Hydrocarbon Processing Copying and distributing are prohibited without permission of the publisher
Email a friend
  • Please enter a maximum of 5 recipients. Use ; to separate more than one email address.



Avoid unnecessary developments

05.01.2012  |  Bloch, H. P.,  Hydrocarbon Processing Staff, 

Keywords: [bearings] [seals] [mechanical seals] [wireless] [turbines] [steam turbines] [maintenance]

Innovative thinking is appropriate in the hydrocarbon processing industry, and tremendous forward movement has occurred over the past 30 years. Innovation is to be commended, unless we invent or discover something that others have already done in earlier decades. Duplication of efforts is found when people no longer read; unfortunately, entire technologies are sometimes reinvented due to negligence by not researching earlier information.

Case 1 experience

In this example, a major mechanical-seal manufacturer apparently developed a mechanical-seal assembly as a replacement for carbon rings used in the gland areas of small steam turbines. However, 20 years earlier, this type of steam turbine seal gland upgrade cartridge (STSGUC) had been pursued and fully implemented by a user company in Texas. A conference paper was then written and presented at an American Society of Lubrication Engineers (ASLE) conference in 1985.1 Several manufacturers of small- and medium-size steam turbines were contacted by the Texas-based STSGUC users. But the manufacturers showed no interest in commercially developing cost-justified STSGUC retrofits.

Later, a major seal manufacturer started marketing STSGUC-like products. Could the manufacturer have saved money by investigating earlier developments? Could they have saved time and effort by researching the 1985 product releases? If the design team examined the matter, then why wasn’t there an acknowledgment to the conference paper and article that pointed the way?

Case 2 experience

Recently, a company developed a bearing mounting arrangement that could accommodate vertical shafts. Apparently, the effort was in response to bearing failures with vertically oriented cooling fan shafts. Again, the developers were oblivious that well-established major bearing manufacturers had, for a long time, been providing spherical roller bearings with thrust load and angular misalignment capabilities. This knowledge could have saved money spent on developments that were largely a duplication of prior work.

Case 3 experience

In 2009, a startup company began commercializing technology aimed at capturing bearing degradation before it had progressed to failure. It is a predictive maintenance (PdM) approach, which could be best described as Bearing Housing Metal Stress Propagation Sensing. When asked for more data, it became evident that the company staffers had not read pre-existing conference proceedings, articles or chapters in books dealing with a pump PdM method known as incipient failure detection (IFD). Fig. 1 shows IFD transducers mounted on an electric motor driver and a pump bearing housing. In the early 1980s, several publications had highlighted IFD technology and explained why a major multinational petrochemical company in the US had discontinued supporting its IFD program.2 The short explanation is that each baseline electronic signature (displayed on the 1970s monitor in Fig. 2) is different from the next. 

  Fig. 1.  Acoustic IFD transducers mounted on a
  pump and its electric drive motor. The high-
  frequency amplitude excursions signaled
  bearing defects.3


  Fig. 2.  Acoustic IFD monitoring station, 1976.


There was no cost-effective way to accurately predetermine an intervention threshold. Until such thresholds are defined and incorporated in a cost-effective, wireless signal transmission technology, the developments will meet with low user interest. Then again, good books may shed much light on similar issues.3 HP

LITERATURE CITED

1
Bloch, H. P. and H. Elliott, “Mechanical seals in medium-pressure steam turbines,” Lubrication Engineering, November 1985.
2 Bloch, H. P. and R. Finley, “A decade of experience with plant-wide acoustic IFD systems,” Vibration Institute Conference, Houston, Texas, April 1983.
3 Bloch, H. P., Pump Wisdom: Problem Solving for Operators and Specialists, John Wiley & Sons, Hoboken, New York. 2011.

 The author

Heinz P. Bloch is Hydrocarbon Processing’s Reliability/Equipment Editor and a consulting engineer residing in Westminster, Colorado. Mr. Bloch is the author of 18 comprehensive texts. He is an ASME Life Fellow. 




Have your say
  • All comments are subject to editorial review.
    All fields are compulsory.

Related articles

FEATURED EVENT


Sign-up for the Free Daily HP Enewsletter!

Boxscore Database

A searchable database of project activity in the global hydrocarbon processing industry

Poll

Should the US allow exports of crude oil? (At present, US companies can export refined products derived from crude but not the raw crude itself.)


64%

36%




View previous results

Popular Searches

Please read our Term and Conditions and Privacy Policy before using the site. All material subject to strictly enforced copyright laws.
© 2014 Hydrocarbon Processing. © 2014 Gulf Publishing Company.