US3375788A - Sewage lift station - Google Patents

Description

April 2, 1968 J. L. SOLAS ET AL SEWAGE LIFT STATION Filed March 21, 1966 2 Sheets5heet 1 III Ill 50 INVENTOR5 HAROLD A. GADDW JOHNLSOLAS W MM A 7' TORNEYS April 2, 1968 J. L. SOLAS E L SEWAGE LIFT STATION 2 Sheets-Shem 2 Filed Ma rch 21 1966 INVENTORS HAROLD A. GADD ""4 JOHN L SOLAS A TTORNE YS United States Patent Ofi ice 3,375,788 SEWAGE LIFT STATION John L. Solas, Kansas City, and Harold A. Gadd, Grandview, Mo., assiguors to Forslund Pump and Machinery Co., Inc., Kansas City, Mo., a corporation of Missouri Filed Mar. 21, 1966, Ser. No. 536,164 5 Claims. (Cl. 10387) ABSTRACT OF THE DISCLOSURE A sewage lift station receiving sewage from a reservoir and discharging the sewage to sewage disposal means is precast of a settable plastic material such as Portland cement concrete or a urethane resin. The station has floor, side wall and ceiling structure integrally formed as a unit and has an aperture formed in the ceiling structure to receive a precast entrance tube which is supported on the ceiling structure and extends upwardly therefrom. The station has a plurality of intake lines connected to a discharge line with pumping means and valve means positioned in each intake line to move sewage from the reservoir to the disposal means.

This invention relates to the field of sewage disposal and more particularly, to a new and improved sewage lift station.

The typical prior art precast concrete sewage lift station is formed of a floor structure and side walls with a lid or ceiling structure separately formed from the side walls and laid in place or assembled and sealed at the site of the station installation. In such a prior art station, the discharge pipe from the lift station extends through the side wall of said station and terminates in a flange pipe fitting for receipt of a pipe elbow and a vertical pipe section which is installed under field conditions at the installation site after placement of the station in an excavated area.

Various problems have arisen in the art in connection with sewage station construction of the type described above, some of which are discussed in the following. Because of the location of the vertical pipe section of the discharge line, it is impossible to obtain the proper backfill compaction adjacent the side wall of the station in the area of the vertical pipe section, as the soil compaction operation is likely to cause the various seals in the line to loosen resulting in eventual leakage. The location of this vertical pipe section also requires an additional amount of excavation to allow for the installation of the pipe section and the formation of various pipe joints. In addition to the above problems, repairs on the discharge line from the lift station can be quite difiicult due to the depth at which the discharge line and the associated fittings are disposed. It should also be noted in regard to repair problems that the seals utilized to join the various fittings and the vertical pipe section in the discharge line are formed under field conditions and as a result, are not as dependable as seals within the precast sewage station which are formed in the factory under ideal conditions. Various problems have also resulted from seepage of ground water into the sewage stations of the prior art around the lid or ceiling structure, thereby causing deterioration of the equipment within the station.

The principal objects of this invention are: to alleviate the aforementioned difficulties in the art by providing a new and improved precast sewage lift station having a monolithically formed shell or housing of a plastic settable material; to provide such a structure wherein the vertical pipe section and its associated fittings and joints 3,375,788 Patented Apr. 2, 1968 of the sewage discharge line are located within the monolithic shell; to provide such a structure for underground use wherein the pumps, motors, controls and the piping including the vertical discharge piping are connected under factory conditions and mounted within the shell, thereby providing a complete lift station assembly ready for installation in an excavated area of the job site with minor connections of piping to tie the station to the wet well and sewage disposal line; to provide such a structure where the vertical piping section of the sewage discharge piping from the station extends from its connection to the pumping apparatus vertically through the interior of the shell and through an aperture defined through the ceiling structure of the shell, said installation of the vertical discharge piping occurring in the factory with the sewage lift station assembly delivered to the installation site ready for placement in an excavated area and connection to the wet well and sewage disposal line; to provide such a structure where the installation in the field may be conducted without the employment of highly trained personnel; to provide such a structure wherein the station may be placed in an excavated opening and back-filled with proper compaction of the back-fill around the sides of the station avoiding washouts of soil and the build-up of excessive liquid pressures on the exterior of said shell; to provide such a structure having a shell or housing wherein the ceiling structure is monolithically formed to or integral with the side walls, thereby eliminating the lid-like ceiling structures of the prior art devices, thereby reducing the possibilities of leakage of ground water into the interior of the lift station; to provide such a structure wherein the vertical pipe section of the discharge line and its associated fittings and joints are easily accessible for repairs and replacements; to provide such a structure which may be completely formed in the factory under controlled conditions, thereby reducing expensive field installation costs and providing a properly sealed piping system; to provide such a structure formed of either a reinforced concrete or reinforced synthetic resin such as a urethane.

