Views:21 Author:Juno Publish Time: 2020-12-25 Origin:Site
Mechanical equipment is prone to corrosion and wear of parts due to long-term working in harsh environments. Typical vulnerable components include impeller, large rotor journal, wheel disc, bushing, bearing bush, etc. Many of them are expensive, and with complex shapes. When these parts receive environmental erosion, they usually need to be strengthened or repaired.
When laser cladding machine is used for repair, the size of the journal can be restored without preheating the workpiece. And it does not produce metallurgical cracks, and the hardness can reach above HRC60.
The following we will introduce the laser cladding and repair process of shaft parts and turbine disks.
Laser cladding and repairing process of shaft parts
(1) Pretreatment process: including degreasing and rust removal on the surface of the workpiece → sandblasting → pre-cladding treatment (clean the area that needs laser cladding, and level the obvious defects);
(2) Quality inspection process: Use magnetic particle inspection, X-ray inspection, fluorescent inspection or display agent inspection to detect the cleaned surface to determine whether there are obvious defect areas;
(3) Laser cladding: laser cladding is carried out with alloy powder, no preheating, no metallurgical cracks, and high hardness can reach HRC63;
(4) Follow-up processing: including polishing and finishing and post-processing of laser cladding area; Wear-resistant coating is required if necessary;
(5) Quality inspection and acceptance: The inspection method is the same as step 2. After confirming that there are no defects on the surface of the part after laser cladding, the acceptance can be carried out. After the above processing steps, the shaft parts can be restored as new.
Laser Cladding and Repair of Turbine Disk
The key wearing parts of the hood are mainly the wheel disc and blades. To repair it, we generally use the laser cladding machine to flatten the obvious grooves on the turbine disk and the side wall, and weld all the holes and cracks on the wheel disk and the side wall. After that, the alloy powder with the performance of the base material is subjected to laser cladding treatment on the wheel. No need to lay the bottom layer or preheat, you can directly obtain the high hardness alloy layer.