CN-116900225-B - Forging method of rudder bar

CN116900225BCN 116900225 BCN116900225 BCN 116900225BCN-116900225-B

Abstract

The invention discloses a forging method of a bent rudder stock, which belongs to the technical field of bent rudder stocks and comprises the steps of selecting a steel blank with a round or square section, preheating the steel blank, forging, namely cutting a shoulder by a lower chopper, drawing and bending, wherein the lower chopper adopts a slope to cut the shoulder by 200mm when the lower chopper cuts the shoulder, mounting the lower chopper on a square drawing machine for drawing and bending after the lower chopper cuts the shoulder, placing the bent rudder stock between a flat anvil and a V-shaped anvil for fixing by using a clamp and applying force by using a hammer head when the bent rudder stock is bent, carrying out size calibration on the bent rudder stock after the forging operation is completed, carrying out heat treatment on the bent rudder stock, carrying out quality inspection on the bent rudder stock after the heat treatment, carrying out surface treatment and spraying on the bent rudder stock after the quality inspection, and ensuring that the slope of the slope cuts the inclined surface of the bent rudder stock can lead to be more uniform in stress distribution and reduce the concentration of local stress, thereby improving the strength and fatigue resistance of the bent rudder stock of a ship.

Inventors

ZHOU CHAO
SHANG BINBIN
LIU YUNFENG
LIU JIANHUI

Assignees

山东宝鼎重工实业有限公司

Dates

Publication Date: 20260512
Application Date: 20230731

Claims (4)

1. A forging method of a rudder bar is characterized by comprising the following steps, Firstly, selecting a steel blank with a round or square section; Preheating the steel blank; The forging operation comprises the steps of cutting the shoulder by a lower chopper, drawing and bending, wherein the inclination is adopted for cutting the shoulder when the lower chopper cuts the shoulder, the lower chopper is arranged on a drawing machine for drawing after the lower chopper cuts the shoulder, the middle part of a bent rudder stock is aligned with a clamp of the drawing machine when the lower chopper is arranged on the drawing machine after the lower chopper cuts the shoulder, the bent rudder stock of a ship is taken down from the drawing machine and is arranged on a diagonal tip pressing machine after the drawing is completed, the diagonal tip pressing machine is started to deform diagonal tips at two ends of the bent rudder stock of the ship, the diagonal tip angles and lengths at two ends of the bent rudder stock are controlled by adjusting the strength and the position of the diagonal tip pressing machine, the bottom surface of the bent rudder stock is inclined towards the central line when the tip is pressed, so that the bias is reduced, the situation that the steering machine cannot rotate is avoided, and the bent rudder stock is placed between a flat anvil and a V-shaped anvil by using the clamp to fix the clamp and a hammer head is used when the bending is performed; Step four, after the forging operation is completed, carrying out size calibration on the bent rudder stock; step five, after the size calibration, carrying out heat treatment on the bent rudder stock; step six, after heat treatment, carrying out quality inspection on the bent rudder stock; step seven, after quality inspection, the surface of the bent rudder stock is treated and sprayed; In the third step, the bent rudder stock is pulled out and deformed through mechanical force or hydraulic force, the force and the speed of a square pulling machine are adjusted, the bent rudder stock is controlled to be pulled out and deformed, and when the length of a forge piece exceeds 6 meters, the pulling out is completed; in the seventh step, the forged and heat-treated bent rudder stock is subjected to surface treatment by cleaning the surface, cleaning the bent rudder stock surface by using a cleaning agent and a tool, removing dirt and oxide generated in the forging and heat treatment process, performing shot blasting treatment on the bent rudder stock surface by shot blasting equipment, and spraying an anti-corrosion coating.
2. The forging method of a bent rudder stock according to claim 1, wherein in the third step, the bending hammer head is bent gradually to a target shape by applying a force from one side of the bent rudder stock.
3. The forging method of a rudder trunk according to claim 2, wherein the hammer head force is perpendicular to the axial direction of the rudder trunk.
4. The method of forging a bent rudder stock according to claim 1, wherein in step six, the forged bent rudder stock is subjected to quality inspection including dimension detection, nondestructive detection, and chemical composition analysis.

