AU2005220277B2 - Base for a Drainage System - Google Patents

Abstract

P30priic'Specificatas fId\12497412 Rmic AustraliAUt mple24 dc.1 IIW5 -10 The drainage base includes a body having various surfaces. A lower surface, an outer side wall and an upper edge form the outside of the base. An internal surface extends 5 downwardly from the upper edge and defines a recess having an exit channel for discharge of fluid material. The internal surface is formed, at least in a lower part, in the shape of an inverted cone. The inverted cone has a rounded tip forming a collection point for flowable material to be discharged through the exit channel. 10 (Figure 6) 3ee Ic-

Description

AUSTRALIA PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT (ORIGINAL) Name of Applicant: Rinker Australia Pty Limited (previously named: Readymix Holdings Pty Ltd) Actual Inventors: Ronald William Green Address for Service: DAVIES COLLISON CAVE, Patent Attorneys, Level 3, 303 Coronation Drive, Milton 4064, Queensland. Invention Title: "Base for a Drainage System" Details of Associated Provisional: Application No. 2004905831 / Filing Date: 11 October 2004 The following statement is a full description of this invention, including the best method of performing it known to us: Q:\Ope'akcUOO 5October 2005\12497412 readymix complete filing AU application 284.doc.doc - 1/10/05 P0pecr0l\Specificatid s as ficdI2497412 RIkcr Australia AU compIew 284 dm- I I10105 BASE FOR A DRAINAGE SYSTEM FIELD OF THE INVENTION 5 THIS INVENTION relates to bases for use in drainage systems for collecting flowable material from one or more inlet pipes and directing it to an outlet pipe. Typically, such bases form the foundation of a structure to provide access to the drainage system. The structure may be a manhole but has a wider range of applications. The base may be particularly suited for a sewerage system but is not so limited. The base is 10 preferably adapted for production by casting in an appropriate material. BACKGROUND OF THE INVENTION It is common to form inspection apertures or manhole access apertures in 15 drainage systems by locating a drainage base at an appropriate depth and then forming a cylindrical access tunnel to the ground surface, thereby providing access for maintenance tasks and inspection and blockage relief activity. Typically, a base will include a cavity for receiving fluid material before directing it to the outlet. The cavity is usually formed with one or more open drain channels adapted to direct fluid from an inlet/s to the outlet. 20 Multiple drain channels may be provided when more than one inlet accesses the base. The bases are usually built to order to allow for the idiosyncratic angle requirements and depth and exit requirements of a particular application. Typically, a blank will be cast out of concrete or similar material. Once the specific requirements of the base are provided, the blank will be benched or finished manually by a plasterer to 25 provide necessary curves and sloping surfaces that will allow easy or effective outflow of material. Each base therefore requires considerable manual input leading to significant costs associated with their structure. There is also a considerable time delay between receiving an order and production of a manually finished base suitable for a job. Additionally, the quality of the finish of the product varies somewhat due to the natural 30 fluctuations in the work produced by manual finishers.