Other objects and advantages of this invention will become apparent from the following description taken in connection with the accompanying drawings wherein are set forth by way of illustration and example certain embodiments of this invention.

FIG. 1 is a vertical sectional view taken on line 1-1 of FIG. 3 through a sewage lift station embodying the features of this invention and its associated wet well, said station and well being shown in their installed position on a concrete pad in the ground.

FIG. 2 is a vertical sectional view showing an excavated area having concrete pad poured in said area and a wet well constructed thereon with a sewage lift station formed of a precast shell and including therein a sewage pumping system, said lift station being shown in its position adjacent the excavation area in the form in which the lift station is delivered from the factory and ready for installation by connection to the wet well and the sewage disposal means.

FIG. 3 is a horizontal sectional View through the wet well and the sewage lift station looking downwardly illustrating the dual pumping system Within the sewage station and its associated connections.

Referring to the drawings in more detail:

The reference numeral 1 generally designates a combination of structures for the collection and pumping of sewage and the like including a wet well or collecting reservoir 2 and a sewage lift of pump station 3 operatively connected to the wet well 2 for removing sewage from said wet well 2 for the passage of said sewage into a sewage disposal line. The structure illustrated is exemplary only as it is contemplated with a sewage lift or pump station constructed having a shell including at least a ceiling structure and a side wall wherein said ceiling structure and said side wall are integrally formed in a monolithic manner using a plastic settable material.

In the illustrated structure, the sewage lift station 3 includes a shell or housing 4 and a tubular entry member or entrance tube 6. The housing or shell 4 may be precast under factory conditions and, as illustrated, has a floor structure 8, a cylindrical side wall and a ceiling, roof or lid structure 12 integrally formed to provide a monolithic shell for housing the various control mechanisms and pumping means 13 employed in passing the sewage fro-m the wet well 2 to a sewage disposal line 14. The ceiling structure 12, as illustrated, defines a through aperture 16 about which is mounted the entrance tube 6 to allow access from the ground level 17 to the interior of the shell 3 through the entrance tube 6 which contains a conventional ladder structure 18. The shell 4 has a plurality of lifting rings 19 (not shown) suitably retained in the ceiling structure 12 to which a liftingrneans may be attached for lowering the station 3 into an excavated area. Considerable difficulty is experienced in lowering prior art stations into such an area without cracking or otherwise damaging the structure as such rings may not be used in these structures. As a result, the present day procedures for lowering the structures are costly and time consuming.

In the illustrated structure, the shell 4 is monolithically formed of a plastic settable material as concrete including a plurality of horizontal and vertical reinforcing bars 20 disposed within said concrete in accordance with conventional practice of reinforcement of hollow underground structures. Lightweight concrete may be utilized in the ceiling structure to reduce the load in the ceiling structure or may be utilized throughout the shell by utilizing various types of conventional light aggregate in the concrete mix. It is also contemplated that a monolithic shell, as illustrated by shell 4, may be formed of other suitably reinforced plastic settable materials, such as reinforced resins, as for instance, a urethane or other resins providing the desired resistance to the chemical and physical deterioration of the sewage structure of this type. Resins of this nature may be suit- :ab'ly reinforced as by various glass fibers, metals or the like to withstand the forces imposed on an underground structure of this nature.

Referring to FIG. 3, the combination of structures 1 includes a pumping system 22 connecting the wet well 2 to the discharge line 14 and, as illustrated, includes a pair of intake lines 24, each of said intake lines 24 including an intake piping section 26 operatively mounted to each of a pair of pumps 28 through each of a pair of gate valves 30 to provide a dual pumping system in accordance with various governmental regulations, said dual system is normally alternated in usage to maintain the system in operating condition. The pumping system 22 also includes a discharge line 32 extending between and connecting each of the pair of pumps 28 to the sewage disposal line 14. The pumps 28 each discharge into a piping section 34 of discharge line 32 which includes a check valve 36 and gate valve 38. The section 34 is operatively connected to vertical piping or a vertical piping section 40 by means of an elbow Y-pipe fitting 42. The vertical pipe section 40 extends through a suitable opening or aperture 43 defined by the ceiling structure 12 of the shell 4. By so disposing the vertical pipe section 40 through the interior space 44 of the shell 4 and the ceiling structure 12, the vertical discharge line 32 may be in stalled in the factory during the formation of the precast lift station, thereby permitting the formation of the various joints associated with the vertical discharge line 32 to be made under factory conditions. Suitable fittings are employed on the upper end 46 of the vertical discharge line 32 to connect said line 32 to the sewage disposal line 14. The distance to which the vertical pipe section 40 extends above the ceiling structure 12 of the shell 4 is dependent upon the relative installation depths of the shell 4 in the sewage disposal line 14. Referring to FIG. 2, the precast lift station 3 is shown as it would be delivered to the installation site having a pair of intake lines 26 extending horizontally through the side wall 10 of the shell 4 and the vertical pipe section 40 of the discharge line 32 extending outwardly through the ceiling structure 12 in a vertical manner. All of the interior piping and control mechanisms :have been previously installed in the factory and are ready for rapid installation and connection in the excavated area to the wet well 2 in the sewage disposal line 14.

