Category Archives: Uncategorized

SealFAQs, Uncategorized

A Rant

Fair warning: This is a rant.

I had to stop all comments because a certain person continually entered fake comments just to promote his own websites. I don’t understand how or why this person does this, but the only way I could prevent it was to not allow comments on any posts.

I’ll leave this post open to comments so I can test my latest options for preventing spam. If your website or email address uses words like ‘hairstyle’, ‘hair’, ‘style’, ‘hairstylevip’, etc. then you may not be able to comment – at least I hope so.

Of course, the spammer does not actually read my posts, so this message may go unnoticed, but I’ll leave this post up for a few days and see what happens.

Novel, Uncategorized

The Viking Princess: College Romance in 1970

My second novel, “The Viking Princess: College Romance in 1970,” has been published on Amazon, see https://www.amazon.com/dp/B09MYSS2T1 . No, I didn’t crank it out in a couple of weeks. In 2021, I actually wrote two novels. Here’s the explanation.

In writing “Timepath: Nature Abhors a Paradox”, https://www.amazon.com/dp/B09LGV94RL, I needed lots of study and help and signed up for online classes. Then I needed a practice novel for the online classes, so I created “Viking Princess”—a ridiculous “Hallmark Movie” kind of novel in which anything is possible. “Viking Princess” soon turned into a romance novel and, rather than change its genre, I determined to take on the challenge and finish it.

“Viking Princess” was a lot of fun to write and I was encouraged to publish it. Why not? I hired an artist and described the characters and scenes. Seeing her illustrations convinced me to publish “Viking Princess.”

*****

Fiona is an auburn-haired Scottish orphan called ‘Viking Princess’ because of her height, beauty and regal bearing. She is a serious, but shy, fine art student and keeps to herself. Fiona stereotypes football players as dumb bullies. Her new friend, Mary, wants to introduce Fiona to her best friend, Alexander.

Alexander is the Big Man on Campus. A handsome engineering student and star football player, his ambition is to become an inventor. Everything is easy for Alexander. Mary describes Fiona as ‘having a good personality’—intentionally not mentioning her beauty — and Alexander reluctantly agrees to meet her.

As they become acquainted, Fiona and Alexander must overcome cultural differences, jealousy, punishment for PDA, harassment, and family.

Uncategorized

Timepath: Nature Abhors a Paradox

Timepath

For the past year, inspired by my grandfather, J. W. Hale, I’ve been attempting to reinvent myself as a novelist. As an avid reader, I always wanted to write novels, and had made various unsuccessful attempts over the years. Finally, I realized that, at nearly age 24 °C, I had better get busy if I were ever to write my novel.

Time travel has always fascinated me and my own time travel novel was first on my bucket list of writing. I collected my pieces and snips and began writing my novel. It was a disaster–too much engineer, bad habits, and ignorance of organization. I signed up for several online novel writing classes and submitted many rough drafts and samples for criticism.

And now, I have finished my novel! “Timepath: Nature Abhors a Paradox” is entirely different from the novel I first imagined, but I can put a big check mark on my bucket list!

The paperback version is on Amazon at https://www.amazon.com/dp/B09LGV94RL

The ebook version is on Amazon at https://www.amazon.com/dp/B09LSM6YLC

“Timepath: Nature Abhors a Paradox”

When Greg learns that his romantic interest, Anne, is actually his sixth great-granddaughter and is susceptible to breast cancer, he joins an experimental time travel project based on the twisted string theory of time. Although his official mission is to be briefly transported to 1810, his personal mission is to remain and administer a cancer preventative. The time travel team is baffled by Greg’s disappearance and attempts to discover the reason. Anne remains in 2022 and defends Greg’s reputation. Greg and Anne devise a method for Greg to save artifacts, letters, and photographs from the early 1800s where he must learn to live. They each make a time capsule to record their lives.

Uncategorized

Drain and Bushing Flow in Piping Plans 66 A/B

Leakage detection and management is a major consideration in the application of mechanical seals.  Some arrangements and configurations can be fitted with drain connections and a throttle bushing to force leakage through that drain.  Leakage through the throttle bushing remains near the gland plate whereas leakage through the drain can be piped away from the seal/pump.  Piping Plans 65A/B and 66A/B are special piping plans for leakage detection and management but a simple run of pipe connected to the drain can also be used to route leakage to a disposal area.

