Patent Publication Number: US-10316378-B2

Title: Apparatus for quenching

Description:
This application is a U.S. National Phase application of PCT International Application No. PCT/GB2014/053122, filed Oct. 17, 2014, which claims the benefit of GB 1318462.7, filed Oct. 18, 2013, both of which are incorporated by reference herein. 
     TECHNICAL FIELD OF THE INVENTION 
     This invention relates to quenching components and, more particularly, to a quenching system, a quenching agent delivery apparatus and a method of quenching a component. 
     BACKGROUND TO THE INVENTION 
     Quenching is a well known technique used to rapidly cool a machined work piece. Quenching is used readily in the manufacture of metal work pieces. A quenching process may be used to cool a metal work piece after the work piece has been heated to a high temperature for shaping or manipulating it in some way, for example to strengthen it. 
     In a known quenching system, a quenching tank is filled with a quenching agent, for example water or oil. A component to be quenched is then submerged in the quenching agent in the quenching tank so that the surface of the component is in contact with the quenching agent. 
     Some components that need to be quenched are hollow and, to ensure that inner surfaces of the component are quenched along with the outer surface of the component, it is necessary for the quenching agent to come into contact with the inner surface. 
     It is important that, when a component is placed in the quenching agent, the quenching agent comes into contact with the entire inner surface of the component. If the portion of a surface of a component is not quenched following a heat treatment process, or if a portion of the surface is quenched less than another portion of the surface, then there can be uneven quenching of the component. 
     SUMMARY OF INVENTION 
     According to a first aspect, the present invention provides a quenching agent delivery apparatus for delivering a quenching agent to a component to be quenched, the apparatus comprising an inlet through which the quenching agent is configured to be delivered into the apparatus; a first outlet configured to deliver quenching agent in a first direction to an inner surface of the component; and a second outlet configured to deliver quenching agent in a second direction to an inner surface of the component. The second direction may be at an angle of approximately 45 degrees with respect to the first direction. 
     A deflector may be located within the apparatus configured to deflect a proportion of the quenching agent entering the apparatus through the inlet to exit the apparatus through the second outlet. 
     The deflector may be configured to allow a proportion of the quenching agent entering the apparatus through the inlet to be delivered to, and exit the apparatus through, the first outlet. 
     The deflector may comprise at least one aperture, the at least one aperture being sized and shaped to allow a predetermined amount of quenching agent to pass therethrough. The at least one aperture may be configured to allow between around 15 percent and 30 percent of quenching agent flowing into the apparatus via the inlet to be delivered to, and exit the apparatus through, the first outlet. The at least one aperture may comprise a single circular aperture. 
     The delivery apparatus may be elongate and may define a longitudinal axis. The deflector may be inclined at an angle of around 45 degrees with respect to the longitudinal axis. 
     A seal may be formed around a periphery of the apparatus. The seal may be configured such that, when the apparatus is installed in a component, the amount of quenching agent able to flow between the apparatus and component is restricted. 
     According to a second aspect, the present invention provides a quenching system comprising: a quenching tank configured to contain a quenching agent; a conduit configured to transport the quenching agent; and a quenching agent delivery apparatus according to any of the preceding claims, the quenching agent delivery apparatus being connected to a first end of the conduit. 
     The quenching agent delivery apparatus may be configured to remain stationary relative to the component during quenching. 
     The delivery apparatus may comprise a seal sized to allow a predetermined amount of quenching agent to pass between the component and the delivery apparatus. The delivery apparatus may further comprise a pump for pumping said quenching agent through the conduit. 
     The delivery apparatus may comprise a coupler for coupling the conduit between the pump and the quenching agent delivery apparatus. 
     According to a third aspect, the present invention provides a method of quenching a component, the method comprising: inserting at least partially into the component a quenching agent delivery apparatus, the delivery apparatus having a first outlet and a second outlet; connecting the delivery apparatus to a conduit through which quenching agent is configured to flow; placing the component and the delivery apparatus into a quenching tank containing quenching agent; and pumping the quenching agent through the conduit and delivery apparatus into the component via the first outlet and the second outlet. 
