tray. The trap can comprise two notches, one being disposed in opposing corner regions of the tray.

In an embodiment, the trap is symmetric about an axis which extends diagonally across the tray between the corner regions. In an alternative embodiment, the trap comprises mirror symmetry about a plane which extends substantially perpendicular to the base, across the tray between the midpoint of opposing sections of the wall.

In accordance with the present invention as seen from a second aspect, there is provided a method of trapping sediment which enters a drainage system, the method comprising the use of an inspection chamber sediment trap according to the first aspect.

Whilst the invention has been described above, it extends to any inventive combination of features set out above or in the following description. Although illustrative embodiments of the invention are described in detail herein with reference to the accompanying drawings, it is to be understood that the invention is not limited to these precise embodiments.

Furthermore, it is contemplated that a particular feature described either individually or as part of an embodiment can be combined with other individually described features, or parts of other embodiments, even if the other features and embodiments make no mention of the particular feature.

Thus, the invention extends to such specific combinations not already described.

The invention may be performed in various ways, and, by way of example only, embodiments thereof will now be described with reference to the accompanying drawings, in which: Figure 1 is a perspective view of the inspection chamber sediment trap according to a first embodiment of the present invention; Figure 2 is a perspective view of the inspection chamber sediment trap according to a second embodiment of the present invention; and Figure 3 is a perspective view of the inspection chamber sediment trap illustrated in figure 1 arranged in situ within an inspection chamber; and Figure 4 is a sectional view through an inspection chamber with a manhole cover and inspection chamber sediment trap located therein.

Referring to figures 1, 3 and 4 of the drawings, there is illustrated an inspection chamber sediment trap 10 according to a first embodiment of the present invention. The trap 10 is configured to locate within an inspection chamber or manhole 20, below the respective manhole cover 21. Sediment entrained within rainwater for example, which flows between a housing 22 for the manhole cover 21 and the cover itself is arranged to pass into the sediment trap 10. The sediment trap 10 may be formed of a plastics material or a composite material and comprises a substantially rectangular or square cross-sectional shape having an upstanding wall 11 which extends around a periphery of a base 12 of the trap 10. The base 12 and wall 11 collectively define a tray 10a, with the walls acting a weir, so that upon entering the tray 10a, the sediment can settle to the base 12, while the water can pass over the walls 11 into the drainage system.

In an embodiment, the base 12 may comprise a truncated square or rectangular shape in which corner regions of the base 12 are removed. The truncated shape is arranged to conform with an interior shape of the inspection chamber or manhole 20. The trap 10 further comprises a flange 13 which extends outwardly of the tray 10a from an upper region of the wall 12. The flange 13 may comprise a continuous flange and is arranged to abut a shoulder or shelf 23 formed around an interior of the inspection chamber/manhole 20, so that the trap 10 can reside just below the manhole cover 21.

In the embodiment illustrated in figure 1, the flange 13 comprises a notch 14 formed in diagonally opposing corner regions for accommodating a protuberance 24 which extends along the inspection chamber/manhole 20, and which acts to suitably align the trap within the inspection chamber/manhole 20.

Referring to figure 2 of the drawings, there is illustrated an inspection chamber sediment trap 30 according to a second embodiment of the present invention. The trap 30 of the second embodiment is substantially the same as the trap 10 of the first embodiment and so like features have been referenced with the same numerals but increased by 20. The trap 30 of the second embodiment differs from the trap 10 of the first embodiment however in that the flange 33 of the trap 30 of the second embodiment comprises an aperture 35 formed in corner regions. These openings 35 act to further enable water to pass over the walls 31 into the drainage system.