An open drain means that all leakage will remain near the seal/pump.  A plugged drain means that all leakage will go through the throttle bushing and remain near the seal/pump.  Even a close clearance throttle bushing has little effect on reducing seal face leakage.

How large should the drain be in relation to the throttle bushing clearance?  API 682 4th Edition provides some guidance.  Fixed throttle bushings have a diametral clearance ranging from 0.025 to 0.040 inch.  Floating carbon bushings have a diametral clearance ranging from 0.007 to 0.011 inch.  A segmented variation of the floating carbon bushing typically rubs the sleeve slightly but performs as though the diametral clearance was 0.001 to 0.002 inch.  The drain connection is typically 3/8” NPT but the drill through to the connection is more like 1/4” or 3/8” diameter.  Piping Plan 66B uses either a 0.0625 or 0.125 inch diameter drilled hole in a plug placed in the drain connection.

Following is a simplistic procedure for estimating leakage rate and distribution to the drain and throttle bushing.

Plan 11 - with seal - Drain Calculations
Plan 11 – with seal – Drain Calculations

As shown in the figure above1, seal face leakage is from P1 to P2.  All seal face leakage must exit through either the throttle bushing or drain piping.  Throttle bushing and drain leakage is from P2 to P3.  The pressure P2 must be sufficiently high to force all the seal face leakage through the drain piping and bushing.  An increase in P2 also means a decrease (typically negligibly small) in seal face leakage.

There is no closed form algebraic solution for the analysis of this problem.  However, by combining simple equations for seal face leakage, throttle bushing leakage and pipe flow, a trial and error approach can be developed to approximate the various flows.  First, an estimate is made for P2.  Using this estimated P2, seal face leakage can be determined.  Next the flow through the drain piping is determined based on P2.  Flow through the bushing is also calculated based on P2.  The sum of the drain and bushing flows must equal the seal face leakage otherwise a new estimate is made for P2. This trial and error procedure is repeated until convergence is obtained.

A number of trial cases were established and solved to get a feeling for the procedure and results.  It quickly became apparent that as the throttle bushing clearance is reduced, almost all seal face leakage goes through the drain.    Of course, it is the throttle bushing that forces flow to the drain and large throttle bushing clearances render the bushing less effective. 

Drain and Bushing Calculation Composite
Drain and Bushing Calculation Composite

The same equations and procedures could be applied to Piping Plan 66B even though the illustration for Piping Plan 66B.  For more information and details, see Piping Plan 66B.

Analysis of Plan 66A is slightly different because of the dual throttle bushings.   For more information and details, see Piping Plan 66A.

The following conclusions may be drawn from this study:

  1. Except for very high seal face leakage rates in designs using fixed bushings, virtually all seal face leakage is routed through the drain connection.
  2. Floating or segmented throttle bushings (that is, not fixed bushings) should be used in Piping Plan 66A&B and the alarm pressure probably should be set to less than 1 psig.
  3. Piping Plans 66A&B are suitable for detecting sudden large leakage rates but not monitoring leakage trends.
  4. Piping Plan 66A is much more sensitive to leakage rates than Plan 66B.
  5. Within the recommendations of API 682 4th Edition, the size of the drain piping, drain orifices and the clearance of the throttle bushing produce the trends shown in Table 1.  Note that leakage from the outer bushing becomes environmental leakage at the pump unless drain piping is provided.  The relative effects shown in Table 1 increase with increased seal face leakage rate.
Table Showing Relative Effects of Variables
Table Showing Relative Effects of Variables
Uncategorized

Metal Bellows Seals

Several requests had been made for engineering guidelines regarding metal bellows seals.  Although I like metal bellows seals, I don’t consider myself expert in their design.

SealFAQs does include some comments and anecdotes about metal bellows seals including the history and development of stationary metal bellows seals but no real details about design or application.

Fortunately, John Crane has recently published “Seven Things to Know …” about metal bellows seals in their blog. 

Uncategorized

Buck Family of Virginia Book

Not exactly related to mechanical seals but I’ve published a genealogy book about my Buck family.  It is available as an ebook on Amazon and will soon be available as a printed book.  See https://www.amazon.com/dp/B0847R7WG8/ref=nav_timeline_asin?_encoding=UTF8&psc=1

My Buck family is usually referred to as the “Buck Family of Virginia”.  The first member of the Buck family to come to the New World was the Reverend Richard Bucke who sailed from England on June 2, 1609 for Jamestown on the Seaventure. He was the second minister of the Virginia colony and is probably best known for performing the marriage ceremony of John Rolfe and Pocahontas in 1614.