     Other advantageous features will be apparent from the following description. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Embodiments of the invention will now be described, strictly by way of example only, with reference to the accompanying drawings, of which: 
         FIG. 1  is a schematic drawing of a quenching system constructed in accordance with an embodiment of the present invention; 
         FIG. 2  is a sectional view of an apparatus for delivering quenching agent to a component to be quenched, constructed in accordance with an embodiment of the present invention; 
         FIGS. 3A to 3G  are sectional views of the apparatus of  FIG. 2 , showing various configurations of a deflector plate; and 
         FIG. 4  is a schematic diagram of a docking system for use in the quenching system of  FIG. 1 . 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     Referring to the drawings,  FIG. 1  shows a quenching system, labeled generally as  100 , which includes a quenching tank  102  containing a quenching agent  104 . A pump  106  is connected to the quenching tank  102  via a hose or conduit  108 . A delivery conduit  110  is connected at a first end to the pump  106  and at a second end to a docking port  112 . The docking port  112 , which will be described in more detail below, is configured to be received by and dock with a docking socket  114  so as to allow quenching agent  104  to flow into a component to be quenched  116 . The docking socket  114  is connected via a delivery pipe or conduit  118  which in turn is connected to a quenching agent delivery apparatus  120 . The apparatus  120  for delivering quenching agent to the component  116  is in the form of a nozzle and will be described in greater detail below. The delivery apparatus  120  is inserted into the component  116  through an aperture or opening  122  in the component. 
     The component  116  is shown in  FIG. 1  as a generally rectangular component having a generally L-shaped cavity formed therein. The component to be quenched  116  may be a generally tubular component which is used in an aircraft landing gear. However, it will be appreciated that any other component that requires quenching could be quenched using this system. 
     While the present invention is particularly advantageous for quenching components having a generally L-shaped cavity, it will be appreciated that the invention could be used with components of any shape which are hollow or have a cavity formed therein and an opening through which quenching agent can pass in order to reach internal surfaces of the component. 
     In the exemplary system  100  shown in  FIG. 1 , in order to carry out the quenching process, the component  116 , the delivery apparatus  120 , the delivery pipe  118  and the docking socket  114  are lowered towards the quenching agent  104  in the quenching tank  102 . The system  100  is arranged such that the docking socket  114  and the docking port  112  are completely submerged in the quenching agent  104  after they engage one another. It will be appreciated that additional components (not shown) will be required to lower the component into the quenching tank. For example, a crane, counterweight and pulley system might be used to lower the component into, and raise the component out of, the quenching tank. Furthermore, additional components (not shown) might be used to align the component and to align the docking socket  114  with the docking port  112  as the component is lowered into the quenching tank. 
     In use, the quenching agent delivery apparatus  120  is partially inserted into the component to be quenched  116 , and connected in position in the manner described below with reference to  FIG. 2 . The delivery apparatus  120  is connected to the delivery pipe  118  which, in turn, is connected to the docking socket  114 . When the component  116  undergoes its heat treatment prior to being quenched, the delivery apparatus  120 , the delivery hose  118  and the docking socket  114 , which are connected to the component, also undergo the heat treatment. By connecting the delivery apparatus  120  to the component  116  prior to the heat treatment process, the time taken to move the component from the heat treatment furnace to the quenching tank  102  can be kept as short as possible. Since the delivery apparatus  120 , the delivery pipe  118  and the docking socket  114  are already connected to the component  116 , immediately following the heat treatment process, the heat treated component can be lowered into the quenching agent  104  in the quenching tank  102 . As the component  116  is lowered into the quenching tank  102 , the docking socket  114  engages with the docking port  112 , and the relative configurations of the docking socket and port assist the correct alignment. As the component  116  is submerged into the quenching agent  104 , the engaged docking socket  114  and docking port  112  are also lowered into the quenching agent. The pump  106  is activated as the delivery apparatus  120  is lowered into the quenching agent  104 . Ideally, the flow of quenching agent  104  via the pump  106  begins as soon as the component  116  comes into contact with the quenching agent. In this way, the flow of quenching agent  104  internally and externally with respect to the component  116  is balanced during immersion of the component. 
