Cranes and their jibs

Abstract

The invention discloses a crane and an arm frame thereof. At least one lightening hole is formed in a perforable region of the side wall surface of the arm frame, minimum distances between the left outline of the perforable region and the left outline of the side wall surface of the arm frame and between the right outline of the perforable region and the right outline of the side wall surface of the arm frame are respectively 1 / 10-1 / 9 of the maximum longitudinal size of the side wall surface of the arm frame; minimum distances between the upper outline of the perforable region and the upper outline of the side wall surface of the arm frame and between the lower outline of the perforable region and the lower outline of the side wall surface of the arm frame are respectively 1 / 4-1 / 3 of the maximum transverse size of the side wall surface of the arm frame; the maximum transverse size and the maximum longitudinal size of the lightening hole in the side wall surface of the arm frame are respectively 1 / 4-1 / 3 of the maximum transverse size of the side wall surface of the arm frame, and 2-3 times the maximum transverse size of the side wall surface of the arm frame; the sum of the sectional areas of the lightening hole is not more than 35-40 percent of the area of the perforable region. According to the arm frame in the crane, on the premise of meeting the requirement of the fatigue service life, service lives of all parts trend to be consistent, the weight of the arm frame can be lightened, and the performance of the arm frame is improved.

Description

technical field [0001] The invention relates to hoisting machinery, in particular to a crane and its jib Background technique [0002] The long jib is an important part of many large crane products, and it is the key structure for the crane to work normally. However, in actual work, due to frequent use of the jib, individual parts (parts) of the jib are prone to fatigue damage, which in turn causes the entire crane to fail to work normally; thus, it brings huge losses to customers and causes great waste. It is not conducive to enhancing the competitiveness of enterprise products. It can be seen that the jib is the main bearing part of the crane, and its strength and dead weight are directly related to the safety and performance of the crane. In order to make the fatigue life of the boom meet the design requirements, high-strength materials are usually used to strengthen the strength of the boom, which will undoubtedly increase the weight of the boom and the whole machine, ...

AI Technical Summary

Problems solved by technology

In order to make the fatigue life of the boom meet the design requirements, high-strength materials are usually used to strengthen the strength of the boom, which will undoubtedly increase the weight of the boom and the whole machine, which will not help improve product performance, but will greatly increase manufacturing costs

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