Laser Repair Technology (LRT)
Repair (LRT) |
Cladding (LCT) |
Freeform Manufacturing (LFMT)
When operating any type of mechanical equipment with moving parts,
repairing or rebuilding worn metal components is part of everyday life.
Repairing worn components typically saves dollars over purchasing new
When a worn part is rebuilt, the potential also exists to repair that component in
such a manner that it will have a longer wear life than a new part.
Repair Parts That Were Previously Un-repairable
The concept of repairing parts versus replacing them is not new; however,
the use of the Laser Repair Technology (LRT) to repair components previously
considered un-repairable is. Laser Deposition Technology (LDT) has a number of
key benefits over other repair techniques that make it possible to repair some
parts that were previously un-repairable. Using
other techniques, either the part could not physically be repaired, or it
was not economically feasible to perform the repair.
Some of the benefits of LDT over other repair techniques are:
- Metallurgical Bond versus Mechanical Bond
The LDT process creates a metallurgical bond which is much stronger than
the mechanical bond created using spray welding or plating techniques.
- Low, Controlled Heat Input
The LDT process creates very low and controllable heat input
with minimal dilution and heat effect zones.
- Minimal Stress and Distortion Created by Deposits
- Rapid Cooling Rates
- Cost Effective for Repairs and Manufacturing
The key benefits of LDT over other techniques are that it 1) creates a stonger
bond and 2) inputs less heat to the part being repaired.
The benefits of the stronger bond are obvious. The lower heat input
means less distortion of the part during the repair process. These
two benefits make the LDT process unique.
Following are a number of specific case studies where the benefits of Laser
Repair Technology (LRT) made it possible to repair parts that were previously
Contact Us about the details of your project.
Case Study: Titanium Bearing Housing
An application employing a low-wattage repair is shown in
figures below. This is a
Ti-6Al-4V bearing housing from a gas turbine engine. The bearing seating area was
worn to an out-of-tolerance condition, and the housing was considered scrap. The
process was utilized to build up the worn area, which was followed by final machining
to print tolerances. This housing was successfully repaired, with no measurable
distortion, and has completed an evaluation run in a test engine. The repair costs
are about 50% of new pricing plus it saves all of the materials that would be
required to manufacture a new housing. Delivery for the repaired housing is a few
days compared to several weeks for a new housing.
Bearing Housing Before Repair
Bearing Housing After Deposition
Case Study: Inconel 718® Compressor Seal
below illustrate a very finesse repair of a gas turbine Inconel® 718
compressor seal. When the labyrinth seal diameter wears 0.008 in., the engine
loses power and the seal is considered scrap. This test seal was repaired using
Compressor Seal Before Repair
Compressor Seal After Laser Deposition
Compressor Seal After Final Machining
Case Study: Low-wattage Repair of Titanium Components
Low-wattage repair of titanium components
has many potential aerospace,
Department of Defense, and commercial applications.
The figures below show a typical low-wattage repair
of a simulated defect in this Ti-6Al-4V plate. Multiple layers
were applied to achieve the full depth of deposit required for this
repair. Note the typical columnar grain growth in the deposit and the very
small HAZ in the surrounding base material. Minimal distortion was experienced
with this type of repair, which may be used on several aircraft structural
components such as wing spars or bulk heads. Several gas turbine engine
components as well as land-based turbine blades are potential candidates for
this low-wattage repair. Repairs of this type typically involve critical
components and require substantial qualifications of the repair process
before the process can be implemented. The potential savings in time, materials,
and dollars is great.
Laser Deposition Samples
Case Study: Repair of Ti-6Al-4V Forging
RPM Innovations received a Ti-6Al-4V drive plate forging that needed repair.
The forging was undersized. Material needed to be
added to the part to build it up so it could be machined to the proper fit.
The drive plate is for an atomizer wheel used in a
Flue Gas Desulfurization system.
All of the parts in the atomizer wheel rotate up to 15,000 RPM. For this system, it is
important that the part be precisely machined and that the material used
be resistant to wear. Titanium is used to minimize the weight of the part
while maintaining the hardness and strength needed for the application.
Using Laser Repair Technology (LRT), material was added to the part. Once
the material was added, the strong metallurgical bond allowed the material
to be machined off to the proper fit while maintaining the required strength
and hardness for the application. The low heat input of
the LRT process ensured that the part did not change its shape or
Forging As Received
Ti-6Al-4V atomizer drive plate.
Part rotates up to 15,000 rpm.
Forgings were undersized.
Used Laser Repair Technology (LRT) for building up material.
Forging During Deposition
Forging After Deposit
Forging After Final Machining
Case Study: Pick-up Tube Repair
A "Pick-up Tube" rotates in a circular path and is used to pick up a slurry mixture.
The majority of wear on this part occurs on its outer edge. The outer edge was
originally manufactured using an alloy Inconel 718. Conventional methods to repair
this part were
tried; they all failed.
RPM Innovations developed a repair process using Laser Repair Technology (LRT),
Inconel 718 as the base filler material, and Nickel-Chrome-Boron as the final
surface material. The repaired Pick-up Tube has improved wear, abrasion
resistance, and a longer service life.
rotates in a circular path and picks up a slurry mixture.
Wear occurs on the outer edge of the part,
which is made out of the alloy Inconel 718.
Conventional repair methods had failed.
Repaired using Laser Repair Technology (LRT), Inconel 718 as the base filler material,
and Nickel–Chrome–Boron deposited as the final surface material.
Repaired part has
improved wear, abrasion resistance, and a longer service life.
Pick-Up Tube Before Deposit with an Inconel 718 Plug in Place
Pick-Up Tube After Laser Deposit
Pick-Up Tube Post Machining
Case Study: Stator Housing Repair
A Stator Housing came into our shop for repair. Three of the ribs on the housing
were worn over 0.100". Each of the three ribs were positioned on the part at a
different angle, which the repair process had to take into account.
RPM Innovations developed a repair process using Laser Repair Technology (LRT)
and 420 Stainless Steel. Previous attempts were made to repair this part
using conventional repair methods. These previous attempts failed due to the
distortion created with the introduction of high heat input.
Stator Housing As Received
Stator Housing had three separate ribs that had worn out over 0.100”.
Each rib was at a different angle that had to be accounted for.
Parts were repaired using laser deposition with 420 Stainless Steel.
Part was previously repaired using conventional welding methods.
These methods caused too much distortion due to the heat input.
Before Laser Deposition
During Laser Deposition
After Laser Deposition