     Consequently, the heat transfer coefficients of the internal and external surfaces of the component  116  are balanced as the component is immersed. The pump  106  pumps quenching agent  104  from the quenching tank  102 , via the hose  110 , through the docking port  112  and docking socket  114 , through the delivery pipe  118 , and into the delivery apparatus  120 . The flow of quenching agent  104  through and out of the delivery apparatus  120  will now be discussed in greater detail, with reference to  FIG. 2 . 
       FIG. 2  is a cross sectional view of the quenching agent delivery apparatus  120 , which takes the form of a nozzle, and allows quenching agent to be delivered to internal surfaces of a hollow component or a component having a cavity formed therein. 
     The delivery apparatus  120  is generally tubular in shape, defining a longitudinal axis A. The delivery apparatus  120  has an inlet  202  via which quenching agent  104  is able to flow from the delivery pipe  118  (see  FIG. 1 ) into the delivery apparatus. A first outlet  204  is formed at an end of the delivery apparatus  120  opposite to the inlet  202 . A second outlet  206  is formed in a wall of the delivery apparatus  120 . The first outlet  204  and the second outlet  206  allow quenching agent  104  to flow out of the delivery apparatus  120  in two different directions, namely in a first direction substantially along the longitudinal axis A (via the first outlet  204 ) and in a second direction at an angle of around 45 degrees to around 90 degrees relative to the longitudinal axis A (via the second outlet  206 ). 
     A deflector  208  is located within the delivery apparatus  120  and is arranged to deflect a portion of quenching agent  104  flowing through the delivery apparatus through the second outlet  206 . One or more apertures  210  formed in the deflector  208  allow a portion of quenching agent  104  flowing through the delivery apparatus  120  to flow beyond the deflector to the first outlet  204 . The size of the aperture  210  formed in the deflector  208  or, where a plurality of apertures are formed in the deflector, the size and configuration of the plurality of apertures, can be selected to allow a particular proportion of quenching agent  104  flowing into the delivery apparatus  120  to flow through the deflector  208  to the first outlet  204 . Some possible configurations of apertures  210  formed in the deflector  208  will be discussed in more detail with reference to  FIGS. 3A to 3G  below. 
     As will be apparent from  FIG. 2 , the diameter of the first outlet  204  is smaller than the diameter of the inlet  202  of the delivery apparatus  120 . The diameters or sizes of the first outlet  204  and the second outlet  206  are chosen to increase or decrease the speed of the quenching agent  104  leaving the delivery apparatus via the outlets  204 ,  206 . In other words, reducing the diameter of the outlet  204  will result in an increase of the speed at which quenching agent  104  exits the delivery apparatus  120  via the first outlet. If the first outlet  204  has a larger diameter, the quenching agent  104  would exit the delivery apparatus  120  at a relatively lower speed. 
