Technical field of the invention This invention relates to a dump rope ferrule.

Background to the invention

The connection of heavy duty wire ropes to movable machinery such as open pit mining draglines used to be done by means of a wedge-style rope socket. However, the wedge-style rope socket has increasingly been replaced by a ferrule dump socket. The ferrule dump socket provides a shoulder in the socket to engage with a ferrule. The ferrule dump socket reduces change out time considerably and thereby increases machine up time significantly. The socket design is intended to prevent the ferrule from becoming wedged in and sticking, thereby allowing for easy removal of the ferrule and wire rope from the ferrule dump socket. A retaining bolt prevents the rope and ferrule from slipping laterally out of the socket. However, this configuration allows for movement of the ferrule in the socket. The movement of the ferrule in the socket allows impact damage and excessive rotation of the load bearing face of the ferrule, which causes peening, burring, mushrooming and/ or swelling of the ferrule. In addition, under extreme forces, the ferrule can become wedged in the socket housing, eliminating the quick change out features of this system. Further, during loading of the wire rope torque is generated as the rope tries to unlay. This can cause spinning of the ferrule in the socket increasing burring and deformation. These disadvantages are also dangerous and can cause catastrophic failure of the wire rope connection.

It is an object of the invention to provide a dump rope ferrule for use with a ferrule dump socket which does not suffer from the problems highlighted above. General description of the invention

According to the invention there is provided a ferrule for use with a ferrule dump socket, which ferrule includes:

a mild steel ferrule body; and

a ring of metal being harder than the metal of the ferrule body welded to the load bearing end of a ferrule after the ferrule has been pressed to its working diameter such that it forms a contiguous extension of the ferrule and provides a hard metal load bearing shoulder for the ferrule.

According to another aspect of the invention, there is provided a ferrule for use with a ferrule dump socket, which ferrule includes:

a mild steel ferrule body; and

a tapered stop welded onto the free end of a ferrule.

The stop may be a semi-circular wedge dimensioned to be welded onto the free end of a ferrule after the ferrule has been pressed to its working diameter such that it forms a contiguous extension of part of the ferrule and with one end of the wedge providing a stop wall perpendicular to the face of the free end of the ferrule.

The free end of a ferrule will be understood to be the end opposite the working end of the ferrule and pointing towards the end of the wire rope. The tapered stop engages with a retaining bolt transverse through the socket to prevent rotation of the ferrule. This automatically occurs when the rope is loaded for the first time due to the natural tendency for the rope to unlay, thereby rotating the tapered stop sufficiently to force the front face of the ferrule to securely engage with the socket shoulder and the tapered stop to prevent the socket from counter rotating.

The stop may also be provided with a hole there through to allow a shackle to be attached to the free end of the ferrule to facilitate handling of the wire rope during installation and removal. According to another aspect of the invention, there is provided a ferrule for use with a ferrule dump socket, which ferrule includes:

a mild steel ferrule body;

a ring of metal being harder than the metal of the ferrule body welded to the load bearing end of a ferrule after the ferrule has been pressed to its working diameter such that it forms a contiguous extension of the ferrule and provides a hard metal load bearing shoulder for the ferrule; and

a tapered stop welded onto the free end of a ferrule.

This invention also extends to a wire rope which is fitted with a ferrule as described above.

Detailed description of the invention

The invention is now described by way of example with reference to the accompanying photographs.

In the photographs:

Figure 1 shows a side view of a ferrule for use with a ferrule dump socket showing how it is to be assembled after pressing, in accordance with the invention;

Figure 2 shows a side view of the free end of the ferrule with a stop welded onto the free end of the ferrule after being pressed, in accordance with the invention; and

Figure 3 shows a side view of the ferrule showing a hard metal ring welded onto the other end of the ferrule after being pressed, in accordance with the invention.

Referring now to the drawings, the ferrule dump socket, in accordance with the invention, is generally indicated by reference numeral 10.

The ferrule 10 includes a mild steel ferrule body 12 and a ring of metal 14 being harder than the metal of the ferrule body welded to the load bearing end of a ferrule after the ferrule has been pressed to its working diameter such that it forms a contiguous extension of the ferrule and provides a hard metal load bearing shoulder for the ferrule. The ferrule 10 further includes a stop 16 welded onto the free end of the ferrule. The stop 16 is a semi-circular wedge dimensioned to be welded onto the free end of the ferrule 0 after the ferrule has been pressed to its working diameter such that it forms a contiguous extension of part of the ferrule and with one end of the wedge providing a curved taper 21 which will locate under the ferrule securing bolt provided with the socket and a stop wall 18 perpendicular to the face of the free end of the ferrule. In operation the curved taper 21 will rotate under the bolt and force the ferrule and socket shoulder faces together to prevent any lateral movement between them and prevent the adverse hammering and rotational effects from distorting the ferrule. The stop wall will also prevent the ferrule from counter rotating should the load on the rope be reduced suddenly and with enough energy to dislodge the curved taper. The stop 16 is further provided with a hole there through to allow a shackle (not shown) to be attached to the free end of the ferrule to facilitate handling of the wire rope.

In this example, the ferrule body 12 is of EN3A steel and the ring of metal 14 and the stop 16 is of EN9 steel.

It shall be understood that the example is provided for illustrating the invention further and to assist a person skilled in the art with understanding the invention and is not meant to be construed as unduly limiting the reasonable scope of the invention.