This invention relates to generally to vehicular and stationary liquid tanks and specifically to apparatus and methods for heating the valves of vehicular water tanks to prevent or undue freezing of such valves.
Trucks and other vehicles carrying large water tanks suffer from cold related problems during inclement weather. One particular problem which occurs is that of valve freezing. This same problem also occurs with stationary tanks, for example xe2x80x9cin fieldxe2x80x9d oil storage tanks.
In a typical vehicle having a water tank, the water tank has an inlet/outlet valve to an outlet line and a vacuum line. The vacuum line induces a vacuum inside the tank to induce water to enter via the inlet/outlet valve. The vacuum line also pressurizes the tank to force water to exit via the inlet/outlet valve.
A vacuum tank or scrubber tank or scrubber may be employed upon the vacuum line to prevent water or evaporated moisture from the tank from reaching the pump which supplies the vacuum or increased pressure. Such a tank may simply serve as a condensate trap. However, in cold conditions the scrubber tank may itself freeze, thus reducing the efficiency of the pump or blocking the line entirely.
The water in the tank is substantially protected from freezing by its large thermal mass. In addition, tank heaters may prevent water in the tank from freezing. While tank heaters are sufficient to prevent freezing of the water in the tank, they are not sufficient to prevent freezing in the various valves, scrubber tanks and other appendages to the tank. Such appendages have relatively little mass and contain relatively little water, thus leaving them open to the certainty of swift heat loss in cold weather. The wind chill induced during vehicle motion, when operating on any parts that have become externally wet, can easily induce freezing even when the actual external temperature is above the freezing point of water. Heaters located in or on the water tank itself are not able to help prevent such freezing. It is normally not possible to entirely clean all the water from the inside of a valve, and even a modest residue is sufficient to freeze a valve (or scrubber, pipe, or other appendage) and render the vehicle inoperable until heat is applied to the affected part.
In addition, when a vehicle is parked for a night, it may suffer freezing which must be undone when the vehicle is next placed into service.
In the past, the most common method of unfreezing the valve was application of a blowtorch to the exterior of the valve to warm the metal until whatever water residue was freezing inside of the valve melted and freed the valve. This has some disadvantages, however, for example requiring trucks to carry blow torches. In addition, it is not uncommon to find a small residue of oil or other petrochemicals remaining in such a tank, even when the tank is ordinarily used to carry water. Vapors from such chemicals have in the past ignited, causing an explosion of the tank. Several accidents a year occur in this manner. Trucks hauling water, fire trucks, street sweepers, trucks going to and from oil rigs, tanker trucks for service stations or airports and numerous other types of vehicles are all plagued by this problem. Vacuum trucks, in particular, are widely used in the petroleum industry to remove and transport a wide variety of products, by-products, wastes and other liquids, including but not limited to flammable and inflammable hydrocarbons, caustics, hazardous materials, etc. Such tanks are often used to service isolated stationary tanks, for example by removal of product, or for spill recovery and material transfers. Such trucks are equipped with a further wide variety of equipment, accessories, and systems to prevent or minimize liquid carryover into the vacuum pump during loading or off-loading. These include filters, baffles, deflectors, swash plates, moisture traps or scrubbers, cyclones, screens, baskets, bags and cartridges, internal and secondary shut-offs, multiple routings, scrubber drain valves, isolation valves, bleeder valves, manifold/inlet/outlet valves and external scrubbers. Such trucks are often protected from over-pressure by relief valves or rupture discs such as pop-offs.
The same problems occur with stationary tanks.
A need exists to prevent vehicular water tank valves, scrubber tanks and lines from freezing, and to undue such freezing when it occurs.
General Summary
The present invention teaches the use of vehicle engine coolant circulated through couplings, sleeves or similar fittings which are utilized at the locations where freezing is likely to occur.
In one embodiment, the invention teaches a manifold heater built to mate with pipe flanges holding between them an ordinary valve.
In an alternative embodiment, the invention teaches a scrubber heater meant to serve as a short section of vacuum line/drain line positioned just beneath the scrubber so as to warm the air entering the scrubber and the scrubber itself as well.
