System for propelling a coil clad hose and method thereof

A system for axially propelling a hose, comprising:

• a system housing;
• a tractor element disposed in the system housing and including:
• a tractor housing rotatably supported in the system housing for rotation of the tractor housing about an axis through the tractor housing, the tractor housing having an axial through-bore;
• a first protrusion roller rotatably fastened to the tractor housing at a non-perpendicular angle with respect to a first direction along the axial through bore and extending through the tractor housing into the through-bore;
• a second protrusion roller circumferentially adjacent to the first protrusion roller rotatably fastened to the tractor housing at a non-perpendicular angle with respect to the axial through bore and at a different angle with respect to the first direction along the axial through bore than the fastened angle of the first protrusion roller, the second protrusion roller extending through the tractor housing into the through-bore, wherein adjacent first and second protrusion rollers are a pair that extends through a common opening in the tractor housing;
• a hose assembly configured to extend into the through-bore, wherein the hose assembly has a helical coil disposed about a hose;
• and,
• as the tractor housing is rotated by an actuator in a first rotational direction about the axis:
• the first protrusion roller rolls along a first flank portion of the coil and exerts a first displacement force on the coil;
• and,
• the hose assembly reacts to the first displacement force by displacing in a first axial direction;
• as the tractor housing is rotated by the actuator in a second rotational direction opposite the first rotational direction, the second protrusion roller rolls along a second flank portion of the coil different from and circumferentially spaced from the first flank portion of the coil and exerts a second axial displacement force on the coil.

An apparatus for axially propelling a coil clad hose assembly having a substantially helical metal wire coil disposed about a high pressure hose, the apparatus comprising:

• an outer housing;
• a cylindrical tractor element disposed in the housing, wherein the cylindrical tractor element includes:
• a rotatable cylindrical tractor housing with a through bore for receiving the coil clad hose assembly therein;
• and
• a plurality of axially spaced pairs of first and second protrusion rollers rotatably fastened to the tractor housing, each protrusion roller extending through the tractor housing into the through bore, wherein the first protrusion rollers are each fastened at non-perpendicular angles with respect to a first direction along the axial through bore and the second protrusion rollers are each fastened at different non-perpendicular angles with respect to the first direction along the axial through bore and wherein each second protrusion roller is circumferentially spaced from and adjacent one of the first protrusion rollers so as to engage different flank portions of the coil on the hose when the coil clad hose assembly is inserted into the through bore, and wherein each pair extends through a common opening into the tractor housing;
• and
• an actuator within the outer housing mounted adjacent the cylindrical tractor housing for rotating the tractor housing with respect to the outer housing to drive the coil clad hose assembly axially through the cylindrical tractor housing.