UPTOWER SOLUTIONS

Yaw Ring Repair

Using precision machining, the yaw ring is repaired on-site, leading to significant savings and reduced Co2 output, compared with replacement costs. Our patented system removes the need for the yaw ring to be replaced, eliminating the expensive, time-consuming and potentially detrimental disassembly of the rotor and nacelle.

Operated by our trained technicians, the patented CNC machine applies the proprietary repair method, working at extremely fine tolerances, to remove and reinsert machined yaw ring teeth precisely. Because the repairs take place inside the wind turbine tower/nacelle, our method is less dependent on weather, potentially reducing downtime.

The yaw ring repairs eliminate the costly, time-consuming and potentially detrimental disassembly of the rotor and nacelle – a requirement when replacing the entire yaw ring gear.

REDUCED DOWNTIME

We conduct on-site repairs, provide tailored solutions, and respond quickly to minimize downtime for your wind turbines. With minimal downtime, the turbine’s performance is restored immediately.

RESSOURCES

With no need for new components and cranes, we are able to minimize carbon footprint, manpower and logistics compared to yaw ring removal.

TOTAL ECONOMY

We can enhance the project’s total economy by promptly deploying and offering efficient solutions without the need for external cranes. Furthermore, our yaw ring repair minimizes costs as the yaw ring is repaired, not replaced.

DURABLE RESULTS

Onsite uptower repairs offering precise and durable results.

CONTACT US

Our team of experienced professionals will guide and advice you towards the
best possible solution that takes time, economy and durability into consideration.

Hans Løvlund Toft

CTO

+45 53 57 00 43 | hlt@cnconsite.dk

Process

From challenge to solution

Commissioning

Planning

Implementation

Handover

Followup

Commissioning

The repair technician contacts the wind park within 24 hours to assess yaw ring damage and repair options for the CNC wind turbine, facilitating a quick repair process.

The wind park reports damage to the yaw ring and the wind turbine type to CNC Onsite.

Within 24 hours, our repair technician calls to discuss the damage.

Within the next working day, we will assess the damage and repair options. The quote is issued the same day.

Once the customer approves the plan with a purchasing order, the repair can begin within a matter of days.

Planning

CNC machine repairing a wind turbine component.

We plan the repairs in detail to carry out the job to exact specification and minimal disruption.

The yaw ring type and the number of damaged teeth determine the number of new, pre-manufactured replacement yaw ring segments.

The CNC machine is programmed to fit the exact wind turbine type.

The planning takes into account any unforeseen events, like other turbines affected.

Implementation

Technicians repairing wind turbine yaw ring teeth using a portable CNC machine

The technicians will start work at dawn, bringing the portable CNC machine and replacement yaw ring teeth.

The team transports the portable machine parts to the tower and will assemble it in the nacelle.

Under supervision, the preprogrammed milling machine is mounted to the yaw ring and will work to excise the damaged segments, leaving precisely measured pockets.

Our technicians insert the new segments fixes them mechanically and robustly.

Upon completion, the wind turbine is tested.

Handover

When the repairs are complete, our technician discusses the final result with the customer and the turbine will be started up.

The repair job is signed off by the customer and our technicians completes the job by issuing a repair report to the customer

Followup

As part of our high quality standards and professional approach, we follow up on each job.

Each case is individual and the experience accrued is documented for future jobs.

We trace each repair job and follow up with the client to ensure continued satisfaction and longevity of the repairs.

SERVICE FOR ON- AND OFFSHORE WIND TURBINES

„We can now offer a repair service for both onshore and offshore at a fraction of the cost of replacing the entire yaw ring, and that makes it viable to keep perfectly good wind turbines operating for longer. We’re eliminating the need for manufacturing a new yaw ring and above all the huge logistical effort required to transport a yaw ring to the site, deploy cranes, which is particularly tricky offshore, and replace it‟

Søren Kellenberger, Sales Director

YAW RING REPAIR

Learn more about Wind Turbine yaw ring repair from the fold-out menu.

Can a yaw ring be repaired on a wind turbine? A wind turbine yaw ring that has suffered damaged teeth can be repaired. The repair can be done by competent technicians equipped with the right precision machine. The repairs are done directly in the wind turbine tower/nacelle. The whole yaw ring does not need to be replaced. This naturally saves significant costs. Removing the whole yaw ring and installing a new yaw ring means the whole nacelle must be removed first. This involves a crane and other logistics as well as lost production during downtime.

How is the yaw ring repaired? The repairs of the yaw teeth are performed uptower without the need to disassemble any wind turbine parts. The Danish company, CNC Onsite, has developed a precision machine and a method - both of which are patented - that technicians employ to repair yaw ring teeth in a range of wind turbine types. How is the yaw ring repaired? The wind turbine yaw ring is located below the nacelle. The space around the yaw ring itself can sometimes be tight. CNC Onsite’s precision machine is designed to fit into the limited space available. The process for yaw ring repair is simple. The precision machine is programmed by the technician and then mills away the damaged yaw teeth automatically. This leaves a pocket which has grooves, ridges and threaded holes that are used to hold the new replacement teeth firmly in place. The new pre-fabricated teeth come in segments which have from 1 tooth to 6 teeth depending on the damage and the turbine type. The new yaw ring teeth, which have been designed to fit the damaged yaw ring exactly, are then inserted into the pocket. The new segment is mechanically fixed in place and slots in like a jigsaw piece thanks to the matching pattern on both the new segment and inside the pocket.

How many yaw ring teeth can be repaired? It is possible to do consecutive repairs and in principle all teeth on a yaw ring can be replaced by this method

How many wind turbines are affected by damaged yaw ring teeth? There are no exact numbers but it is estimated that 5-10% of all turbines will experience damages to the yaw ring to some degree during its lifetime. These 5-10% are not evenly distributed across the fleet. It is more often seen that some sites are more exposed to this type of damage due to site conditions. These parks will often have a higher percentage of affected turbines, while other will have lower percentages or none at all. However, usually if one yaw ring has damage, more than one wind turbine will suffer from the same type of yaw ring damage within that site. CNC Onsite therefore recommends that all wind turbines are checked for yaw ring damage before the repair team arrives to repair the wind turbine yaw rings.

How quickly can the yaw ring technicians come to the wind farm/park? CNC Onsite’s yaw ring repair technicians can be onsite in a matter of days from received purchase order depending on where in the world the yaw ring repairs need to be conducted. The service is offered worldwide. How long it takes to repair the yaw ring depends on how many teeth are damaged and other factors like accessibility to the wind turbine. The CNC machine is hoisted up in the nacelle in several parts and is then assembled in the small space around the yaw ring. The average time for yaw ring repair is between 8 and 12 hours per segment.

What does it cost to repair a yaw ring? Compared to the alternative which is to replace the whole yaw ring when the teeth are damaged, the yaw ring repairs conducted by CNC Onsite’s team will cost a fraction of the replacement of the whole ring. This is because the whole yaw ring replacement involves a crane to lift off the nacelle, more manpower and safety precautions, which are all costly but also the wind turbine downtime is costly. Each case has a different cost calculation. No case is exactly the same when it comes to damaged yaw ring.