Chain having longitudinal stiffness used with hauling and cutting equipment

Hauling and cutting equipment, comprising a conveyor trough having a longitudinal side wall on each side, a support rail structure on at least one side of said trough having a chain guide groove therealong, a link chain extending in said chain guide groove along said support structure, a winning machine overlying said trough and guided on said rail structure, a drive for said winning machine including at least one chain wheel on said winning machine having teeth engaging in said link chain and having vertical link receiving divisions between said teeth, said link chain comprising a round link chain having alternate long horizontal links and short vertical links of a shorter length than said horizontal links, a clear division of said vertical links being substantially double the link diameter of said horizontal links except for a predetermined amount of play spacing, the engagement division of said chain wheel being substantially equal to the length of said vertical links, said vertical links have link arcs with an inside radius corresponding in the contact region with said horizontal link to the inside radius of the link arc of said horizontal link.