Abstract: A chain comprises links formed from bar stock having a specific cross-section. In a preferred embodiment, which is a chain of 16 mm size, the cross-section comprises four convex arcuate sides (10a), (10b), (10c) and (10d), each of which has a radius of curvature at least 10% greater than the chain size (i.e. at least 10% greater than 8 mm) and preferably at least 15% greater than the chain size. In this way, a chain is produced which has the profile which is similar to the profile attained by the chain after a significant period of wear, involving a significant increase in the surface-to-surface contact between adjacent links, reducing the effective wear rate, and reducing the rate of effective lengthening of the chain due to wear.

Abstract: A steel alloy for fabricating into chain links particularly for a mining chain having a composition including nickel in the range of 0.3 to 1.5%, particularly 1%, chromium in the range of 0.2 to 1.0%, particularly 0.5%, molybdenum in the range of 0.1 to 1.0%, particularly 0.75%, carbon in the range of 0.15 to 0.28%, particularly 0.23%, vanadium in the range of 0.05 to 0.2%, particularly 0.1%, and the balance iron. The steel alloy enables the fabrication of mining chain having an acceptable stress corrosion resistance to aggressive conditions likely to be encountered in mining without sacrificing hardness and strength in comparison with a conventional composition steel chain.

Abstract: A shackle connector 8 for a scraper chain conveyor assembly in which the shackle connectors 8 are interlinked with chains 2,4, bolted to scraper bars 6 and formed with an enlarged portion or pad 20 serving slidably to guide the assembly relative to the inner profile of an associated trough or pan. The shackle connectors 8 are selectively heat treated such that the surface or surface and sub-surface hardness value of the enlarged portions or pads 20 is in the range of approximately 280-380 (preferably 340-380) Brinel Hardness and the remainder of the shackle connector, or at least crown portions 10, 12, have a surface or a surface and sub-surface hardness value in the range of approximately 380-550 (preferably 440-500) Brinel hardness and such that the mechanical properties of the shackle connector are enhanced while any propensity towards the propagation of frictionally induced surface cracks is resisted.