Shaft Grounding Systems, Inc.
an early pioneer of this field
To our knowledge, Shaft Grounding Systems, Inc. is the only shaft grounding company that was born out of a real world need. In the mid 80s, the founder of Shaft Grounding System, Inc. not only identified a new class of bearing failure, but also out of necessity developed a long-term, maintainable fix for the problem.
Electrical discharge machining was discovered to be the root cause of electrically induced bearing failure. Simply out of sheer luck, SGSTM systems were developed in the pulp & paper industry and required the fix to be a permanent and reliable solution. The DNA of SGSTM products is directly attributed to being developed in an industry with extremely high performance standards.
Partnering with the field
A data farm center contacted us to discuss their ongoing continual electrical bearing failure despite having microfilament style shaft grounding devices installed. We have partnered with this company to receive their damaged bearings and failed shaft grounding devices. The goal is to definitively determine the type of bearing damage they are experiencing and to learn more about shaft grounding claims relative to their actual field performance.
shaft grounding systems' testing facility
Shaft Grounding Systems, Inc. has as its core principal the need to test and verify. For 30 years, being able to test not only our products for the long-term, but also the competition has kept SGSTM far ahead of the game.
Combining lab testing with actual long-term field studies has led to best in class performance. No extrapolating that leads to questionable product performance. For example, we completed an actual 10-year long field study across 1000s of continuously running VFD motors that led to us being able to claim the SGSTM CR Series shaft grounding system will run continuously for 10 years at 1800rpm prior to needing a quick brush change and all the while eliminating electrical bearing damage for the entire wear life of the brush.
impervious to the environment
All SGSTM non-drive end shaft grounding systems are impervious to the environment. Their brush running surface is fully sealed from dust, dirt, grease, etc. The grounding system to the right is installed on a blower motor and has been running for years. Rest assured though, the internal components responsible for maintaining a clean path of least resistance are perfectly clean. In addition, brush maintenance is done in just a couple of minutes and without shutting down the motor.
Small AC motors need class leading bearing protection: the CM series
This small AC motor was shipped to our factory for installation of the SGSTM CM Series shaft grounding system for small AC motors. We can accept motors up to 6000lbs should you determine its more convenient to have Shaft Grounding Systems, Inc. install your SGSTM devices. Shop rates apply.
the most robust, industrial grade ring system on the market: The SR Series split ring
This SGSTM SR Series split ring shaft grounding system was installed at a large sugar manufacturing plant where they were experiencing electrical bearing failure. Using the motor's existing retainer bolts, this system is easily field installed with handheld tools and no need to uncouple the motor. Its extreme robustness and industrial grade materials ensure this system will perform longer than any ring system on the market.
exposed? no problem for the sr series
With the exception of the SGSTM non-drive end models, shaft grounding systems, particularly ring systems, are exposed to the environment whether they are installed externally or internally to the motor.
Exposed running surfaces posses a special set of problems for every grounding system on the market (even internally installed) with the exception of the SR Series. Why? In short, it's so robustly built that it can withstand the harshest of environments. We understand that in order to function well in an industrial environment, the system must be very robustly built with large wear tolerances in order to maintain long-term performance. Thumb size carbon brushes, microfilaments that get gooped up with dust, dirt and grease simply don't qualify as industrial grade.
The SGSTM SR Series split ring is so robustly built that it currently operates at nuclear facilities where the grounding device is continuously bathed in salt water.
suspect circulating currents?
This SGSTM SR Series split ring was installed in a power plant on a 1000hp motor as a fail safe way of eliminating suspected circulating currents associated with larger frame motors. This end user also installed the SGSTM CL Series on the non-drive end to deal with capacitive discharge related to the VFD.
When circulating currents are suspected, we recommend grounding both motor ends rather than using insulated bearings/sleeves as these are extremely costly up front and are known to degrade over time leading to electrical bearing damage.
cl series for large motors
The SGSTM CL Series installed onto a 1000hp motor at a power plant. The big brother to the CR Series, the CL Series has an extra large brush to deal with larger currents that can be present in large from motors. It possesses all the same qualities including being field installable with handheld tools, maintainable on the fly and 10 years of class leading performance at 1800rpm prior to needing a quick brush change.
narrow axial shaft clearance?
No problem
This motor at a semiconductor plant was identified as having limited axial shaft clearance for installation of the standard SGSTM SR Series split ring. We quickly designed a custom system that required half the axial shaft space while possessing the same long-term performance as the standard system.
protect your investment
This turbo pump is outfitted with the SGSTM CR Series shaft grounding system for the non-drive end of the motor. This setup is bound for a semiconductor company that has a worldwide specification for SGSTM products as they have exhaustively studied their options for eliminating electrical bearing damage and have determine SGSTM is the only product that fits their strict reliability needs.
no need to uncouple the motor
This SGSTM SR Series split ring shaft grounding system was field installed at a semiconductor plant without uncoupling the motor. The existing bearing retainer bolts are used for the universal brush bracketing assembly so there is no need to drill and tap the end bracket.
HOspitals depend on long term performance of their motors
This SGSTM CR Series shaft grounding system was installed onto a 60hp Marathon motor using just handheld tools. DP&A Sales installed this grounding system as part of a lunch and learn at an Oregon hospital. The person who installed the device had no past installation experience showing that installation is simple.
Why rely on a light duty system for your large heavy duty motor?
The pictured SGSTM CL Series was field installed onto this large 345hp, ODP motor driving an amonia screw compressor. This particular motor had an internally installed microfilimant shaft grounding device as indicated by the shaft grounding name brand shown on the motor's name tag. The motor bearing electrically failed which led the end user to reach out to us for an actual long-term fix.
This grounding system possesses an extra large brush that is fully sealed from the environment and will maintain a path of least resistance for current to flow for the entire wear life of the brush which is expected to be 10 years at 1800rpm when running continuously.
When life needs to be protected
The SGSTM CR Series shaft grounding systems pictured are installed at a major aquarium in the western United States. These VFD pump motors operate sand filters for biological and mechanical filtration that keep their aquatic life healthy. This aquarium is dependent on their filtration systems and therefore have installed SGSTM onto their critical applications.
The pictured systems are at least 10 years old and are fully maintainable with a quick brush change that can be done without shutting down the motor. With a quick brush change, these motors will be expected to run continuously another 10 years at 1800rpm prior to needing another quick brush change.
3v or less is a must
Most brand-new shaft grounding devices can achieve the required voltage to prevent current from breaking through the dielectric and then to the bearing. The problem, however, is maintaining that target voltage for the long-term. Every shaft grounding device we've tested in our lab experiences voltage creep over a relatively short period of time. Some experience it faster than others, but none can perform for the long-term.
SGSTM shaft grounding devices will achieve shaft voltages well below what is needed to prevent electrical bearing damage, but more importantly these devices will maintain its out-of-the-box performance for the long-term.