The progenitor of my Buck family of Virginia was Thomas Buck (1618 – 1659) who left Gravesend, England for Virginia on August 21, 1635 onboard the ship George when he was seventeen years old. There is no known relationship between Thomas Buck and the Rev. Richard Bucke but there are several interesting, if perhaps circumstantial, similarities. They were from the same general area in England and settled into the same area in Virginia. It seems highly likely that Thomas would have known the children of Richard Bucke.

In Virginia, Thomas Buck settled into York County, Virginia and appeared to have been prosperous; however, he died at the age of 41.  His will includes an inventory of his household goods which includes, among other things, a Bible and 8000 nails.  There is little information on his children and grandchildren except for his great grandson Charles.

Charles Buck I was born about 1710 in York County and died in 1771 in the Shenandoah Valley. The three sons of Charles Buck I married three daughters of William Richardson and Isabella Calmes in 1774. These three families had thirty-two children. I am a descendant of Charles Buck II through his son William Calmes Buck.

Although the Buck family is not often mentioned in history books, they were a prominent and well-to-do plantation family in early Virginia. They were active in the local economy, politics and religion of the Shenandoah Valley during the 1700’s and 1800’s.  In the 1800s, many family members moved westward, especially into Kentucky, Alabama, Mississippi and Texas.

The Buck family of Virginia also has connections to the Calmes, Ashby, Blakemore, Field, Helm, Neville, Payne, Pierce, Thomas, Bayly, Catlett, Sorrell and Mauzy families of Virginia and Maryland.  Later, a strong connection to the Harrison family was developed in Texas.

All of this information and more is contained in the book.  Most of it is also in my genealogy blog at http://buckfamilyofvirginia.blogspot.com/

API, mechanical seal, SealFAQs, Uncategorized, Wikipedia

Blogs about Mechanical Seals

A blog is a “weblog”, that is, an online journal or informational website.  Posts to a blog appear in reverse chronological order. A blog can be about anything. Many blogs are personal in nature and often are similar to a diary.  The first blogs began to show up about 1994 and were primarily text with a single author.  A blog is expected to be updated more frequently than a website and also to be somewhat less formal.  Blogs usually have a byline or author and the blog site includes the ability to find previous posts by author, date, category and tags.

A blogger is simply someone who operates a blog or blog site as opposed to someone who authors a post for a blog or website.

Blogs can generate money through sponsors and links to commercial sites; however, SealFAQs does not do this.

One problem with hosting a blog is the commitment to maintain it and to add new posts regularly.  Having neglected my own blog for several months, I’m well aware of this problem.  After a while, the newness and uniqueness of the blog sort of wears off and the blogger runs out of things to write about.  Fortunately, I have plans and topics for 2020.

Manufacturers Blogs

There are several different types of blogs.  Some seal OEMs operate a corporate blog to provide information and updates about their products.  Here are some links to OEM “blogs” that are specifically labelled blogs.

John Crane has a blog, https://resources.johncrane.com/blog/, attached to its main website, JohnCrane.com.  The Crane blog addresses a variety of subjects and appears to be somewhat irregularly updated.  The Crane blog appears to be a mix of technical articles, product announcements, news and field experience.  The author(s) name is not given.  The Crane blog began December 13, 2018.

Chesterton has a blog, https://blog.chesterton.com/, attached to its main website, Chesterton.com.  The current topic is part 4 of a series on double seals and barrier fluids; it dates to October 31, 2019.  Although good information, the overall feel is not that of a “blog”.  Apparently several authors contribute.  The Chesterton blog dates back to at least 2017.

Sepco has a blog, “Seal Connect”, at https://www.sepco.com/community/blog/, with posts by various authors dating back to July 23, 2019.

Flowserve does not appear to have a blog, as such. 

EagleBurgmann does not appear to have a blog, as such. 

Non-Manufacturers Blogs

SealFAQs is not a manufacturer sponsored blog.  There are a few other such blogs, but not many.

The Fluid Sealing Association (FSA), the International Trade Association for mechanical seals, has a blog, http://www.fluidsealing.com/mechanical-seals/mechanical-seals-blog/.  The FSA blog doesn’t feel like a conventional blog.  Posts tend to come from the various member companies of the FSA.  Many of the FSA posts were published in Pumps and Systems Magazine as part of the “Sealing Sense” series.  The most recent post was published in June 2019.