Description

Forging method of rudder bar Technical Field The invention belongs to the technical field of rudder bending poles, and particularly relates to a forging method of a rudder bending pole. Background The rudder bar is a key component on the ship and is used for controlling steering of rudder pieces and operation of steering engines. The bent rudder stock is a connecting rod-shaped member and is connected between the steering engine and the rudder blade to transfer force and torque generated by the steering engine so as to realize the steering and steering of the ship. The rudder bar is typically forged from high strength steel or other alloy materials to ensure that it has sufficient strength and rigidity to withstand the forces generated by the steering engine and hydrodynamic loads of the vessel during sailing. The shape and size of the rudder stock will vary depending on the size, type and operational requirements of the vessel. Generally, the rudder stock is cylindrical or flat rectangular in cross-section, having a length and diameter or width. The length of which is generally dependent on the rudder blade and the layout requirements of the vessel to ensure that the blade has a sufficient turning angle over the operating range, the diameter or width of the bent rudder bar being of a size dependent on the required strength and rigidity, and the load to be carried. The manufacturing process of the rudder stock generally includes forging, heat treating, and machining. Firstly, forging and forming selected steel materials through a forging process to improve the strength and the compactness of the material. Then, a heat treatment process, such as annealing or normalizing, is performed to relieve internal stresses and improve the mechanical properties of the material. Finally, machining is performed according to design requirements, including turning, milling, grinding and the like, to obtain the required geometric dimensions and surface accuracy, but the conventional rudder stock is mostly processed by adopting right-angle cutting shoulders, and the stress distribution is uneven. Disclosure of Invention The invention aims to provide a forging method of a rudder stock, which adopts right-angle shoulder cutting and has the problem of uneven stress distribution. In order to solve the existing problems, the invention provides a forging method of a rudder stock, which comprises the following steps, Firstly, selecting a steel blank with a round or square section; Preheating the steel blank; Step three, forging operation, which comprises cutting the shoulder by a lower chopper, drawing and bending, wherein the inclination is adopted to cut the shoulder by 200mm when the lower chopper cuts the shoulder, the lower chopper is arranged on a square drawing machine for drawing after the shoulder cutting treatment, and the bent rudder stock is placed between a flat anvil and a V-shaped anvil and fixed by a clamp when bending and force is applied by a hammer; Step four, after the forging operation is completed, carrying out size calibration on the bent rudder stock; step five, after the size calibration, carrying out heat treatment on the bent rudder stock; step six, after heat treatment, carrying out quality inspection on the bent rudder stock; And seventhly, after quality inspection, the surface of the bent rudder stock is treated and sprayed, the inclined plane of the inclined cutting shoulder can enable the stress distribution to be more uniform, and the concentration of local stress is reduced, so that the strength and fatigue resistance of the ship bent rudder stock are improved, and the inclined cutting shoulder can reduce the material loss in the cutting process. As a further improvement of the technical scheme, the bending rudder stock is subjected to drawing deformation through mechanical force or hydraulic force, the force and the speed of a square drawing machine are adjusted, the drawing deformation of the bending rudder stock is controlled, and when the length of a forging exceeds 6 meters, drawing is completed. The technical scheme is further improved, the ship rudder bending pole is taken down from the square pulling machine and is arranged on the inclined pin pressing machine, the inclined pin pressing machine is started to enable inclined pins at two ends of the ship rudder bending pole to deform, and the angle and the length of the inclined pins at two ends of the rudder bending pole are controlled by adjusting the strength and the position of the inclined pin pressing machine. As a further improvement of the technical scheme, the bottom surface of the rudder stock is inclined towards the central line during tip pressing, adverse factors caused by unbalance weight are reduced to the greatest extent, and the rudder stock is smoothly pulled to the technological length of the forge piece. As a further improvement of the above solution, in step three, the bending hammer head applies a force starting from the