C:NRPorbl\DCC\LJR\2(N366_ DOC-8/I/2011 -2 SUMMARY OF THE INVENTION The present invention seeks to provide an improved base for a drainage system or at least to provide alternative to existing base arrangements. 5 In a first aspect, the invention resides in a drainage base including: a body having a lower surface; a side wall having a side wall outer surfacer continuous with the lower surface; an upper edge continuous with the side wall; and an internal surface extending downwardly from the upper edge and defining a recess, the internal surface formed, at least in part, in the shape of an inverted cone. 10 Preferably, the inverted cone may have a rounded tip. The rounded tip may form a collection point for flowable material discharged into the recess. Alternatively, the tip may be formed in any shape that provides acceptable flow characteristics to form a collection point in a specific application. For example, the tip may be substantially pointed or even box-like in some instances. 15 The base may also include an exit channel in fluid connection with the collection point and adapted to direct the flowable material away from the collection point and out of the base. The exit channel may include an outlet aperture which is conveniently adapted to mate with an outlet drainage pipe. The arrangement may include a sealing arrangement such as a compression seal. 20 The access arrangement may be a manhole. Alternatively or additionally, the access arrangement may be a non-man entry inspection or access point of the drainage system. The drainage system is preferably a sewerage system but may be other alternative drainage systems. The body may be formed of concrete. Alternatively, the body may be 25 formed of a plastics material. In an alternative embodiment, a laminar construction may be formed with a plastic inner liner and outer concrete shell. This may provide some advantage in manufacture and also provide better resistance to long term damage by acid produced by hydrogen di-sulphide gas in sewage. The plastic liner may be formed inverted and have concrete poured over its upper surface (ie. the liner may act as an 30 included mould). The base may include a flange located at or around the junction of the lower surface and the side wall surface. The flange and lower surface may form a foot for positioning and support of the base underground. The flange may include two or more C \NRPorbl\DCCJR\3204366 DOC-81ll 2011 -3 anchor points to facilitate lifting of the base. The flange may include three anchor points evenly spaced around its circumference. The lifting points may include foot anchors as are well known to a skilled addressee. The side wall outer surface may be substantially perpendicular to the plane 5 of the lower surface, or may be sloped to provide an alternative to the flange for fixing the base in the soil. The upper edge may form a spigot or socket arrangement for receiving an extension shaft for extending the base towards the surface of the ground and providing access to the recess. The spigot or socket may be formed as a lipped structure. 10 The internal wall may be formed in one section with an evenly sloped surface. The internal wall may be formed with an upper section and a lower section, the lower section formed in the shape of an outer wall of a cone with a tip as described above. The upper section may also be formed in the shape of a section of an outer wall of 15 an inverted cone but having a more upright angle. The upper section and lower section may join at a defined angular junction. The exit channel may be formed or cut into the wall of the lower section leading to the outlet aperture. The formed outlet or cutting may have substantially vertical sides. A fall is conveniently provided away from the collection point and towards the 20 outlet aperture when in operation. The aperture may be adapted to receive an outlet drainage pipe and a sealing arrangement such as a compression seal. An exit hole may extend through the side wall between the exit channel and the outlet aperture. The base may also include one or more inlet passageways, the one or more inlet passageways extending through the side wall of the base may be formed or cut and 25 adapted to discharge onto the inner wall surface above the collection point. Each inlet passageway may have an inlet aperture adapted to receive an inlet drainage pipe. The aperture may be adapted to receive the pipe and a sealing arrangement such as a compression seal. Each of inlet passageways may include an inlet hole extending through the side wall to an inlet aperture in the side wall outer surface. 30 The base may be formed by casting.