There is a relatively new blog at https://www.mechanicalseals.net/Mechanical-Seal-Blog/index.php?frontpage, with the title “Mechanical Seal Tips and Details”.  It has only three posts and has the feel of a project that was undertaken and then stopped.  However, it was off to a good start.

Seal Websites

Of course, there are other websites containing information about mechanical seals and a few use the word “blog” in their description but don’t really have the feel of a blog.

Wikipedia has a page for mechanical seals, https://en.wikipedia.org/wiki/End-face_mechanical_seal as well as a page for the seal standard, API 682, https://en.wikipedia.org/wiki/API_Standard_682.

If you are aware of other mechanical seals blogs and especially if you have a favorite mechanical seals blog, please leave a comment.

Uncategorized

SEALFAQS STATISTICS FOR 2019

The SealFAQs site did well in 2019 even though I sort of neglected it the past few months.  SealFAQs is alive and well and I have a number of updates and articles to add.

SealFAQs has been officially launched for two full years.  Here are the statistics for 2019 according to Awstats (Advanced Web Statistics):  SealFAQs had 33,020 unique visitors during 2019 and a total of 49,521 visits (1.5 visits/visitor).  Visitors averaged looking at 3 pages per visit.  Total bandwidth was 26 GB. 

Most days, SealFAQs has about 120 to 150 visitors but it is not unusual to have around 200 visitors. The most visits in a day during 2019 was 305.   As usual, most people visit during the week and the middle part of the day.  There has always been a drop off in visits on the weekends and during a holiday season.

By far, the most visitors to SealFAQs are from the United States and distantly followed by Thailand, India, Russia, Ukraine, Sweden, Canada, Great Britain and Germany.

The average time of a visit to SealFAQs is about 4 to 5 minutes in duration but this average is probably because a few people log in for hours.  More than 80% of all visits are for less than 30 seconds. 

Access to SealFAQs via search engines is usually based on key phrases related to piping plans. 

I check SealFAQs for comments every day.  SealFAQs finally has some legitimate comments instead of the bits of spam or faked comments that show up daily. 

I was especially pleased to have added a history of John Crane – the Person during 2019. 

bellows seal, mechanical seal, pusher seal, Uncategorized

Mechanical Seals in Chaos

1 Comment

In retirement, I’ve had time to contemplate the meaning of life and mechanical seals.  With mechanical seals, as with life, things have not always worked out the way I thought they would.   I’ve come to believe that mechanical seals, like life, are near-chaotic systems.

Chaos is sometimes defined as complete confusion and disorder.  If Chaos is complete confusion then Chaos Theory is the mathematics that attempt to explain it – or at least show how Chaos cannot be explained or controlled. 

One characteristic, perhaps the easiest to understand, is that chaotic systems have such a strong dependence on initial conditions that the outcome appears to be random.  Chaos was summarized by Edward Lorenz as “When the present determines the future, but the approximate present does not approximately determine the future.”

Non-linear systems sometimes respond in an apparent chaotic manner.  It is important for engineers to realize that our day-to-day mathematical methods often use extremely linearized versions of non-linear systems.  Anyone who applied engineering mathematics using a slide rule can readily appreciate this linear simplification; however, many computer programs still use the same linear simplifications that we fully mature engineers learned to use on our slide rules.

Examples of potentially chaotic simple systems include:

    • Spring-mass system (with non-linear spring) with damping
    • Fluid flow, especially for turbulent flow regimes
    • Any process relying on friction
    • Any process having wear
    • A dripping faucet
    • Stick-slip sliding
    • Thermosiphon systems (flow direction can reverse).

Any of the above examples seem familiar?  Let’s see where Chaos Theory might apply to mechanical seals:

    • All seals have some sort of spring; spring force is a function of seal position (setting)
    • Metal bellows seals have little damping
    • O-rings provide damping but are dependent on lubrication and surface finish
    • Fluid flow patterns around seals are dependent on flush rate (and fluid type, rpm, clearances, etc.)
    • Seal face friction is dependent on material combinations and lapping (not to mention speed, load, fluid, leakage, etc.)
    • Seal face wear rate depends on face load, friction, materials, lapping, fluid, leakage, etc.
    • Shrink fits affect seal face flatness and waviness
    • Stick-slip sliding between seal faces is a well-known phenomenon, especially with metal bellows seals
    • Piping plans for seals sometimes rely on thermosiphon effects.

