m

LORD Corporation

With more than 3,100 employees in 26 countries, 19 manufacturing facilities and 10 R&D centers worldwide, we're there for our customers.

Our Company
Learn about Parker’s safety-focused approach to COVID-19. Read More

What You Need to Know About the Next-Generation MWD Shock Absorber

( 02/21/2018 ) Written by: Adam Keithly, P.E.

LORD® Axial Isolators are specifically designed to protect Measurement While Drilling (MWD) electronics from axial shock and vibration. Although we have developed and supplied this technology to the directional drilling market for many years, recent advancements have enhanced the tool’s reliability. Below are some key facts you need to know when considering this solution.

 

 

Has the Generation 3 axial isolator been thoroughly tested? Yes. Since this next-generation MWD shock absorber was introduced in late 2015, several hundred tools have been deployed across all major North American oil basins.

How effective is the MWD shock reduction tool (SRT)? The field-proven Generation 3 Axial Isolator extends the life of our customers’ MWD tools and protects downhole electronics in a broad range of operating conditions by significantly reducing the magnitude and quantity of shock events. Our MWD isolation and shock mitigation devices have field-proven, anti-rotation and sealing features, and LORD customers regularly report more than an 80% reduction in axial shock events over 30 g’s.

How are LORD Generation 3 Isolators different from earlier generations? In the early generations, we achieved the target dynamic performance to protect tools from shock and vibe, but we found the elastomer elements needed to be re-designed to increase longevity, broaden the operating envelope to allow one tool to fit most users, and allow for more cost-effective replacements. We were able to achieve these goals with the current Gen 3 tools. 

How reliable is this shock damper? These axial isolators use replaceable non-linear elastomer spring/damper elements. This improves reliability and shortens maintenance cycles versus alternatives that employ conventional metal springs with hydraulic compensation. Some customers that run our tools report that they last over two years in operation with regular maintenance.

Will it put my system into resonance? The beauty of the non-linear response of our proprietary shock reduction tool is that it cannot remain in resonance. If the system passes through resonance, the displacement increases, changing the stiffness and thereby shifting the point at which resonance occurs. The tool is effectively an auto "de-tuner."

Do I need an isolator? Isn’t it better to just lock everything down to get 1-to-1 transmissibility? Rigid assemblies not only directly transmit the high-G shock inputs coming from the bottom hole assembly (BHA), but they also amplify shock loads at different points along the MWD string. We have proven in lab tests and confirmed via downhole data that providing compliance in the system with an isolator significantly protects the electronics, with as much as 80% reduction in shock levels. That said, LORD does recommend using a muleshoe locking system as the Axial Isolator is dual acting, damping both the original compressive shock loads as well as the rebound shock loads.

Will it make my MWD string longer? Will it require a pony collar?  Yes, by integrating our shock damper into your pulser, the overall length of the MWD is increased approximately 36" (3 feet).  Proper length accommodations should be made to allow for the additional length in the MWD relative to the Non-Magnetic Drill Collar (NMDC).

How do I know how much life is left in the tool?  The remaining life of the elastomer kit in the tool is easily field-measurable. The shoulder-to-shoulder length of the tool starts at 35 ¼". The tool should be pulled for full service when it reaches 34 ¼" (1" of compression-set). Its relative length can be used to judge the remaining life (e.g., if it measures 35", with ¼" of set, the elastomer has 75% life remaining). For optimal performance, we advise servicing the tool between jobs. The elastomer package can be reinstalled during maintenance if it is still within the length tolerance.

How long does a typical service take? Approximately 30 minutes. Furthermore, since all required repair and maintenance (R&M) involves simple mechanical assembly, all service can be performed by entry-level technicians.

Is an oil-fill station required? No, the MWD shock absorber is not fluid-compensated so there is no need to purchase and maintain an oil-fill station to service the LORD Axial Isolator.

What does it cost to operate? These axial isolators have a low operating cost. A basic service, replacing seals and wear components costs less than $300. The tool is modular, and all components are available individually to minimize R&M costs.

Are they available to purchase or to lease? Purchase and monthly rental options are available. Leased tools are serviced in the LORD Houston office. Service kits are stocked in Houston as well. 

Where am I able to get additional information? To learn more about our axial isolator, watch the video, visit our webpage, or email us at OilandGas@lord.com.

 

 

ABOUT THE AUTHOR MORE BY THIS AUTHOR
Adam Keithly, P.E.

Adam Keithly is a Field Engineer at LORD Corporation. He is responsible for defining design specifications, coordinating field trials and developing solutions for shock, vibration and motion control.

Connect with me:

Contact Us