Tube welding rod resistant to low stress abrasion

A tube welding rod resistant to low stress abrasion comprises a welded tube and a filler filling the welded tube. Components of the filler comprise macrocrystalline tungsten carbide particles, cast tungsten carbide particles and/or spherical cast tungsten carbide particles undergone surface carburization treatment, mechanically ground cast tungsten carbide particles, alloy powder, and an organic binder. The weight percentages of the components are: the macrocrystalline tungsten carbide particles being 10-50%, the cast tungsten carbide particles and/or spherical cast tungsten carbide particles undergone surface carburization treatment being 43-85%, the mechanically ground cast tungsten carbide particles being 0-20%, the alloy powder being 2-6%, and the organic binder being 0.2-1%. The welding rod improves the abrasion resistance performance of the hard-faced layer in the low stress working condition, and is particularly suitable for surface hardening of cone rolling bits and diamond bits.