     In some embodiments, a seal  212  is formed around the circumference of the delivery apparatus  120 . The seal  212  is positioned such that when the end of the delivery apparatus  120  at which the first and second outlets  204 ,  206  are located is inserted through the opening  122  in the component  116  to be quenched the seal engages the component around the opening and restricts the amount of quenching agent  104  able to leave the component through the opening. The amount of quenching agent  104  able to leave the component  116  via the opening  122  is selected to ensure that a sufficient pressure of quenching agent within the component is maintained. In other words, if it is desirable to have a high pressure of quenching agent  104  within the cavity of the component  116  during quenching, then a relatively larger seal  212  is fitted to the delivery apparatus  120 , thereby restricting the amount of quenching agent able to exit the component  116  via the opening  122  around the outside of the delivery apparatus. However, if a relatively lower pressure of quenching agent is required within the cavity of the component  116  during quenching, then a relatively smaller seal  212  is fitted to the delivery apparatus  120 , thereby allowing more quenching agent  104  to leave the cavity of the component via the opening through which the delivery apparatus is inserted. In other embodiments, the delivery apparatus  120  is not provided with a seal. In embodiments where no seal is provided, the pressure of the quenching agent  104  within the component  116  can be maintained at a desired level by increasing or decreasing as required the flow rate of quenching agent injected into the component  116 . A further advantage of the component not having a seal is that hot quenching agent  104  from within the component  116  can more easily exit the component via the opening  122 , thereby reducing the temperature of quenching agent within the component. 
     The delivery apparatus  120  may, in some embodiments, include an external deflector  124 , which is formed around the circumference of the apparatus  120 , and serves to deflect quenching agent  104  exiting the component  116  via the opening  122  downwards into the quenching tank  102 . If quenching agent  104  is injected into the component  116  at a fast rate. then the hot quenching agent exiting the component will also be travelling at a fast rate. Therefore, the provision of the external deflector  124  reduces the chance of damage occurring to nearby equipment, and injuries occurring to users of the system  100  as a result of spray or splashes of hot quenching agent. 
     As mentioned above with reference to  FIG. 2 , the deflector  208  may be formed with one or more apertures formed therein in a number of different configurations.  FIGS. 3A to 3G  show various configurations of apertures that may be formed in the deflector plate. Each of  FIGS. 3A to 3G  is a sectional view through the delivery apparatus  210 , along the direction of the longitudinal axis A. The deflector  208  is shown transparent for clarity and, therefore, the first outlet  204  is visible. In  FIGS. 3A to 3G , the delivery apparatus  120  is oriented as it is shown in  FIG. 2 , with the second outlet  206  (not shown in  FIGS. 3A to 3G ) at the top of the delivery apparatus. 
     In  FIG. 3A , a single aperture  210  is formed at an edge at the bottom of the deflector  208 . The area of the aperture  210  forms 20% of the total circular cross sectional area of the deflector  208 . 
     In  FIG. 3B , a single aperture  212  is formed away from the edges of the deflector  208 . The area of the aperture  212  forms 20% of the total circular cross sectional area of the deflector  208 . 
     In  FIG. 3C , a plurality of substantially circular apertures  214  are formed in an array in the deflector  208 . The total area of the apertures  214  forms 20% of the total cross sectional area of the deflector  208 . In the arrangement shown in  FIG. 3C , the array is formed of twelve circular apertures  214  formed in a first row of five apertures, a second row of four apertures, and a third row of three apertures. However, other arrangements would be envisaged by those skilled in the art. 
     In  FIG. 3D , a plurality of three elongate apertures  216  are formed in the deflector  208 . The apertures  216 , in this arrangement, are vertical apertures, and are arranged adjacent to one another. The total area of the apertures  216  forms 15% of the total circular cross sectional area of the deflector  208 . 
     In  FIG. 3E , a plurality of elongate apertures  218  are formed in the deflector  208 . The apertures  218  in this arrangement are similar to the apertures  216  shown in  FIG. 3D . However, in  FIG. 3E , the apertures  218  are longer than the apertures  216  of  FIG. 3D . Accordingly, the total area of the apertures  218  forms 20% of the total circular cross sectional area of the deflector  208 . 
     In  FIG. 3F , a plurality of apertures  220  are formed in the deflector  208 . The apertures  220  are similar in shape to the apertures shown in  FIG. 3E . However, in the arrangement shown in  FIG. 3F , four elongate apertures  220  are formed in the deflector  208 . The total area of the apertures  220  forms 30% of the total circular cross sectional area of the deflector  208 . 
