Forging forming method of large piston rod forgings

The large piston rod forging is an important part of a certain type of ship with adjustable pitch propeller device, the material is 42CrMo steel, the middle is a large-flange, both ends are steps, the cross-sectional size changes are large. In the work by torsion, impact and other loads, high technical requirements. The manufacturing process of the piston rod is as follows: electric furnace smelting → vacuum refining → forging → heat treatment after forging → rough machining → ultrasonic testing (internal control) → quenching tempering → sampling and marking → testing → ultrasonic testing → * * * final processing → dimensional inspection → marking and delivery.

Gear precision forging: complete processing technology of gear precision forging

Gear precision forging is also a kind of precision forging, so compared with some ordinary gear forgings, the cost performance is higher, so we can only see the results of gear precision forging, but we can't see a production process. So now let's analyze the complete processing technology of gear precision forging.

How to determine the forging process plan and its importance

When forging and processing a forging, the first thing we need to do is to determine the forging process of the forging first, and know what process method to use to forge the forging in the next step. The forging process plays a very important role in the whole forging process, and it is also the premise to initially determine whether the forging can guarantee the quality. As long as the head is opened, the whole process can be better ensured, therefore, how important the scheme of the forging process is, let's first look at how the scheme of the forging process is determined.

Gear precision forging: complete processing technology of gear precision forging

Gear precision forging is also a kind of precision forging, so compared with some ordinary gear forgings, the cost performance is higher, so we can only see the results of gear precision forging, but we can't see a production process. So now let's analyze the complete processing technology of gear precision forging.

Different forging methods have different processes

Different forging methods have different processes, among which the process flow of hot die forging is long, and the general sequence is: forging blank blanking; Forging blank heating; Roll forging blank preparation; Die forging forming; Cutting edge; Punching; Correction; Intermediate inspection, inspection of the size and surface defects of forgings; Heat treatment of forgings for forging stress to improve metal cutting performance; Cleaning, mainly removing surface oxide scale; Correction; Inspection, general forgings to go through the appearance and hardness inspection, important forgings also through chemical composition analysis, mechanical properties, residual stress and other inspection and non-destructive testing.

Forging materials are mainly carbon and alloy steels of various compositions.

Forging materials are mainly carbon steel and alloy steel of various components, followed by aluminum, magnesium, copper, titanium and their alloys. The original state of the material is bar stock, ingot, metal powder and liquid metal. The ratio of the cross-sectional area of the metal before deformation to the cross-sectional area after deformation is called the forging ratio. The correct choice of forging ratio, reasonable heating temperature and holding time, reasonable initial forging temperature and final forging temperature, reasonable deformation and deformation speed have a great relationship to improve product quality and reduce costs.

Composition of forging cost

The composition of forging costs can be divided according to the economic use of production costs, and the cost items divided by economic use are called cost items. According to the regulations of the financial department, it is generally divided into six items: raw materials, fuel and power, wages and surcharges, waste losses, workshop expenses and enterprise philosophy fees. For forging production, the division and content of cost items are roughly as follows.

Analysis of Surface Cracking of Bearing Steel Forgings

The common cracks of bearing steel forgings are mainly divided into two categories: one is the cracks caused by the defects of raw materials, and the other is the cracking of forgings caused by improper forging process. Among them, the cracks caused by raw material defects mainly include raw material surface cracks, non-metallic slag, subcutaneous bubbles, white spots and shrink tube residues, etc., while the forging cracking caused by improper forging process mainly includes forging folding, forging overburning, forging wet cracking and forging tearing. Due to the different causes of the formation of cracks, there are some differences in the morphology and microstructure of the cracks, and the selected analysis methods and means are also different. Therefore, what kind of analysis idea should be taken for a certain case and what kind of analysis method should be selected in order to get the analysis conclusion quickly, accurately and economically, which is a common issue faced by the failure analysis work. 0350mm GCrl5SiMn electroslag steel forging materials produced by a company are used to forge bearing rings with a blanking length of 570mm. In the subsequent heating and forging process, it is found that the forging surface of the material is cracked along the axial direction, with a proportion of about 10%. Due to the large size of the forging, after annealing, two samples are cut out for inspection and analysis, with numbers of 1# and 2# respectively#.