Not to mention venting!

We certainly want and expect a consistent performance from mechanical seals.  Let’s look at how this might be accomplished.

An often overlooked aspect of mechanical seals is the surface finish (roughness) of the faces.  Most people know the importance of lapping a seal face to near perfect flatness but the surface finish is also extremely important.  Surface finish is measured in millionths of an inch and can vary considerably with the material, manufacturer, even batch.  Also, many suppliers do not check surface finish regularly but rely on the manufacturing process for consistency.  Some suppliers may not even have the equipment to check surface finish.

The flush rate to a seal is important not only for traditional heat balance considerations but for establishing the flow pattern around the seal.   More – or less – flush is often given credit for solving seal reliability problems when the effect may be due to flow pattern and not traditional heat balance.

Other approaches to minimizing chaos in mechanical seal performance include: 

    • Designs employing damping (“pusher” seals)
    • Monolithic designs instead of shrink fitted designs
    • Cartridge seals have a more consistent assembly and therefore consistent spring load
    • Consistency in selecting materials for repaired seals
    • Don’t rely on thermosiphon effects
    • Vent!  Vent! Vent!  Don’t attempt to startup with air in the system.

A more appropriate title for this post might have been “Mechanical Seals and Chaos Theory”; however, that title appears a bit more academic than this post actually is.  Besides, I really don’t know Chaos Theory but surely it applies to mechanical seals!  Perhaps someone with more up-to-date skills in mathematics will apply those skills to studies of mechanical seals and provide guidelines to preventing chaos. 

API, API 682, bellows seal, mechanical seal, Uncategorized

API 682 is Not a General Purpose Standard

In spite of all its excellent specifications, recommendations, tutorials, etc., etc., API 682 is not a general purpose standard for mechanical seals.  Here is a partial list of seals that API 682 does not address:

  • large seals
  • high pressures
  • mixer seals
  • rotary pump seals
  • wedge/chevron/ucup
  • outside mounted
  • common mating ring
  • shaft mounted
  • hook sleeve mounted
  • automotive water pump seals
  • stern tube seals
  • split seals
  • elastomeric bellows seals.

It appears that the 5th Edition of API 682 will include somewhat larger seals and higher pressures.  Mixers and rotary pumps could, of course, use API 682 seals provided those seals would fit into the seal chamber.  Wedges, chevrons or U-cups for dynamic secondary sealing elements were intentionally omitted in favor of O-rings.  Outside mounted seals were intentionally omitted in favor of inside mounted seals.  Shaft mounted seals and hook sleeve mounted seals were omitted in favor of cartridge mounted seals.  Dual seals using a common mating ring were omitted in favor of requiring a mating ring for each seal ring.  Automotive water pump seals as well as similar small utility seals and stern tube seals are far outside the scope of API 682.  Split seals have very different design for special applications and were never considered for inclusion in API 682.

Interestingly, API 682 does not address one of the earliest, most popular and proven mechanical seals:  the elastomeric bellows seal.  The omission of elastomeric bellows seals was intentional because some members of the 1st Edition Taskforce felt that elastomeric bellows seals were difficult to install.  This can be true; however, since API 682 considers only cartridge seals, installation of elastomeric bellows seals is simplified and furthermore would be done by the seal OEM.

Elastomeric Bellows Seal

In the mid 1930’s Crane Packing Company licensed a mechanical seal design from Chicago Rotary Seal. By the late 1930s, mechanical seals began to replace packing on automobile water pumps.  At first only the more expensive automobiles used mechanical seals in the water pump. The famous Jeep of WWII used a Crane elastomeric bellows seal in the water pump.  After WWII, all automobile water pumps used mechanical seals. Through several Crane patents, their design evolved into the full convolution elastomeric bellows seal of today.            

In 1943, under the direction of Carl E. Schmitz and designed by Russ Snyder, Crane Packing Company began work on what became its Type 1 and Type 2 rubber bellows mechanical seals.  Don Piehn, a draftsman still in high school, did the detailed drawings.  The Type 1 and Type 2 seal names were adopted about 1946.  Prior to 1946, Crane seals did not have number/type names.  The Crane seals that had been used in WWII jeeps and later other automobile water pumps came to be called the Type 3 and Type 4 but actually preceded the Type 1 and Type 2. 

Today, there are many manufacturers of elastomeric bellows seals.  Elastomeric bellows are very popular and also very reliable but they are not considered by API 682.