Casting material and manufacturing method of planet carrier for jack-up offshore platform lifting gear box

Abstract

The invention relates to a large-ratio and large-torque planet carrier steel casting material used for a self-elevating offshore platform lifting gear box and a production method. The material comprises the following chemical components in mass by percentage: 0.28 to 0.35 percent of C, 0.20 to 0.35 percent of Si, 0.65 to 0.85 percent of Mn, less than or equal to 0.030 percent of S, less than or equal to 0.030 percent of P, 0.85 to 0.95 percent of Cr, 0.20 to 0.26 percent of Mo, 0.04 to 0.08 percent of V, and 0.02 to 0.06 percent of Ti; and the remaining content is Fe. The planet carrier steel casting material has the advantages that the working procedures are simplified, connection areas between a pin, an upper flange and a lower flange are subject to smooth transition by circular angles, so that the anti damage capacity and the working stability are enhanced; the traditional casting process of 'progressive solidification' by using the casting structure is changed, external chill is arranged at a specific area to change the earliest solidification area, the solidification feeding of the casting can be changed by changing a feeding channel chain, the connection areas between the pin, the upper flange and the lower flange are tightly, the stress of shrinkage solidification is greatly reduced, and cracks are avoided.

Description

technical field [0001] The invention relates to a planetary frame material for a self-elevating marine platform lifting gear box with a large speed ratio and super large torque, which can be solved by adopting integral casting instead of split forging and welding to see internal performance degradation and poor low-temperature impact toughness, as well as pins and pins in the casting process. The invention discloses a material and a manufacturing method of crack defects in the connection area of ​​upper and lower flanges, belonging to the field of cast steel material manufacturing. Background technique [0002] In foreign countries, the flanges at the upper and lower ends and the three parts of the column pin are forged into blanks, welded after machining, and finally finished. The specific manufacturing process is: scrap steel raw material _ casting ingot _ forging molding _ parts blank _ rough processing _ welding _ finishing processing _ final product. Its shortcomings: ...

AI Technical Summary

Problems solved by technology

Its shortcomings: the manufacturing process is complicated, the processing cycle is long, the production cost is high, and the utilization rate of materials is low. Areas are prone to damage during use

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