Rock anchor and method of manufacture

An apparatus for manufacturing a rock anchor comprising a tendon composed of a plurality of strands, the tendon having at least one bulbous portion wherein all the strands in the bulbous portion are spaced apart from one another substantially around the periphery of each bulbous portion characterized in that the apparatus comprises at least two first clamp means spaced apart and movable relative to one another and able to clamp a tendon, and a clamp displacement means arranged to displace the first clamp means relatively towards one another so as to form a bulbous portion in a clamped tendon, each first clamp means comprising a hydraulic ram means bearing a plate arranged to clamp the tendon against an opposed plate, wherein there is also provided a tendon displacement means arranged to displace the tendon longitudinally relative to the first clamp means after a bulbous portion has been formed in the tendon, the tendon displacement means comprising a second clamp means arranged to grip the tendon for longitudinal displacement of the tendon, the second clamp means of the tendon displacement means being separate from the first clamp means used for formation of the bulbous portion.