In the aeronautical, aerospace and other industries, the components used are frequently expensive. Due to the high cost of many components, component refurbishment processes are important to return expensive components to service. Refurbishment often includes the removal of field contaminants and coatings or bonding compounds so that new coatings or bonding compounds can be applied to the component.
Refurbishment is generally done by immersing the component in tanks with sufficient amounts of chemicals to clean and/or strip the undesired contaminants, coatings, and bonding compounds. Typically, multiple tanks are needed for the multiple chemicals used in the refurbishment process. Each chemical generally requires its own individual tank. The larger the component, the larger the tank needed and the larger the amounts of chemicals needed to effectively refurbish the component.
This type of refurbishment process offers several disadvantages. First, a high volume of chemicals is needed to provide an immersion tank in which the entire component can be immersed. Chemicals used in the refurbishment process are often expensive. The greater the amount of chemical needed, the greater the expense will be for the refurbishment process. Second, many of the chemicals used in the refurbishment process are hazardous to the environment. The proper waste disposal of chemicals used in the refurbishment process involves additional expenses. When large amounts of chemicals are used in the immersion tanks as described above, large expenses are incurred to properly dispose of the large amounts of chemicals. Also, because many of the chemicals are hazardous, workers involved in the refurbishment process are also required to take the appropriate health and safety precautions. These precautions may provide additional expense. Third, when multiple immersion tanks are used in the refurbishment process, a large area often needs to be reserved for the tanks. When large tanks and a great number of tanks are needed, the refurbishment system may occupy a great deal of space.
An exemplary embodiment of the present invention is a refurbishment system that includes at least one fluid feed tank, a refurbishment compartment, and at least one waste tank. A first fluid line connects the at least one fluid feed tank to the refurbishment compartment. A second fluid line connects the refurbishment compartment to the at least one waste tank.
A further exemplary embodiment of the present invention is a method for refurbishing a component. The method includes placing the component in a refurbishment compartment and delivering a first fluid to the refurbishment compartment. The method also includes removing the first fluid from the refurbishment compartment and delivering the first fluid to a first waste tank. The method further involves delivering a second fluid to the refurbishment compartment and removing the second fluid from the refurbishment compartment and delivering the second fluid to a second waste tank.
Another exemplary embodiment is a refurbishment system that includes at least one fluid feed tank, a refurbishment compartment having at least one fluid delivery element and a drain, and at least one waste tank. A fluid line connects the at least one fluid feed tank to the at least one fluid delivery element. The refurbishment system also includes a feed pump configured to deliver fluid through the fluid line. A recirculation line connects the refurbishment compartment drain to the at least one fluid delivery element and to the at least one waste tank. The refurbishment system also includes a waste pump configured to deliver fluid through the recirculation line.
Coated components are used in a variety of industries. Components may be coated with silicone coatings, polymers and other coatings. These coatings may serve different purposes such as protecting the component surface from damage or providing better surface chemistry for bonding. The components coated may be made of different materials. Metal components as well as composite components may have coatings. The components themselves may be made of polymers that are different from the coatings. Often times, coated components are expensive to replace and component refurbishment is used to reduce costs. Chemical cleaning and stripping is used to refurbish a component so that new coatings may be applied and the component returned to service. The chemicals used in the refurbishment process will largely depend on the type of coating and the type of component material.
Fluid feed tanks 12a-12c store the fluids used in the refurbishment process. Three fluid feed tanks 12a-12c are indicated in
Because aggressive solvents may be used in component recovery system 10, the system's tanks, lines, valves, and pumps must be constructed of materials that are resistant to aggressive solvents when used. Examples of suitable materials include stainless steel, Teflon, polyethylene and polypropylene.
Fluid feed lines 18a-18c allow fluid to flow from the fluid feed tanks 12a-12c, respectively, to refurbishment compartment 14 via feed line 20 and fluid delivery line 28. Each fluid feed line 18a-18c includes a valve 22a-22c configured to allow or prevent flow of the fluid in the feed tanks 12a-12c, respectively, into fluid line 20. Suitable valves 22a-22c include solenoid valves. Fluid line 20 allows fluid to flow from fluid feed lines 18a-18c to fluid delivery line 28 and refurbishment compartment 14. Fluid line 20 includes fluid delivery pump 24. Fluid delivery pump 24 is configured to pump fluid. Fluid enters fluid line 20 from fluid feed lines 18a-18c and is pumped through fluid line 20 towards fluid delivery line 28 by fluid delivery pump 24. Fluid line 20 also includes a valve 26 configured to allow or prevent flow of the fluid in fluid line 20 into fluid delivery line 28. Valve 26 may be a solenoid valve.
Fluid delivery line 28 connects fluid line 20 to refurbishment compartment 14. Fluid delivery line 28 provides one or more connections with refurbishment compartment 14. Fluid delivery line 28 may be plumbed directly into refurbishment compartment 14 or may connect to additional lines within refurbishment compartment 14. The embodiment illustrated in
Delivery element 30 may be connected directly to fluid delivery line 28 within refurbishment compartment 14 or delivery element 30 may connect to fluid delivery line 28 via additional lines within refurbishment compartment 14. Delivery element 30 direct fluids to the component to be cleaned inside refurbishment compartment 14. Delivery element 30 is located within refurbishment compartment 14 and configured to direct fluid so that fluid may interact with the component surfaces. The embodiment illustrated in
Components to be refurbished are placed within refurbishment compartment 14.
