Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Electric power generator, steam turbine rotor spindle repaired by laser and repairing method thereof

A steam turbine rotor, laser repair technology, applied in the direction of laser welding equipment, machines/engines, liquid fuel engines, etc., can solve the problems of reduced service life, low surface hardness, etc., achieve high creep limit, good wettability, and good durability The effect of intensity

Inactive Publication Date: 2009-06-24
SHENYANG DALU LASER TECH
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Generally, copper plating is used for brush plating, which has good bonding strength, but the surface hardness is low, and the worn parts continue to wear after brush plating, so the service life is reduced

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0027] Example 1 Medium and low pressure rotor shaft of 200MW steam turbine

[0028] The weight of the rotor is about 20 tons, the length is 6m, the maximum rotation diameter (last stage blade) is 2.4m, the material of the rotor shaft is 25Cr2Ni4MoV, the diameter of the main journal is φ300mm, the damage width is 250mm, and the maximum damage depth is more than 1mm. The fatigue layer is removed by machining; the alloy powder with the weight percentage content of Cr20, Mo4, W3.5 and the balance of Ni and the alloy powder with the weight percentage of Cr20, W4, C0.5 and the balance of Co are laser cladding respectively. The process parameters of repairing and laser cladding are: laser power 1500W, spot diameter φ4mm, spot moving speed 10mm / s; reshape by machining, and pass the acceptance test. After various tests, its hardness index has reached the HB240-260 required by the original shaft hardness, and there are no holes, slag inclusions, cracks and other defects in the non-dest...

Embodiment 2

[0029] Example 2 300MW Generator Rotor Shaft

[0030] The weight of the rotor is about 40 tons, the length is 7m, the material of the rotor shaft is 30CrNiMo, the diameter of the main journal is φ450mm, the damage width is 80mm, and the maximum damage depth is more than 1mm. The fatigue layer is removed by machining; the alloy powder with the weight percentage content of Cr 20, Mo 4, W 5, Al 0.8, C 0.2, and the balance of Ni and the weight percentage of Cr 20, W 4, C 0.1, Nd 0.3 The alloy powder with the remaining Co is repaired together with laser cladding. The process parameters of laser cladding are: laser power 1800W, spot diameter φ4mm, spot moving speed 5mm / s; and then machining and reshaping. Passed the acceptance. After various tests, its hardness index has reached the HB260-280 required by the original shaft hardness, and there are no holes, slag inclusions, cracks and other defects in the non-destructive testing. According to the results of metallographic analysis,...

Embodiment 3

[0031] Example 3 50MW Generator Rotor Shaft

[0032] The weight of the rotor is 26 tons, the length is 6m, the material of the rotor shaft is 34Cr2Ni4MoV, the diameter of the air seal journal is φ420mm, the damage width is 50mm, and the maximum damage depth is 0.8mm. The fatigue layer is removed by machining; the alloy powder with the weight percentage of Cr25, Mo4, W5, B0.5 and the balance of Ni and the weight percentage of Cr25, W4, C0.2, N0.1 and the balance of Co are used Alloy powder is repaired by laser cladding together, and the process parameters of laser cladding are: laser power 1200W, spot diameter φ4mm, spot moving speed 8mm / s; and then machining and reshaping. Passed the acceptance. After testing, its hardness index reaches the HB260-300 required by the original shaft hardness, and there are no holes, slag inclusions, cracks and other defects in the non-destructive testing. According to the results of metallographic analysis, the structure of the cladding layer ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
thicknessaaaaaaaaaa
Login to View More

Abstract

The invention provides a laser-repaired generator and steam turbine rotor shaft, the surface of the base body is formed with an alloy cladding layer that is fused with each other and has a composition completely different from the base body; 0.1mm; the alloy coating is nickel-based, cobalt-based or iron-based alloy. The present invention also provides a laser repair method for the generator and steam turbine rotor shaft, which adopts the preset laser cladding method, and its process parameters are: laser power 1200-2000W; spot diameter φ4mm; spot moving speed 5-16mm / s. The advantages of the laser repaired generator, steam turbine rotor shaft and repair method thereof provided by the present invention are: the bonding strength between the substrate and the laser melting layer is not lower than 90% of the original substrate; the melting layer and its interface structure are dense, and the grain Small, without holes, slag inclusions, cracks and other defects; the surface of the repair layer has a high creep limit, good durable strength and good thermal fatigue and fracture resistance.

Description

Technical field: [0001] The invention relates to a generator, a steam turbine rotor shaft and a repair method thereof. Background technique: [0002] The rotor shafts of steam turbines and generators are large in size and weight, high in precision level, complex in manufacturing process, high in production cost and long in cycle. And once there is a problem in operation, its impact is huge. Therefore, the design of this type of rotor is an infinite life design, that is, it can be used continuously for more than 20 years under normal process conditions. [0003] The general manufacturing process of the rotor shaft includes whole forging type, sleeve type, combined type and welding type. Regardless of the structural form, its quality requirements are relatively high. Due to working at high temperature and high speed, the material is required to have a high creep limit, good durable strength and good thermal fatigue and fracture resistance. The larger the capacity of the uni...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): H02K1/28B23K26/00F04D29/04
Inventor 陈江王一兵张静波
Owner SHENYANG DALU LASER TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products