Thread Seal Tape, a Fitting Friend

Tips From the Service Bench

By design, vacuum pumps pull gas or liquid in on the inlet side and expel media on the exhaust side. One prevalent issue to avoid, in order to ensure that the pump keeps operating to full potential, is keeping unwanted material out of the pump head and valves.

Many vacuum pump plumbing connections are made with hose connectors and fittings. One standard fitting thread is the National Pipe Thread (NPT). The threads on an NPT fitting are tapered for sealing, and are often used with a thread sealant, such as Thread Seal tape.

A recurring issue seen by our Service Department is loose Thread Seal tape unintentionally ingested into a pump (see photos below). The loose tape gets pulled in by the vacuum and lodges between the valve and valve seat. This can result in a loss of performance in the system and headaches for the pump user. The cause of this reduced performance is often not readily apparent, either.

Figure 1: Actual photos of ingested Thread Seal tape found within pump heads.

Once ingested, tape will not be expelled on its own as the path through the pump head is not designed to allow long/stringy solids to move through it. The removal of the tape debris involves disassembly of the pump head assembly, removal of the tape and re-assembly after inspection of all the components. This is time consuming and can be avoided.

One way to avoid ingested Thread Seal tape is to understand how the tape works in conjunction with the fitting and threaded port hole. The taper on NPT threads allows them to form a seal when torqued, as the flanks of the threads compress against each other. The fittings seal on the actual thread of the fitting and the hole. The fitting does not necessarily have to be installed to full thread depth as it is sealing on the thread itself.

DO’S

Figure 2: Apply Thread Seal tape

• Wrap the tape clockwise (facing the threaded portion) so that it follows the direction that the fitting will be threaded into the port (see Figure 2). Winding the tape in this direction will prevent the tape from unwinding during the tightening process.

• Use a Thread Seal tape that is narrow enough so it does not cover the first two threads of the fitting (see Figure 3). The first of the male fitting threads are the smallest in diameter and any tape wound onto these threads may actually be cut off as the fitting engages. The cut off tape may then be pulled into the pump head by the gas or liquid flow.

Figure 3: Correct application of Thread Seal tape

• Use 2-4 wraps of Thread Seal tape. You may need to adjust the number of wraps due to specific tolerances.

• Start the fitting by hand to ensure no cross threading occurs.

• Tighten according to fitting manufacturer specifications.

DONT’S

Figure 4: Incorrect application of Thread Seal tape

• Don’t wrap the tape covering the bottom of the fitting. Leave two threads free of tape (see Figure 4).

• Don’t feel the need to tighten fitting until the hex is flush. The sealing occurs on the tapered thread. It is OK if a few threads are left visible as long as the fitting is tightened to the manufacturers specified torque.

WRAP UP

Learning to apply Thread Seal tape properly will serve you well. When used properly, Thread Seal tape is a wonderful sealant. It is inexpensive and works in many different applications. It is easy to apply and lubricates the fitting and threaded hole assembly process. It also prevents possible corrosion at this interface and aids fitting removal.

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New Flow-Tight, Diaphragm Liquid Transfer Pump Prevents Uncontrolled Flow

New, FL 10 Diaphragm Liquid Transfer Pump Prevents Uncontrolled Flow

KNF’s newest liquid transfer pump, the FL 10, is leak-tight in both directions, preventing uncontrolled flow and back-flow of liquid media when not in use. The latest addition to KNF’s extensive line of diaphragm liquid transfer pumps, the FL 10 offers many advanced features, and provides a considerable advantages over similar competitive products.

Leak-tight Diaphragm Liquid Transfer Pump

Featuring a solenoid-drive, and leak-tight valve technology, the compact FL 10 liquid transfer pump displaces fluid at a flow rate of 0 – 100 mL/min. Additionally, a signal frequency modulation feature enables quick and easy flow rate adjustments, saving time and money. Finally, like all KNF diaphragm liquid handling pumps, the FL 10 is self-priming, dry-run safe, and maintenance-free – offering outstanding performance longevity and an extraordinarily long service life (10,000 hours or 1.8 billion strokes).