Refurbishment compartment 14 may include means for rotating or moving the components during refurbishment so that fluid directed by delivery element 30 contacts all component surfaces. One example of a rotating means is shaft 32, which may be motor driven. Components may be mounted or fastened to shaft 32 so that the component is rotated during the refurbishment operation. Rotation allows multiple component surfaces to come into contact with the fluids directed to the component by delivery element 30. In some embodiments, rotation may also allow component surfaces to submerge in fluid that has collected at the bottom of refurbishment compartment 14. Submerging the component provides additional contact between component surfaces and refurbishment fluids.
Refurbishment compartment 14 also includes a drain 34. Drain 34 is located in the lower portion of refurbishment compartment 14. Refurbishment compartment 14 may be designed to direct fluid towards drain 34. Drain 34 allows removal of fluid delivered to refurbishment compartment 14. Drain 34 may include a valve that can be closed to allow fluid to collect in the bottom portion of refurbishment compartment 14 to provide fluid in which the component may be submerged as described above. Drain 34 connects to recirculation line 36.
Recirculation line 36 connects refurbishment compartment drain 34 to fluid delivery line 28 and waste line 38. Recirculation line 36 includes recirculation pump 40. Recirculation pump 40 is configured to pump fluid. Recirculation pump 40 delivers fluid from drain 34 through recirculation line 36, fluid delivery line 28 and waste line 38. Recirculation line 36 also includes valve 42. Valve 42 allows or prevents the flow of fluid to fluid delivery line 28 or waste line 38 depending on the process step. During recirculation, valve 42 allows fluid to flow through recirculation line 36 to fluid delivery line 28 but not to waste line 38. During delivery to waste, valve 42 allows fluid to flow through recirculation line 36 to waste line 38 but not to fluid delivery line 28. To provide both recirculation and waste routes, valve 42 may be a three-way valve. Alternatively, two valves may be used. In one embodiment of the present invention, valve 42 may be a three-way solenoid valve.
Waste line 38 is connected to waste outlet lines 44a-44c. Waste outlet lines 44a-44c connect to waste tanks 16a-16c, respectively. Each waste tank 16a-16c has a separate waste outlet line 44a-44c.
The various operative steps of refurbishment using one embodiment of component recovery system 10 are demonstrated in
Recirculation mode may be employed for a predetermined amount of time. Depending on the fluid and its function, recirculation times may vary. Generally, fluid is recirculated until its function is completed or continued recirculation becomes suboptimal. For example, when the fluid delivered to refurbishment compartment 14 is a stripper, the fluid may be recirculated until it ceases to optimally strip coating from the component surfaces. A stripper ceases to function optimally once additional coating is no longer solubilized by the stripper or once the coating and bonding compounds are removed. Once the stripper is saturated with the coating stripped from the component surfaces, continued recirculation may be undesirable.
Waste fluid is collected and stored in waste tanks 16a-16c. Once a waste tank 16 is full, the contained waste fluid may be removed from waste tank 16 and prepared for disposal or reuse within component recovery system 10 or for other uses. In one embodiment, waste tanks 16a-16c may also serve as disposal tanks so that waste tanks 16a-16c may be removed from component recovery system 10, sent out for disposal, and new waste tanks 16a-16c may be added to component recovery system 10 to replace the tank sent for disposal.
In one embodiment of component recovery system 10, fluid waste collected in waste tanks 16a-16c may be reused by component recovery system 10. For example, waste stripper that is not saturated with the coating removed from the component(s) may be reused. Such waste fluid may be transferred to one of fluid feed tanks 12a-12c after it has been collected in one of waste tanks 16a-16c. Waste tanks 16a-16c and fluid feed tanks 12a-12c may be interchangeable so that waste tanks 16a-16c may be disconnected from waste outlet lines 44a-44c and connected to fluid feed lines 18a-18c for reuse.
Alternative embodiments of component recovery system 10 may include one or more baskets 50 or cages 52 (illustrated in
Alternatively, basket 50 may be replaced by cage 54, as illustrated in
The embodiments described above provide a system and method for component recovery with several advantages over the prior art. Refurbishment of a component can be performed while reducing the amounts of chemicals needed. A smaller amount of chemicals translates to cost savings in the purchasing and disposal of the chemicals. The process can be automated to reduce workers' exposure to harsh or toxic chemicals. Embodiments of the component recovery system may also reduce space requirements needed for refurbishment.
Although the present invention has been described with reference to exemplary embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.
The U.S. Government has a paid-up license in this invention and the right in limited circumstances to require the patent owner to license others on reasonable terms as provided for by the terms of Contract No. N00019-02-C-3003 awarded by the United States Navy.