COMPOSITE CONSTRUCTED FLOATING SUBMERSIBLE WATER SUPPLY PUMP

Abstract

The disclosure describes the improvement of mobile floating submersible pump systems where such systems are used for rapid deployment water transfer. Such systems are deployed within industrial fire fighting, flood control operations (FIG. 7) and similar water transfer requirements. A floating submersible pump is designed to separate the power system (FIG. 7, item 11), such as a diesel engine, from the pump body (FIG. 7, item 16), which further enables the operator to deploy a pumping system where traditional ground based centrifugal pumps are unable to physically siphon the water. Floating submersible pump systems are cumbersome in nature, requiring heavy equipment and significant manpower to deploy them. The innovation disclosed uses advancements in structural fiber reinforced materials to drastically reduce the weight of such systems, which removes the need for heavy deployment equipment, with the added benefit of corrosion protection from saline environments through the use of chemically inert composites.

Description

BACKGROUND OF THE INVENTION

Municipal and emergency water requirements are frequently mismatched with improper sourcing equipment for rapid deployment and delivery of high-volume water. For example, a typical firetruck is incapable of drafting (i.e. siphoning) water from an open water source (such as a lake or pond) much more than 10 feet below its pump's center-line. This is a common problem of all pumps (most notably centrifugal) as water begins to vaporize within the pump intake under extended suction ranges, causing severe cavitation damage. This is governed by the Net Positive Suction Head Principle; the difference between the pump suction head pressure and the pumping medium vapor pressure at a given operating temperature. Fixed pumping systems, such as that found within a building or refinery, use flooded intakes (often further pressurized by municipal water mains) that alleviate this problem. Additionally, a fire truck may have access to a pressurized hydrant system provided by the municipal water authority to supplement its emergency water needs. Unfortunately, adequate pressurized water infrastructure is unavailable in many remote areas and limited access facilities found among ports, airports and loading facilities.

To overcome these challenges, a submersible pump (submerged just below the waterline), frequently powered by hydraulic fluid systems, is used to supply high-volume pressurized water uphill into the intake of another “on-shore” centrifugal pump. These remote pumps allow a ferrying range limited only by the length of their hydraulic lines, pumping performance capability and system efficiency. Lay-flat hose lines or rolled high pressure tubing are used as replacements for standard metal piping, further increasing the flexibility of such systems. Although these systems exist, they require significant manpower and heavy equipment for deployment due to their weight and cumbersome nature and encounter problems with corrosion in saline environments.

SUMMARY OF THE INVENTION

The Composite Constructed Floating Submersible Water Supply Pump is a solution to traditional bulky mobile rapid deployment high-volume water systems. Reduced weight pump bodies are made of either cast aluminum or welded aluminum plate, making only a marginal weight improvement over traditional cast iron body pumps while also sacrificing material strength and durability. Additionally, aluminum body pumps suffer from galvanic corrosion (without the use of sacrificial anodes) and pitting from highly silted shallow water. Moreover, coating technologies, like hard-coat anodization and polyester powdercoating, are stripped from the aluminum surface during pumping operations because of the abrasive qualities of such heavily silted waters. Constructing a casing from multiple fiber (glass, carbon, aramid or any combination of high strength-to-weight ratio spooled filament material) reinforced thermoset or thermoplastic layers, an extremely strong, durable and lightweight pump casing is achieved. Additionally, the pump impeller is constructed from an isotropic fiber reinforced composite, providing additional weight savings and strength characteristics equal or better than traditional impeller materials such as bronze. Furthermore, the composite body and impeller are completely inert in saline environments, such as seawater or brine storage ponds, eliminating corrosion failure.

BRIEF DESCRIPTION OF DRAWINGS

A more complete understanding of the present embodiment and its respective advantages can be found by referring to the following descriptions and their accompanying drawings:

FIG. 1 illustrates an isometric view of the complete pump assembly.

FIG. 2 illustrates a front view of the complete pump assembly.

FIG. 3 illustrates a side view of the complete pump assembly.

FIG. 4 illustrates an exploded view of the complete pump assembly where item 1 is the pump assembly lifting bar (facilitates overhead movement and deployment), item 2 is the integrated pontoon (to provide flotation to the complete pump assembly), item 3 is the pump motor (hydraulic or electric), item 4 is the motor mounting plate, item 5 is the composite impeller, item 6 is the composite body pump casing, item 7 is the pump discharge connection, item 8 is the pump suction screen and item 9 is the pump assembly external chassis (to facilitate deployment).

FIG. 5 illustrates an isometric view of the composite impeller.

FIG. 6 illustrates an isometric view of the composite body pump casing.

FIG. 7 illustrates an example deployment situation of a floating submersible pump system.

