Construction method of rapid dismantling and replacement of large tonnage marine propellers

Abstract

The invention discloses a construction method for fast dismantling and replacement of a large-tonnage marine propeller. The new and old propellers are placed on the general steel bracket and prop hub supporting seat respectively, and the new and old propellers are carried by a flatbed truck to realize Safe and fast transposition and movement of large propellers, lifting old propellers out of dock, new propellers after smearing red lead, shifting on pack, pressing into place and loosening, longitudinal shifting away from stern shaft, flatbed pallet retracting Lift the platform, carry the propeller horizontally to the scraping operation place on the side of the ship, check and scrape the contact high point of the inner cone hole surface of the propeller hub, etc., and complete the renewal of the large propeller after the contact and cooperation of the inner cone hole surface meet the technical requirements Work. Compared with the prior art, the present invention has the characteristics of stable and reliable assembly quality, time-saving and labor-saving, high operating efficiency, short construction period, low cost, and few potential safety hazards.

Description

technical field [0001] The invention relates to a construction method for replacing a marine propeller, in particular to a construction method for quickly dismantling and replacing a large-tonnage marine propeller, and belongs to the field of ship maintenance engineering. Background technique [0002] In the prior art, the replacement operation of large-tonnage marine propellers (about 100 tons in weight) is mainly carried out by means of several high-power pneumatic hoists. The specific construction method is as follows: [0003] Removal of the old propeller: First, on the hull plate above the propeller, several heavy-duty lifting lugs are symmetrically welded on the left and right sides (in special cases, before the welding of the lifting lugs, it is also necessary to weld the hull at the position corresponding to the welding heavy-duty lifting lugs). In the internal structure area, take structural reinforcement measures in advance); [0004] Then, carry out non-destruct...

AI Technical Summary

Problems solved by technology

[0009] It is not difficult to imagine that when a propeller with a weight of about 100 tons is lifted by a pneumatic hoist, it is time-consuming and laborious to find, locate and adjust the direction, and the operation is very difficult

[0010] This also directly leads to a substantial increase in the time and frequency of research and assembly between the propeller hub and the stern shaft in the process of propeller development and press-fitting; moreover, since the propeller is always in an unstable shaking state, it is extremely difficult to avoid the Problems such as bump damage, which may further increase the number of scraping and grinding, reduce installation efficiency, and increase the difficulty of installation operations

[0011] The most critical thing is that this may result in a reduction in the assembly quality of the propeller, and the ideal assembly quality cannot be achieved

[0012] In a word, the construction method for the replacement of large tonnage marine propellers in the prior art is time-consuming and laborious, and the installation period is long (because it takes about seven hours to complete a scraping and grinding operation, and it can only scrape and grind for two hours if you work more than ten hours a day. times, complete all the scraping and research work, and it will take at least three days until the assembly is completed), the operation efficiency is low, and the assembly quality cannot be guaranteed

[0013] In addition, in the construction method of replacing the propeller of a large-tonnage ship in the prior art, the propeller moves back and forth multiple times in the air under the lifting state of the air hoist, which is prone to safety accidents such as personal injury. In actual production operations, There have even been safety accidents such as propellers falling to the bottom of the dock

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