Hauling beam and a hauling transporter

A hauling transporter comprising a frame,

• at least one hauling beam supported on the frame and comprising:
• at least two parallel slats having two parallel sides and two opposite ends, the at least two parallel slats being set at a distance from each other so that here is a gap between the adjacent parallel sides,
• a support beam set on the at least two parallel slats so that the slats and the support beam are configured to be movable longitudinally with respect to each other,
• a support arm movably attached to the support beam,
• an axle and a roller coaxially attached to the support arm,
• a wedge placed between the at least two parallel slats and having a groove for the roller and a wedge tongue for connecting to the axle upon longitudinal movement of the at least two parallel slats and the support beam,
• a spring retainer having a body with at least one mounting block attached to at least one of the at least two parallel slats, a slide mounted on the body and a spring retained between the slide and a detent on the body, wherein the slide is attached to the support beam, a chain running as a loop around chain sprockets at each end of the hauling beam, one end of the chain being connected to the slide and one end connected to the body of the spring retainer, and an actuator configured to move one of the sprockets in a longitudinal direction of the chain, and
• a step beam supported on the frame and configured to be movable longitudinally along the frame parallel to the hauling beam.