Referring to figures 1 and 2 of the drawings, the sediment trap 10, 30 of the first and second embodiment, further comprises a first and second keyway 16, 36 formed within a respective bracket 17, 37. Each bracket 17, 37 comprises an inverted L-shape with an upper portion 17a, 37a extending from an upper region of the wall 12, 32 inwardly of the tray 10a, 30a, over the base 12, 32 and substantially parallel to the base, with a leg 17b, 37b of the bracket 17, 37 extending from the upper portionl7a, 37a to the base 12, 32. The keyway 16, 36 of each bracket 17, 37 is formed in the upper portion 17a, 37a, and each bracket 17, 37 is located upon the trap to align with corresponding keyways (not shown) formed in the manhole cover 21. In this manner, when an operative (not shown) locates a tool (not shown) within the manhole cover 21 to remove the cover 21, the tool can also extend within the keyways 16, 36 of the trap 10, 30 and lift the trap 10, 30 together with the manhole cover 21.

During use, the sediment trap 10, 30 is located within the inspection chamber housing 22, upon the shoulder 23 of the manhole cover housing 22 and the manhole cover 21 is located within the manhole cover housing 22 over the trap 10. The notches/openings 14, 35 formed at the corner regions of the trap 10, 30 further enable fixings 26, such as screws, which are used to secure the manhole cover 21 to the housing 22, to pass through the manhole cover 21 into respective recesses located in the corners of the manhole cover housing 22. Once the fixings 26 have been secured in place, the sediment trap 10, 30 similarly becomes secured.

Any surface water which passes into the housing 22 between the cover 21 and the housing 22 itself will predominantly pass into the sediment trap 10, 30 and any sediment entrained therein will settle to the base 12, 32 of the tray 10a, 30a. As the tray 10a, 30a fills, cleaned water will then pass over the peripherally extending wall 11, which act as a weir, into the drainage system.

When it is desired to remove the trap 10, 30, the manhole cover fixings 26 are removed, and a manhole cover lifting tool (not shown) is inserted into the keyways 16, 36 aligned in the cover 21 and sediment trap 10, 30. The tool is then manipulated to simultaneously lift the cover 21 and the trap 10, 30 from the housing 22, whereupon the trap 10, 30 can be emptied and cleaned if required.

From the foregoing therefore, it is evident that the inspection chamber sediment trap 10 provides a simple yet effective means for minimising blockages to drainage systems.

Claims

Claims 1. An inspection chamber sediment trap for a drainage system, the sediment trap comprising: - a tray comprising a base defining a sediment trapping area and a wall which extends around a periphery of the base; -at least one flange which extends from the wall for engaging with an inspection chamber of a drainage system.
2. An inspection chamber sediment trap according to claim 1, further comprising at least one keyway for receiving a tool for lifting the sediment trap from the inspection chamber of the drainage system.
3. An inspection chamber sediment trap according to claim 2, wherein the at least one keyway is arranged to align with a keyway associated with a cover of the inspection chamber of the drainage system.
4. An inspection chamber sediment trap according to claim 2 or 3, wherein the at least one keyway is disposed in a bracket which extends from the wall over the base of the tray.
5. An inspection chamber sediment trap according to any preceding claim, wherein the base comprises a substantially rectangular cross-sectional shape.
6. An inspection chamber sediment trap according to any preceding claim, wherein the base comprises a truncated rectangle, in which the corner sections are removed.
7. An inspection chamber sediment trap according to any preceding claim, wherein the wall is coupled at a proximal end thereof to the base and a distal end of the wall forms an open periphery of the tray.
8. An inspection chamber sediment trap according to claim 7, wherein the flange extends around the open periphery, outwardly of the tray.
9. An inspection chamber sediment trap according to any preceding claim, wherein the flange comprises a continuous flange.
10. An inspection chamber sediment trap according to any preceding claim, wherein the flange comprises a notch formed therein adjacent corner regions of the tray.
11. An inspection chamber sediment trap according to claim 10, wherein the trap comprises two notches, one being disposed in opposing corner regions of the tray.
12. An inspection chamber sediment trap according to any preceding claim, wherein the trap is symmetric about an axis which extends diagonally across the tray between corner regions thereof.
13. An inspection chamber sediment trap according to any of claims 1-11, wherein the trap comprises mirror symmetry about a plane which extends substantially perpendicular to the base, across the tray between the midpoint of opposing sections of the wall.
14. A method of trapping sediment which enters a drainage system, the method comprising the use of an inspection chamber sediment trap according to any preceding claim.