     In  FIG. 3G , a plurality of apertures  220  are formed in the deflector  208 . In this arrangement, two elongate horizontally-oriented apertures  222  are formed in the deflector  208 , one above the other. The total area of the apertures  222  forms 20% of the total circular cross sectional area of the deflector  208 . 
     In  FIGS. 3A to 3G , the apertures  210 ,  212 ,  214 ,  216 ,  218 ,  220 ,  222  are shown having particular shapes, orientations and sizes. Where multiple apertures are formed in the deflector  208 , they are shown having particular arrangements and configurations. It will be appreciated by those skilled in the art that these are merely examples of possible configurations of apertures that could be formed in the deflector  208  in order to achieve the desired effect. For example, where it is desirable to allow 20% of the quenching agent  104  reaching the deflector  208  to pass through the apertures, a large number of alternative arrangements of apertures could be used to achieve the required through-flow of quenching agent. The particular arrangements of apertures described above are advantageous as they allow the desired amount of quenching agent  104  to pass through the deflector  208 , while ensuring that the quenching agent continues to flow relatively uniformly after it has passed through the deflector  208 . If quenching agent  104  passes through the deflector  208  and fails to flow relatively uniformly along the delivery apparatus  120 , then there exists the risk that some of the quenching agent  104  in the delivery apparatus  120  will remain stationary, resulting in inefficient heat removal from either the component being quenched  116  or from the delivery apparatus  120  itself. If heat is not removed evenly and in a timely manner from the component  116  or the delivery apparatus  120  by the quenching agent  104 , then the risk of uneven quenching of the component is increased. 
     In the embodiments shown in  FIGS. 3A to 3G , the apertures in the deflector  208  form between 15% and 30% of the total circular cross sectional area of the deflector. The percentage of the total circular cross sectional area of the deflector formed by apertures can be chosen depending on the amount of quenching agent  104  desired to exit the delivery apparatus  120  via the first outlet  204  and via the second outlet  206 . For example. if a larger percentage of the quenching agent  104  is required to exit the delivery apparatus  120  via the first outlet  204 , then a deflector having a greater number of apertures, and/or larger apertures, can be used. 
     A deflector having a single round aperture allows a through-flow of quenching agent  104  which reaches a steady state in the delivery apparatus  120  in the shortest time. Thus, in some embodiments, a deflector  208  is provided with a single circular aperture. 
       FIG. 4  shows a docking system  400  which includes the docking port  112  and the docking socket  114 . The docking system  400  acts as a coupler and serves to couple the pump  106  to the delivery apparatus  120  via the delivery conduit  110  and the delivery pipe  118 . As is discussed above with reference to  FIG. 1 , the docking port  112  is connected to a delivery conduit  110 , through which quenching agent  104  can be pumped by the pump  106 . The docking socket  114  is connected to the delivery apparatus  120  via the delivery pipe  118 . 
     The docking socket  114  includes a funnel portion  402  having a first end  402   a , which connects to the delivery pipe  118 , and a second end  402   b , which is larger than the first end, and through which the docking port  112  can be received. Thus, the docking socket  114  is generally frusto-conical in shape. The relatively larger opening  402   b  of the docking socket  114  serves to allow easier engagement with the docking port  112 . As the docking socket  114  is lowered onto the docking port  112 , the funnel portion of the docking socket guides the docking port into the docking socket so that, even if the port and socket are not perfectly aligned, the port is guided into the correct alignment. 
     The automatic aligning of the docking socket  114  with the docking port  112  reduces the need of human intervention in connecting the docking port and the docking socket when the component  116  is lowered into the quenching tank  102 . Thus, the time taken to transfer the component  116  from heat treatment apparatus to the quenching tank can be kept as short as possible. 
     So far, the invention has been described in terms of individual embodiments. However, those skilled in the art will appreciate that various embodiments of the invention, or features from one or more embodiments, may be combined as required. It will be appreciated that various modifications may be made to these embodiments without departing from the scope of the invention, which is defined by the appended claims.