Laser cladding combats corrosion

Laser cladding combats corrosion in the oil and gas industry

Corrosion is a massive problem across all industries. NACE (National Association of Corrosion Engineers) estimates the global cost of corrosion at $2.5 trillion a year.  The oil and gas industry represents a big chunk of these costs with its complex and challenging production techniques and the environmental risks should components fail.

From offshore to downhole drilling and production, corrosion strikes virtually every component across the oil and gas industry. While there are many sources of corrosion, there are also many methods to prevent or slow the process and protect expensive components.  Laser cladding is increasingly being used as a solution for many corrosion problems in the industry.


Laser cladding
, also known as laser metal deposition (LMD), is a process that uses metal alloy powders to apply a protective coating to the surfaces of metal components to increase their corrosion or wear-resistance.  Laser cladding offers a number of advantages over more traditional additive processes, including:

  • Improved metallurgy with higher material hardness
  • Lower powder costs due to thinner coatings
  • Less stress due to lower heat input
  • Shorter process time than traditional processes like PTA

 Here are a few examples of how LMD is being used in the oil and gas industry:

In offshore drilling, hydraulic cylinders are exposed to salt from ocean spray that causes corrosion, pitting and scratching.  This can lead to oil contamination, seal failure and eventually machine failure.  Laser cladding a piston rod provides a durable coating with extreme hardness that can withstand harsh environmental conditions.
 
Another potential application in the offshore industry are risers in offshore structures. The splash zone area above the high tide mark experiences severe corrosion. Any protective coating or film is constantly eroded by waves.  However, LMD provides a metallurgically bonded corrosion-resistant coating that can be field repaired.
   
Downhole drilling tools are another type of equipment that can benefit from the cladding process. Drill stabilizers are exposed to extreme wear from rubbing against the wall of the hole. In harsh conditions, long hole drilling operators often need to change worn stabilizers, incurring downtime and labor costs.  LMD provides a high wear-resistant coating with a metallurgical bond.
 
Drillpipes experience extremely harsh conditions such as formation fluids, drilling mud, stress corrosion and erosion.  Drillpipe leaks or washouts occur in the threaded drillpipe connections called tool joints.  Internal diameter cladding, which applies a coating on the internal surfaces of tubes and pipes, provides a highly corrosion- and wear-resistant coating.
 

There are other oil and gas applications that can benefit from this process. If you have questions about applications not mentioned here, get in touch with our experts or leave a comment in the space below. 

Our e-book on laser cladding solutions for corrosion offers additional examples of applications in several other industries. Download it here.

Extend mining equipment

Control corrosion, extend mining equipment life with laser cladding

Like most industries, the mining industry faces significant costs from corrosion.  One study conducted in Chinaestimated that direct corrosion costs in coal mining were 84.70 billion RMB ($13.4 billion), representing 4.67% of the total annual production value of coal. 

While wear and mechanical damage are major causes of costs and downtime in the mining industry, corrosion is also a considerable problem that can shorten equipment life and cause unplanned downtime.  Laser cladding, also known as laser metal deposition (LMD), can be a viable and cost-effective solution for the mining industry.

In laser cladding, a stream of metallic powder is fed into a laser beam to apply a protective coating to the surfaces of metal components to increase their corrosion or wear-resistance. This process offers a number of advantages over traditional additive processes, including:

  • Improved metallurgy with higher material hardness
  • Lower powder costs due to thinner coatings
  • Less stress due to lower heat input
  • Shorter process time than traditional processes like PTA

Here are some examples of how laser cladding is being used in to extend equipment life in the mining industry:

Smelters: Smelters are exposed to highly abrasive and corrosive environments, and maintenance downtime is very costly.  LMD applies a protective coating to the smelter’s cooling elements, as well as to the boiler tubes in the waste heat boiler at the smelter.  Results include improved operating efficiency and longer time between maintenance shutdowns.

Mining Boom Cylinder:  Mining boom hydraulic rams are exposed to impact abrasion and corrosion, and internal bearing surfaces are subjected to wear from dust particle contamination. Applying LMD to these elements results in better than OEM surface metallurgy and longer equipment life.

Cutter Drums: Underground mining cutter drums are subjected to damage from particles and moisture. An effective solution is machining to clean up the drum surface, followed by laser cladding and remachining back to OEM specifications. This process extends drum service life and provides an alternative to replacing expensive equipment.

Remanufacturing: Cladding can rebuild and restore expensive mining equipment such as inner and outer cutter drums, gear teeth, journal areas of shafts, pug mill paddles, and bearing housings in gear cutter cases.

Maximizing equipment uptime and availability is critical in the mining industry. In addition to these examples, there are other mining applications that can benefit from LMD. If you have questions about applications not mentioned here, get in touch with our experts or leave a comment in the space below.

Want to know more about laser cladding solutions for corrosive environments? Our e-book offers additional examples for other industries including power generation and oil & gas. Download it here.

PowerGen corrosion solutions

Laser cladding – powerful wear and corrosion solutions for Power Generation

Harsh environments are a fact of life in the power generation industry.  Equipment is subjected to all kinds of abuse, from high temperatures and high pressure to fuel that is highly corrosive and erosive.

