Manufacturing technology of R4 grade mooring cable used on deep sea drilling platform

Abstract

The invention discloses a manufacturing technology of an R4 grade mooring cable used on a deep sea drilling platform. The manufacturing technology comprises steps as follows: blanking, heating, ring making, flash welding, burr removing, ledge pressing, quenching and tempering, tension testing, surface polishing, non-destructive flaw testing, packing, dip coating and shipping, wherein during heating, the fine grain steel granularity is required to be maintained to be higher than three grades; the temperature difference is controlled to be plus or minus 2 DEG C; during ring making, welded junctions are spaced for 1-3 mm, the angle is 3-4 degrees, and the alignment tolerance is 0.3 mm; the burr removing precision is smaller than 3%; the difference of the reshaping size of a pressed ledge is controlled to be plus or minus 0.2 mm; a ledge is strengthened and not symmetric; and the ledge length difference is plus or minus 0.2 mm. The marine mooring cable manufactured with the manufacturing technology method has the effects of high strength and toughness, corrosion resistance and fatigue resistance.

Description

technical field [0001] The invention relates to an R4 grade mooring anchor chain used in a deep sea mooring system, in particular to a production process for an R4 grade mooring chain of a deep sea drilling platform. Background technique [0002] Marine mooring chain products are mainly used in floating production systems for offshore oil development, semi-submersible drilling platforms, single-point mooring structures, floating production and storage, and other marine development facilities. Since the chain is immersed in seawater for a long time, the steel used for mooring chains is required not only to have high strength and toughness, but also to have properties such as seawater corrosion resistance, fatigue resistance, and wear resistance. In the chain-making process of mooring chains, the rods are flash-welded to make a thousand-meter-long chain, and the whole chain is then subjected to quenching and tempering heat treatment. Quenching and tempering cracks are very ea...

AI Technical Summary

Problems solved by technology

Quenching and tempering crack defects are easily produced on the surface and welds of large-scale chains. Once such defects occur, the cracked links must be removed from the entire chain and remade, which will greatly increase energy consumption and reduce production. efficiency

In addition, during the welding process, the burning and accumulation of main elements such as C, Si, Mn, etc. at the weld will reduce the mechanical properties of the weld

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