DETAILED DESCRIPTION OF THE INVENTION

The composite constructed floating submersible water supply pump is specifically designed to be ultra-lightweight (comparable to other traditional metal technologies) and highly corrosion resistant to saline environments. By providing such a lightweight system, rapid system deployment for high-volume water transfer needs (such as in municipal de-flooding, FIG. 7) is made possible without the use of heavy equipment, instead substituted by manual manpower.

The composite floating submersible pump is manufactured using well understood commercial manufacturing concepts and intuitive tooling systems. The integral pontoon (FIG. 4, item 2) is made through rotational molding using economical thermoplastic polymers. The same pontoon can also be constructed from typical fiberglass hand layup methods. The motor (FIG. 4, item 3) is a standard commercially available hydraulic or electric motor capable of running submerged in water. The motor external body is sealed, and the surface is treated with a chemically resistant coating to prevent corrosion. The motor mount plate (FIG. 4, item 4) is made from a solid polymer or fiber-reinforced composite plate, which can be cut from any number of commercially available processes such as water jet cutting or 3-axis milling. The composite impeller is machined directly from a commercially available isotropic structural graphite composite monolithic block, with significant weight reduction and equal or better strength than traditional impeller metals such as bronze. The composite body pump casing (FIG. 4, item 6) is made through resin (thermoset or thermoplastic polymer) transfer molding using long strand high-strength to weight ratio reinforcing fibers such as aramid, glass or carbon fiber. Both the impeller and body are chemically inert within saline environments, ensuring zero corrosion.

The pump suction inlet screen (FIG. 4, item 8) is made from a commercially available expanded or perforated corrosion-resistant metal such as stainless steel. The pump assembly external chassis (FIG. 4, item 9) and lifting bar (FIG. 4, item 1) are manufactured from standard mandrel metal bending and welding processes.

It is not readily apparent such a lightweight pump assembly could be developed. Current technology uses a combination of floating barge pumping modules (due to the weight of cast iron pump bodies), crane attached submerged commercial centrifugal pumps or cast (optionally welded) aluminum body pumps fitted with a flotation device. The aluminum body pumps allow for deployment with heavy machinery (i.e. fork lifts, jib cranes, etc.) or manually with adequate manpower. Unfortunately, even the aluminum body pumps are cumbersome to deploy, wasting valuable time resources during rapid deployment requirements. Additionally, aluminum, even with coating technologies, will eventually suffer from galvanic corrosion (if a sacrificial anode is not included in the design) and pitting that nucleates from abrasive silts in shallow water. Moreover, current complex structural wall composites use externally fiber reinforced core materials such as aluminum honeycomb. This method is satisfactory for externally loaded structures but is not strength suitable for highly pressurized containers with internally moving components (such as a centrifugal pump). Large scale mass resin infused short strand fiber reinforced bodies are also not suitable as they sacrifice weight savings with thick resin walls to obtain sufficient strength. In contrast, the composite constructed floating submersible water supply pump casing uses specialized mold architecture combined with long strand woven fiber reinforcements and resin injection molding to drastically reduce the weight of such a system.

The composite submersible pump is used specifically to transfer water (fresh or saline) or similar liquids in remote sourcing situations. A typical remote sourcing situation would be a flooded subway as depicted in FIG. 7. Stormwater has flooded the main subway tunnel (FIG. 7, item 17) where the water level (FIG. 7, item 13) is far below ground level (FIG. 7, item 15) preventing normal centrifugal pump siphoning. A floating submersible pump (FIG. 7, item 16) is powered by an on-shore power module (FIG. 7, item 11) that is remotely connected to the floating submersible pump using a pressurized hydraulic fluid power line (FIG. 7, item 14) or electric line. A water supply hose (FIG. 7, item 12) is connected to the discharge connection of the submersible pump and then to any nearby downstream devices or an open discharge plateau (FIG. 7, item 10). The on-shore power module may be powered by a commercial engine mated to a hydraulic power unit or an electric generator.

The embodiment of this invention is drastically reduce the weight of such systems and provide significant corrosion resistance to enable rapid deployment of remote water transfer systems. By re-tooling woven reinforcement composite technology to manufacture a true structural composite pump casing and impeller, a lightweight and saline environment corrosion-proof system is achieved. This further enables personnel to deploy such systems without the need of heavy equipment, simplifying on-site setup and reducing deployment time.

Claims

1. A portable centrifugal pump comprising:

an integrated flotation device; and

a pump casing manufactured using a composite material comprised of high-strength to weight ratio fiber reinforcements and a thermoset or thermoplastic resin matrix; and

a pump impeller manufactured using a composite material comprised of high-strength to weight ratio fiber reinforcements and a thermoset or thermoplastic resin matrix;

wherein said pump impeller is installed within said pump casing and said flotation device is attached to said pump casing.

2. A portable centrifugal pump according to claim 1 wherein such pump includes integrated frame carrying handles.

3. A portable centrifugal pump according to claims 1 and 2 wherein such pump can be reasonably carried by a single person.