As the ceiling structure 12 is integrally precast in the factory with the side wall 10 and floor 8, a pair of pump driving motors 47 may be mounted to the cetiling structure 12 at the factory and each operatively connected to a pump 28 by a flexible drive shaft 48 and suit-able couplings 50 thereby eliminating the necessity of field installation of the motors 47. This arrangement facilitates maintenance of the pumps 28 by allowing the motors 47 to be mounted in vertically spaced relation to the pumps 28 as opposed to the conventional practice of mounting the motors directly to the pumps, thereby eliminating the necessity of hoisting the motors 47 off .the pumps 28 to maintain the pumps 28.

The shell 4 of the illustrated embodiment may be formed by various methods of monolithically pouring enclosed structures of this type, as for instance, forming up the floor structure 8 and pouring concrete after suitable placement of the reinforcing rods 20 in the proper arrangement. After the concrete is allowed to partially set, the side walls 10 of the shell 4 are formed up using suitable forms of a collapsible nature such that they can be removed through the aperture 16 of ceiling structure 12 and the side walls 10 was poured. The forms for the side walls may be supported on various means in various manners such that the load of the forms is not imposed on the floor structure 8. The ceiling structure 12 may be formed up simultaneously with the placement of forms for the side walls 10 and poured with the side walls 10 or after the side walls 10 have .had an opportunity to partially set. Such methods of monolithic pouring are conventional in the art and could be conducted in various manners to produce the desired structure.

After completion of the shell structure 4, the pumping system 22 and the associated pumping means and valves may be installed in the shell 4 under factory conditions. The various piping sections may be positioned and aligned through suitable apertures in the side walls and ceiling structure and the proper seals formed between the various components of the pumping system 22 to provide a tight system. The motors 47 are then mounted to the ceiling structure 12 and the drive shafts 48 operat-ively connected between the motors 47 and pumps 28 along with installation of various control mechanisms and other equipment.

It is to be understood that while we have illustrated and described one form of our invention, it is not to be limited to the specific form or arrangement of parts herein described and shown except insofar as such limitations are included in the claims.

What we claim and desire to secure by Letters Patent 1. A sewage lift stat-ion for receiving sewage from a reservoir and discharging said sew-age to sewage disposal means, said lift station comprising:

(a) an integral precast shell of plastic settable material having a floor structure, side wall and ceiling structure, said ceiling structure having an aperture therein;

(b) a precast entrance tube having one end mounted in said ceiling structure aperture and extending upwardly from said ceiling structure, said entrance tube being positioned to provide an entry-way to the interior of said shell;

(0) a plurality of factory installed intake lines each being adapted to be connected to said reservoir; (d) a factory installed discharge line adapted to be connected to said sewage disposal means, said discharge line having a vertical section positioned within said shell and extending upwardly through said ceiling structure, said intake lines being connected to said discharge line within said shell;

(e) factory installed pumping means within said shell and associated with each of said intake lines, said pumping means being adapted to move said sewage from said reservoir .to said discharge line; and

(f) factory installed valve means within said shell and positioned in each of said intake lines between said reservoir and said pumping means and between said pumping means and said discharge line.

2. A sewage lift station as recited in claim 1 wherein the shell of said lift station is formed of a reinforced resin.

3. A sewage lift station as recited in claim 2 wherein the resin is a urethane.

4. A sewage lift station as recited in claim 3 wherein the urethane is reinforced by glass fibers.

5. A sewage lift station as recited in claim 1 wherein the pumping means includes a pair of pumps and a pair of motors and wherein said motors are operatively and adjustably mounted to the ceiling structure of the shell and within said shell in spaced relation above said pumps, each of said motors being operatively connected to one of said pumps by a flexible drive shaft for driving said pump, said pumps, motors and piping being operatively connected in the factory and delivered to the station installation site pre-assembled and ready for rapid installation.

References Cited UNITED STATES PATENTS 1,494,875 5/1924 Yeomans 103-26 1,613,007 1/1927 Yeomans 103-26 3,097,166 7/1963 Monson 52-169 X 3,122,860 3/1964 Schulze 52-309 3,145,502 8/ 1964 Rubenstein 52-309 ROBERT M. WALKER, Primary Examiner;

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