Laser cladding, also known as laser metal deposition (LMD), can solve many of these challenges by providing a highly corrosion- and erosion-resistant coating that extends the life of expensive components.  Compared to traditional additive processes, LMD provides a strong metallurgical bond with higher material hardness, less stress due to lower heat input, and lower powder costs due to thinner coatings.

Here are just a few examples of how this process can extend equipment life and prevent unplanned downtime in the power generation industry:

Superheater tubes:  Laser cladding can significantly reduce corrosion in boiler tubes. Boilers at waste to energy facilities are subjected to temperatures of 1,600° – 2,000° F and pressures from 850 – 1200 psig.  Typical superheater lifespan with Inconel 625 overlays is 16-24 months, after which the entire primary and secondary superheater is usually replaced at significant cost.
 
By cladding a highly corrosive and erosive resistant coating onto the superheater tubes and platens, we have increased their lifespan from 16-24 months to 6 years.
 
Soot blowers: Soot blower lances are exposed to the same harsh environments as superheater tubes, resulting in downtime and high maintenance costs.
 
Laser cladding the lances has extended their lifespan up to 6 times, reduced replacement costs, and significantly reduced maintenance time.
 
Valve applications: Valve balls and seats, and valve housing and casings are also exposed to extreme conditions in power generation plants.  LMD can mitigate wear and/or corrosion using a typical coating thickness of 0.025” to 0.050” and can achieve a coating hardness up to 70 HRC within 0.005”-0.008” of the base material.
 
Pump applications:  Pumps are another critical component at power plants that are subjected to wear. In a centrifugal pump, wear of the impeller or other pump components can be worsened by suspended solids. In many cases, a wear-resistant laser clad coating can be applied to extend the component lifespan, or original material can be applied to the wear location to allow for component restoration.
 
In a twin rotary screw pump, the top flight of a screw is exposed to metal-to-metal rubbing contact with the casing or adjacent shaft screw, causing wear.  To prevent wear, a laser hardfacing coating forms a metallurgical bond rather than a mechanical bond commonly found in thermal spray processes or spray and fuse applications.  LMD also prevents wear to pump shafts and shaft components.

Many other components in power generation plants can benefit from laser cladding. If you have questions about equipment not mentioned here, get in touch our experts or leave a comment in the space below.

Our e-book on laser cladding solutions for corrosion offers additional examples of applications in several other industries. Download it here.

LMD for embedding components

Using laser metal deposition for embedding components

The need for process monitoring or temperature control of components has become an increasing challenge as numerous industries push their technological boundaries. Examples of these components include thermocouples, accelerometers, heating coils and cooling channels.

Laser Metal Deposition (LMD) is showing significant promise in exploring and testing some of these possibilities.  Welding processes are currently being developed that enable thin-walled components to be fully welded (encased) into the process tooling.  Embedded components with a wall thickness as little as 0.006” (0.15 mm) have been successfully welded directly into the body of functional tools.  Powder filler metal is then laser welded in sequential layers to bring the pre-machined region to a “positive” condition in order to facilitate final machining.

Subsequent post-weld machining to dimension of the tool body results in the embedded components being completely concealed within the body of the tool, with the exception of needed input/output hardware connections.

Some application examples include:

  • Aerospace welding used to seal high-temperature heating elements into aircraft monitoring equipment to prevent freezing, yet allowing the body of the device to be machined to an aerodynamic profile.
  • Thin walled (0.050” diameter) tubing has been embedded directly into the cavity face of molds to facilitate faster cooling.
  • Thermocouple devices embedded 0.010” – 0.020” below the surface they are monitoring.

Currently a number of industries are showing interest in this process, including aerospace, Department of Defense, chemical processing, power generation and injection molding.

If you’d like to learn more, ask one of our experts or leave a comment in the space below.

Extend boiler tube life

Extend boiler tube life with laser metal deposition

One of the harshest operating environments in the power generation industry is within the boilers at waste-to-energy (WTE) facilities.  Between high temperatures, high pressure, and fuel that is highly corrosive and erosive, WTE boiler components like superheater tubes and platens need to be replaced regularly – at a significant cost for the energy producer.

The conventional solution for minimizing erosion and corrosion on boiler components is to use an overlaying alloy of Inconel 625.  While Inconel can be effective, one of our customers found that it fell short of their desired component lifetime performance goals.  Their typical superheater lifespan was 16-24 months, at which point they were replacing the entire primary and secondary superheater at significant cost.

Working together, we developed a solution using the laser metal deposition (LMD) process along with a powdered alloy that improved both corrosion and wear-resistance. The result? Five years later, these tubes are still in operation.

In addition to extending the life expectancy of boiler tubes, the laser metal deposition process resulted in improved thermal efficiencies, reduced maintenance costs, and production costs per linear foot that were equal to or less than traditional Inconel 625 overlays.

These results have applications in other industries that burn harsh fuels, including the biomass and pulp & paper industries. To learn more about this project, download our case study or contact us to talk to an expert.