Last updateFri, 28 Oct 2016 1pm


Mining: Are We There Yet?

Mining: Are We There Yet?

In the U.S., mining is largely about oil...

Warriors, Welding and Wooing the Workforce

Warriors, Welding and Wooing the Workforce

For the last several years, one of the b...

New Test Standards for Low-E Compliance

New Test Standards for Low-E Compliance

Creating practical, unified standards fo...

The Weekly Report

New Products

  • ja-news-2
  • ja-news-3

Industry Headlines

U.S. Economy Grew 2.9% in the Third Quarter

Friday, 28 October 2016  |  Chris Guy

Real GDP in the U.S. increased at an annual rate of 2.9% in the third quarter of 2016, according to the advance estimate released today by the Departm...



Industry Headlines

Honeywell and Flowserve Collaborate on IIoT Solutions


Honeywell and Flowserve will collaborate to provide Industrial Internet of Things (IIoT) for industrial customers. The collaboration will be part of the Honeywell INspire program, Honeywell's joint customer development program for its IIoT ecosystem.

Honeywell and Flowserve have a long history of colla...


Train Named Executive President of Emerson Automation Solutions


Emerson recently named new senior leadership appointments to its Office of the Chief Executive who now report directly to chairman and CEO David N. Farr, and help develop and guide the company’s global strategies.

Michael H. Train’s new title is executive president of Emerson Automation Sol...


Offshore Production Nearly 30% of Global Crude Oil Output


Global offshore oil production (including lease condensate and hydrocarbon gas liquids) in 2015 was at the highest level since 2010, and accounted for nearly 30% of total global oil production. Offshore oil production increased in both 2014 and 2015, reversing consecutive annual declines from 2010 t...


New 2017 Construction Starts Increasing 5% to $713 Billion


The 2017 Dodge Construction Outlook predicts that total U.S. construction starts for 2017 will advance 5% to $713 billion, following gains of 11% in 2015 and an estimated 1% in 2016.

Manufacturing plant construction will increase 6%, beginning to recover after steep declines in 2015 and 2016 that refle...


U.S. Economy Grew 2.9% in the Third Quarter


Real GDP in the U.S. increased at an annual rate of 2.9% in the third quarter of 2016, according to the advance estimate released today by the Department of Commerce. This is the highest figure in two years and slightly better than economists had predicted. In the second quarter, real GDP increased ...


Richmond Fed: Manufacturing Rises But Remains Sluggish


Manufacturing activity fifth district (MD, DC, VA, WV, NC, SC) remained sluggish in October, according to the most recent survey by the Federal Reserve Bank of Richmond. New orders and backlogs decreased this month, while shipments flattened. Hiring activity strengthened mildly across firms and wage i...


Grease for Motor Actuator Maintenance

Maintaining the right amount of grease inside motor actuators that use grease for lubrication is a vital part of valve maintenance, and can save time and money by preventing problems before they happen. Inadequate lubrication is often the culprit in a malfunctioning motor actuator, and understanding how to effectively manage grease in motor actuators can be a simple way to keep costs down and to keep actuators out of the repair shop.

Motor actuators must have the correct amount and type of grease in the gear case to provide for trouble-free operation.


Getting Inside
The first step is getting inside the actuator. Actuators have from two to four grease plugs to allow adding and checking the level of grease. The quality, quantity, and consistency of the grease in the actuator should initially be checked every 18 months, then at a frequency derived from the results. This inspection must be accomplished through these grease plugs.

Motor actuators are built to operate on the partial immersion principle. What matters is whether or not the "worm" is totally immersed in grease. This is to ensure that the efficiency of the worm/worm gear set is operating at its highest level, because this gear set is the most inefficient gear set in the actuator, operating at about 20% to 25%.

Due to the heat of the sun or system operation, the gear box is pressurized, which is why just filling up the gear box with grease causes the grease to push through the seals and into the motor windings and/or into the limit switch compartment.

To determine the correct amount of grease to add to a gear box, perform an inspection by using one of the many "fill and drain" plugs to ensure the worm is totally immersed in grease. When the actuator is mounted in a different orientation, the amount of grease needed to totally immerse the worm will change.

If your actuator is disassembled for repairs or rebuilding, these grease plugs should all be removed, cleaned, and reinstalled. Sometimes these plugs will be corroded in the housing and must be drilled out. Due to the metal chips that will fall into the grease, don't drill them out during operation. Instead, remove them during the rebuild when the inside is exposed.

The drive sleeve in an actuator extends through the housing on both the bottom and top sides. A seal is used to prevent leakage of grease at this penetration. The lower drive sleeve is held in place by a seal retainer, which is installed and removed, from the bottom of the actuator. This seal retainer is held in place by screws, bolts, or just a press fit on different sizes of actuators.

When the actuator is disassembled for repair or rebuild, this seal retainer does not need to be removed to fish out the seal and replace it. However, it should be removed to allow the rebuilt drive sleeve to be installed first. If the seal is installed first, and then the drive sleeve, there is no way to ensure that the seal is not nicked or rolled during the drive sleeve installation.

Grease in the main gear box will not flow into the clutch housing compartment of the actuator, so this compartment must also have grease added to cover the motor pinion/worm shaft clutch gear set. Fill this area just enough to cover the gear set-not too full.

The actuator can be mounted in any position since it has a totally sealed gear case. However, mounting positions that would cause vulnerable areas of the actuator (e.g., motor and limit switch compartment) to be saturated with grease in the event of a seal failure are not recommended.

The Right Grease
Use only the correct type when adding grease to your actuators. This means the grease must:


  • contain an "EP" additive
  • be suitable for the temperature range needed
  • be water and heat resistant and non-separating
  • not create more than 8% swell in Buna N or Viton seals
  • not contain any grit, abrasive, or fillers
  • not slump-preferred NLGI grade 0 to 1
  • not be corrosive to steel gears, ball, or roller bearings
  • have a dropping point above 316° F for temperature ranges of -20° F to 150° F.

In addition to the above, keep in mind that grease is made up of a filler (soap) and oil. Different types of fillers are used and not all types will mix well with each other. If you are going to add grease, use the same type of grease in the gearbox or ensure the new grease is compatible.

Regularly checking the level and quality of grease inside motor actuators will provide results that speak for themselves. Quite literally, proper lubrication makes a motor actuator function more smoothly, and keeps it lasting longer and working at maximum efficiency at very little cost.

  • Latest Post

  • Popular

  • Links

  • Events


Looking for a career in the Valve Industry?

ValveCareers Horiz

To learn more, watch the videos below or visit ValveCareers.com a special initiative of the Valve Manufacturers Association