P\0pcrialciapeedicaens afilen2497412 Rmkr Aumlia AU caplae 284 doc-I I/10V -4 LIST OF FIGURES Preferred embodiments of the invention will be described by way of example, with reference to the accompanying drawings in which: 5 FIG. I is a plan view of a drainage base; FIG. 2 is a sectional view of the base in FIG. 1, along direction A; FIG. 3 is a sectional view of the base in FIG. 1, along direction B; FIG. 4 shows a variation on the base with a view comparable to FIG. 2; FIG. 5 shows the variation with a view comparable to FIG. 3; and 10 FIG. 6 is an isometric view of the base in FIG. 1. DESCRIPTION OF PREFERRED EMBODIMENTS Referring to FIG. 1, there is seen a base 10 having an annular flange 12 15 around an outer surface 14. The outer surface 14 is continuous with an upper edge 16 which is continuous with an inner surface 18. A recess 21 is provided in the inner surface. An exit channel 20 is directed form the recess towards an outlet aperture 22 shown in hidden detail. The outlet aperture 22 is adapted to receive an outlet drainage pipe (not shown). 20 One purpose of the flange is to stabilise the base by providing resistance to upward movement should the base "float" in the soil under some conditions. An alternative is for the outer surface 14 to slope outwards from the upper edge 16 to provide similar resistance to displacements when located underground. If present, the annular flange has a recess 15 to facilitate formation of the outlet channel. Lift anchors 24 are also spaced about the 25 flange 12 and provide lifting points for attachment of slings and a hoist when moving the base. When formed of concrete and with significant dimensions, the base has a substantial weight which requires mechanical lifting devices, such as forklifts, to be utilised for its transfer. The inner surface has an upper section 26 and lower section 28. In an 30 alternative embodiment, the lower section may extend to the upper edge. An inlet passageway 30 is shown in hidden detail and comprises an inlet aperture 32 formed as a pipe receiving recess and inlet passageway 34. The lower section 28 terminates in a P Oper\ukSecifictaa M as filed124974i2 Rmkr Aumtrli. AU compltt. 2S4 doc-I I/MI S -5 collection point 36 which is positioned to receive material flowing down the inner surface 18. Referring to FIG. 2, there is seen the base 10 of FIG. 1 in a sectional view taken in the direction of arrows A. The base 10 has a lower surface 38 which meets the 5 outer surface 14 to form the annular flange 12. The annular flange 12 is optional. The exit channel 20 is seen running into outlet aperture 40. The collection point 36 is also seen formed as a curved tip of the lower section 28 of the inner surface 18. The lower section 28 defines the recess in company with the upper section 26. The lower section 28 may extend into and include the top section with a consistent angle to the surface. The 10 slope of the inner surface may be at any angle suitable to provide adequate drainage for intended flowable material, preferably while eliminating deposits of solid materials on the surface. The flow characteristics of a slurry may demand a steeper angle if the slurry is less fluid and more viscous. Alternatively, a more liquid slurry may drain effectively on a flatter angle. The lower section is formed in the shape of the outer wall of an inverted 15 cone. The wall of the upper section 26 is also formed in the shape of the outer walls of a truncated cone at a steeper angle to the lower surface 28. The lower section 28 and upper section 26 meet at an angled join line 42. The upper edge 16 is formed as a lipped spigot or socket 44 adapted to receive an extension piece, such as a cylindrical pipe section, to provide access to a ground surface. 20 The dimensions and proportions indicated in the figures are representative only, and the base may be formed to suit larger or smaller circumstances as necessary. It may be formed to provide access for a person to carry out maintenance tasks or unblocking operations. Alternatively, it may be provided in smaller dimensions so that access may be provided for mechanical tools, CCTV cameras and similar to carry out necessary 25 operations or similarly as an inspection opening. A prototype base had a width of 1480mm with a 75mm rise on an edge of the flange and a 75mm sloping ledge from the flange to the outer surface 14 of the wall. The wall may be approximately 675mm high and the outer diameter of the wall being 1280mm. The upper section of the inner surface may extend vertically for around 250mm 30 and the lower section extends 275mm. These dimensions are exemplary only. The base in FIG. 3 shows the arrangement of FIG. 1 in section in the direction of arrows B. The outlet aperture 40 is formed with a recess 46 leading to a P.\Oper\aclSpecificAtin a fild12497412 Rinkla A lAU ai npcte 284.d-nI/10/05 -6 shoulder 48 adapted to receive an outlet pipe and seal mounted to the pipe to form a sealing arrangement. A lip of pipe may be positioned in the pipe receiving recess 50. The seal is preferably formed as a compressible seal having two metallic flanges with connecting through bolts. Tightening of the bolt and nut combination will lead to 5 distortion of an elastomeric seal between the two plates and compression into the lateral wall of the aperture 48 to thereby seal the fitting. The seal also compresses against a circumference of the pipe. The exit hole 20 is manufactured with a fall through the concrete base 52. An inlet hole 34 is provided through the wall and base 52 to enter above the collection point 36, thereby providing fall for any slurry, liquid or other flowable 10 material that enters through the drain. The fall will take the material through the outlet aperture 40 and away through an outlet drainage pipe. One of the possible advantages of this base is that it may be formed by casting providing a smooth finish surface which allows inlet apertures to be cored or cast at any preferred angle and position provided they do not interfere with the exit channel and 15 enter above the collection point. Material may be brought in at appropriate angle and will flow around the conical surface to exit smoothly from the base. The method of construction may include casting the outlet aperture. It may include casting one or more inlet apertures or holes if appropriate. The base may be formed with a composite structure of plastic and concrete. An inner liner may be formed which defines the shape of the inner 20 surface. It may also define the outlet channel and/or one or more inlet passageways. The inner liner may be formed by moulding and rotational moulding may be particularly suitable. The inner lining may be inverted inside an outer casing defining the outer dimensions of the base. Concrete may then be poured into the outer casing to set around 25 the liner. The plastic liner may enhance the longevity of the base due to resistance to the effect of acid and caustic fluids. It is envisaged, however, that the present bases will be mass-produced with an outlet channel formed. Orders may then be received for specific base requirements allowing the manufacturer to core an appropriate inlet hole or holes for a particular base and application. Having the bases ready for use may provide an efficient 30 and cheaper form of base production with less delay at the job site. This should increase the efficiency of the operation. FIGS 4 and 5 show base 100 which is a variation on the base 10 of FIGs. 1, CWRPonb\DCC\URk1204366_ DOC-4/11/2011 -7 s2, 3. In this example the upper part 111 of the inner surface meets the lower part 112 in a horizontal surface 113 which provides a step for inspectors to assist maintenance of the drainage system. The step may be provided in many forms, and may or may not extend fully around the inside of the base. In the absence of the step the join 142 between the 5 upper and lower parts of the inner surface continues as before. In this case the step extends at least half way around the base and includes a short vertical portion 114 in order that the join 142 is at the same level as the surface 113. An exit channel 120, recess 121 and collection zone 136 are provided as before. FIG. 6 shows an isometric view of the base 10 when complete and having 10 the recess 21 and exit channel 20 formed in the base thereby ready for finishing and movement to an appropriate job site. The reference in this specification to any prior publication (or information derived from it), or to any matter which is known, is not, and should not be taken as an acknowledgment or admission or any form of suggestion that the prior publication (or 15 information derived from it) or known matter forms part of the common general knowledge in the field of endeavour to which this specification relates. Persons skilled in the art will appreciate that numerous variations and modifications will become apparent. All such variations and modifications which become apparent to persons skilled in the art, should be considered to fall within the spirit and 20 scope that the invention broadly appearing before described.

