A complete theory is given of force build-up in cables pulled in pipes, beyond “classic” Rifenburg equations, including large radius bends and/or pushing the cable, following the outside facing wall of the bend. Also 3D-bends are treated. This is used in software, where besides gravity friction and capstan effect also “waving” the cable during pushing and the effect of cable stiffness in bends and undulations in the pipe are taken into account. Not only pulling and pushing, also other installation techniques are evaluated, like those making use of fluid propelling (blowing and floating).
Willem Griffioen, Damien Plumettaz, Valery Naula