Fluid lines are used to deliver a wide variety of working fluids, including fuel, brake fluid, hydraulic fluid, coolant, or the like in a wide variety of applications from automotive or aerospace uses to heavy machinery and more. In some applications, fluid lines are formed from metal tubing, such as a soft steel, copper, or aluminum. Connecting such metal tubing to a device can be accomplished by a variety of methods including welding and soldering. However, in some applications, such as where the use of an open flame is either undesirable or impractical, or such as when the resulting connection is desirably removable, connecting a fuel line to a device can be accomplished by using a fitting.
One well-known type of fitting customarily used for brake lines and fuel lines, for example, is a flared fitting 10, illustrated in FIG. 1. The flared fitting 10 includes a fitting body 12, and a fitting nut 14. The fitting body 12 defines a tapered end 16, a first threaded portion 18, and a second threaded portion 20. The fitting nut 14 defines an internal thread (not shown) configured to be threaded onto the first threaded portion 18 of the fitting body 12, and an axial bore (not shown) that allows that fitting nut 14 to be placed on a fluid line 22. The fluid line 22 includes a flared end 24 that increases a diameter of the fluid line 22 at an angle corresponding to an angle of the tapered end 16 of the fitting body 12.
To assemble the fitting 10, the second threaded portion 20 of the fitting body 12 is threaded into a device (not shown) that is to receive the fluid line 22. The fitting nut 14 is placed on the fluid line 22, generally before the flared end 24 is formed. A flaring operation is performed in order to form the flared end 24. The tapered end 16 of the fitting body 12 is then inserted into the flared end 24, and the fitting nut 14 is then threaded onto the first threaded portion 18 of the fitting body 12 in order to compress the flared end 24 of the fluid line 22 against the tapered end 16 of the fitting body 12. The resulting fitting 10 is robust against leaks, pressure-resistant, and is also resistant to strain and vibrational loads.
Various applications use tapers of different angles as appropriate. For example, brake lines, coolant lines, and fuel lines typically use a 45 degree taper, while hydraulic lines generally use a 37.5 degree taper. Various types of flared ends can also be formed. FIG. 2A illustrates a fluid line 22 with a single flared end 26, and FIG. 2B illustrates a fluid line 22 with a double flared end 28. In some applications, a single flared end 26 is sufficient, but a double flared end 28 can help prevent the fluid line from cracking when the fitting nut 14 is tightened down and can improve the strength and resilience of the connection.
The flaring operation, a forging operation that includes cold-working the fluid line 22, is performed via a flaring tool. Flaring tools customarily needed to be mounted on a rigid support like a vice clamp. This meant that a significant amount of workspace was needed to operate the tool, and that fluid lines could not generally be worked in situ, i.e., while the other end is attached to a vehicle brake or fluid system.
Flaring tools have been developed that operate in-line, i.e., without requiring disassembly of a fluid system in order to gain access to a fluid line and operate the flaring tool. In one example, hydraulic flaring tools have been developed that use hydraulic pressure and a piston to drive a die head into a fluid line mounted in a die adapter. Such devices can be operated by a user without being mounted on a support, but are expensive, costly, and complex to use.
Manual in-line flaring tools have also been developed. The ATD-5480 In-Line Flaring Tool available from ATD Tools, Inc., illustrated in FIG. 3, includes a bar clamp 30, a hex yoke 32, a center screw 34, and a flare adapter 36. The bar clamp includes cap screws 38 for clamping the bar clamp 30 together, and defines an external thread 40 with an axial bore. The hex yoke 32 has an axial bore 42 with an internal thread and a hex-shaped exterior 44. The flare adapter 36 is configured to be inserted into an end of a fluid line, and is operable to form a flared end thereof. The center screw 34 has an external thread configured to engage the inner thread of the hex yoke 32, and a hex-shaped head 46.
A fluid line is inserted into the axial bore of the bar clamp 30 with an end protruding from the external thread 40, and the cap screws 38 are tightened to clamp the fluid line therein. The flare adapter 36 is inserted into the end of the fluid line, and the hex yoke 32 is mounted over the external thread 40 of the bar clamp 30. The center screw 34 is then inserted into the internal thread of the hex yoke 32, and is threaded down to engage the flare adapter 36 and form a bubble on the fluid line. To thread the center screw 34 down, a user can grip the hex yoke 32 in one hand via a first wrench or grip, and can use a second wrench or grip on the head 46 of the center screw 34. The center screw 34 and hex yoke 32 can then be removed in order to remove the flare adapter 36. The hex yoke 32 and center screw 34 can then be replaced and threaded down in order to form the bubble into a double flared end.
While the ATD In-Line Flaring Tool allows a user to produce a flared end on a fluid line without disassembling a fluid system, the In-Line Flaring Tool may not be adapted for use in the close quarters or cramped environments generally found in the vicinity of fluid line connections. For example, the necessity of threading and unthreading the hex yoke from the bar clamp for each operation adds difficulty and complexity, especially in a process where a user may have an obstructed view of the operation. Additionally, the tool requires several independent parts that are sized to tight tolerances, and thus a kit accommodating a variety of sizes of fluid lines will be large and expensive.
Therefore, what is needed is a manual in-line flaring tool that is adapted for use in a cramped environment, that can be operated by a user with an obstructed view, and that is simple and easy to use.