Claims (12)

1. A drainage base including: a body having a lower surface; 5 a side wall having a side wall outer surface continuous with the lower surface; an upper edge continuous with the side wall; an internal surface extending downwardly from the upper edge and defining a recess having an exit channel for discharge of fluid material from the base, wherein the internal surface is formed, at least in a lower part, in the shape of an inverted cone, and 10 wherein the inverted cone has a rounded tip forming a collection point for flowable material to be discharged through the exit channel; and, one or more inlet passageways extending through the side wall and adapted to discharge onto the internal surface at a level above the collection point. 15

2. A base according to claim 1 wherein the internal surface has an upper part in the shape of an inverted cone having a steeper angle than the lower part.

3. A base according to claim I wherein the internal surface has an upper part which meets the lower part in an angular junction which extends at least part way around the 20 inside of the base.

4. A base according to claim I wherein the internal surface has an upper part which joins the lower part through a horizontal step which extends at least part way around the inside of the base. 25

5. A base according to any one of claims 1 to 4 wherein the exit channel is formed or cut into the wall of the lower part and leads through the base to an outlet aperture in the side wall outer surface. 30

6. A base according to claim 5 further including an exit hole extending through the side wall between the exit channel and the outlet aperture. C :RP1onb\DCC\JR\320366_ I.DOC-4/ll/201 -9

7. A base according to any one of claims 1 to 6, wherein each of the one or more inlet passageways include an inlet hole extending through the side wall to an inlet aperture in the side wall outer surface. 5

8. A base according to any one of claims 1 to 7 further including a flange located at or around the junction of the lower surface and the side wall outer surface.

9. A base according to any one of claims 1 to 8 wherein the side wall outer surface slopes outwards from the upper edge to the lower surface. 10

10. A base according to any one of claims I to 9 wherein the upper edge forms a spigot or socket arrangement for receiving an extension shaft for extending the base upwards and providing access to the recess. 15

11. A base according to any one of claims 1 to 10 wherein the base is formed by casting.

12. A drainage base substantially as herein described with reference to the accompanying drawings.