In an alternative embodiment, the invention teaches a quick disconnect cuff for unfreezing valves, pipes or accessories other than those on the vehicle or stationary tank equipped with the invention.
Summary in Specific Reference to the Claims
It is therefore one aspect, advantage, embodiment and objective of the present invention to provide a water tank valve heater for use upon a water cooled vehicle engine, the heater comprising: 1) a first coolant line having first and second ends, the first end being operatively connected to such vehicle engine by which means coolant may pass between such vehicle engine and such first coolant line; 2) a second coolant line having third and fourth ends, the fourth end being operatively connected to such vehicle engine by which means coolant may pass between such vehicle engine and such second coolant line; 3) a heater body disposed at such valve, 4) the heater body having a coolant conduit therethrough, the coolant conduit having an inlet and an outlet in operative connection with each other, the second end and third end being operatively connected to such heater body respectively at the inlet and outlet, by which means coolant may pass between the first and second coolant lines.
It is therefore another aspect, advantage, embodiment and objective of the present invention to provide a heater wherein the heater body is disposed at such valve by being secured to a pipe entering such valve adjacent to the valve.
It is therefore another aspect, advantage, embodiment and objective of the present invention to provide a heater wherein the heater body is disposed at such valve by being secured directly to such valve.
It is therefore another aspect, advantage, embodiment and objective of the present invention to provide a heater wherein the coolant conduit is serpentine.
It is therefore another aspect, advantage, embodiment and objective of the present invention to provide a heater wherein the coolant conduit widens within the heater body to from a cavity.
It is therefore another aspect, advantage, embodiment and objective of the present invention to provide a heater wherein the coolant conduit divides shortly after entrance of coolant into the heater body, and reunites shortly before exit of the coolant from the healer body.
It is therefore another aspect, advantage, embodiment and objective of the present invention to provide a heater further comprising: 5) first and second couplings at the second and third ends of the coolant lines, the first and second couplings being dimensioned and configured to operatively connect respectively to the inlet and outlet.
It is therefore another aspect, advantage, embodiment and objective of the present invention to provide a heater further comprising: 6) a bypass valve having first and second positions, the first position allowing flow of coolant directly from the second end to the third end, the second position preventing flow of coolant directly from the second end to the third end.
It is therefore another aspect, advantage, embodiment and objective of the present invention to provide a heater wherein the material of the heater is one member selected from the group consisting of: steel, aluminum, polymer, and combinations thereof.
It is therefore another aspect, advantage, embodiment and objective of the present invention to provide a heater further comprising: 7) disposed on the surface of the conduit a coolant resistant material comprising one member selected from the group consisting of: a sleeve, an insert, a coating, a treated portion of the heater body, and combinations thereof.
It is therefore another aspect, advantage, embodiment and objective of the present invention to provide a heater used on a generally cylindrical valve, wherein: 8) the heater body is generally cylindrical and hollow, having a diameter greater than such cylindrical valve, 9) the heater body being disposed about the cylindrical valve, and 10) each end of the heater body is closed by means of a generally circular plate having a hole through which the generally cylindrical valve passes, wherein the hole is the same shape and dimension as the exterior surface of the generally cylindrical valve.
It is therefore another aspect, advantage, embodiment and objective of the present invention to provide a water tank scrubber heater for use upon a water cooled vehicle engine, the heater comprising: 1) a first coolant line having first and second ends, the first end being operatively connected to such vehicle engine by which means coolant may pass between such vehicle engine and such first coolant line; 2) a second coolant line having third and fourth ends, the fourth end being operatively connected to such vehicle engine by which means coolant may pass between such vehicle engine and such second coolant line; 3) a heater body disposed at such scrubber, 4) the heater body having a coolant conduit therethrough, the coolant conduit having an inlet and an outlet in operative connection with each other, the second end and third end being operatively connected to such heater body respectively at the inlet and outlet, by which means coolant may pass between the first and second coolant lines.
It is therefore another aspect, advantage, embodiment and objective of the present invention to provide a method of thawing frozen water valves on water tank vehicles and water tanks served by vehicles, the method comprising the steps of: 1) heating engine coolant in an engine, 2) passing the coolant through a heater body disposed upon a water valve.