GB1022943A - Improved pile driving mandrel - Google Patents

Abstract

1,022,943. Pile driving mandrels. F. RUSCHE. June 2, 1964 [Nov. 15, 1963], No. 22787/64. Heading E1H. A pile driving mandrel comprises a tube 10 provided with head and foot end plates 12, 14; an outwardly expressable surface 22 carrying lugs 24, means 36 for biasing the surface to a retracted position, means 42 disposed within tube 10 and operable from outside the tube for expressing surface 22 to enable lugs 24 to engage a shell (not shown), a rigid supporting structure for means 42 extending within the tube and resilient means interposed under compression between the structure and at least one of the end plates. As shown, the supporting structure extends along the length of the tube and comprises a square tube 44 welded to four angle irons 46. At its lower end 56 tube 44 is rounded and enters a hole and is welded in end plate 84. Relative rotational movement between plates 84 and 14 is prevented by studs 88. Between plate 84 and foot end plate 14 are disposed discs 94 forming a resilient pad 60. Each disc comprises a matrix of elastomeric material reinforced with fabric. The top end of the supporting structure is welded to a plate 80 and a pad 60 is disposed between plate 80 and head end plate 12. A square tube 82 is welded to the lower face of plate 12 and square tube 44 telescopes into it to prevent relative rotation. The expressing means comprises inflatable hoses 42 which communicate with a manifold 48 to which air is conducted by a fitting 50. Figs 6 and 8 (not shown) illustrate two mandrel sections coupled together as described in Specification 1,002,741, with resilient pads 60 disposed one in each section between the appropriate head or foot end plate and the end plate of the supporting structure.