To learn more about the leak-tight FL 10 liquid transfer pump visit knfusa.com/FL10

New KNF Laboratory Products Catalog Available

KNF Neuberger Inc. has recently published an updated Laboratory Products Catalog. The 33-page catalog reflects the newly expanded range of laboratory products offered by KNF Neuberger, Inc. which includes: a complete line of vacuum pumps and accessories, liquid transfer pumps, dosing/metering pumps, rotary evaporators, and vacuum systems.

Organized by application, this comprehensive guide presents the best product selections for rotary evaporation/distillation, degassing, filtration/SPE, fluid aspiration, gel drying, centrifugal concentration, vacuum ovens, multi-user vacuum systems, and metering and transferring liquid. In addition, this piece includes handy product charts for easy comparison.

View the new Laboratory Products Catalog here. Or, request a high-resolution printed version via postal mail by completing the form below.

KNF Exhibiting at the World’s Largest Printing Equipment Show

reprographic printingAs a trusted partner to many of the world’s leading industrial reprographic printer manufacturers, KNF is preparing to showcase its latest product developments at Drupa 2016. Considered the world’s largest printing equipment exhibition, Drupa is open every three years in Dusseldorf, Germany. This year, the show runs from May 31st through June 10th, and KNF is excited to be a part of it.

At the show, KNF will be exhibiting its latest product developments including liquid pumps with flow rates from microLiters/min to 12 L/min+ and gas pumps with flow rates from microLiters to 300 L/min. Additionally, KNF offers a wide selection of pumps that can be optimized for specific needs through engineer-to-engineer collaboration. Optional materials, motor types, fluid connections and other modifications are available to optimize performance, life, and cost at any quantity.

KNF liquid and gas pumps perform important ink handling tasks, including the ink transfer to print heads, ink degassing, print head cleaning, vacuum generation for print head meniscus control, and ink circulation. From continuous inkjet to drop-on-demand, from large format printing to product barcoding, KNF has the pumps needed for high-quality, consistent printing.

Please plan to stop by our booth in Hall 4, booth B01 if you will be attending Drupa 2016. To learn more about KNF pumps for reprographic printing visit www.knfusa.com/reprographics or read our related Application Notes:

KNF’s Laboratory Symposium Offered an Evening of Exploration and Learning

Last week, KNF Neuberger Inc. hosted a Laboratory Pumps and Applications Symposium in collaboration with the Trenton Section of American Chemical Society (ACS). The event, a first of its kind, attracted attendees from local academia and industry.

Beginning in the early evening, the Lab Symposium kicked-off with a mixer featuring beverages and hors d’oeuvres. Attendees became better acquainted with each other, and more familiar with KNF laboratory equipment which was on display throughout the room. Soon after, guests were invited to a guided tour of KNF’s 50,000 square foot manufacturing facility. The tour, led by KNF Director of Sales and Marketing, Eric Pepe, allowed symposium guests to view important aspects of KNF’s pump production area including: assembly and testing stations, high-tech machining equipment, and state-of-the art inventory management systems.

Roland Anderson delivering the Laboratory Symposium presentation.

R. Anderson leads a discussion tailored to the applications employed by those in attendance.

Next, attendees were invited to help themselves to a complimentary hot buffet, featuring local Italian fare. Guests and staff carefully balanced plates, as they made way to their seats for the Laboratory Pumps and Applications presentation, delivered by KNF Laboratory Products Manager, and applications specialist, Roland Anderson (pictured right). The presentation featured a review of pump technologies, their pros/cons, and the benefits of their usage in several typical lab applications.

The evening was capped off with desserts and coffee, as well as a door prize drawing. Congratulations to the prize winners, and thank you to all who helped make this initial KNF Laboratory Pumps and Applications Symposium a success!

If you would like to schedule a similar KNF lunch-and-learn symposium with KNF, at your facility, please contact a laboratory applications specialist.

 

 

Flexibility is Key: The NFB Family of OEM Pumps Expands with Two New Low-Flow, Compact Models

NFB boxer-type liquid pumps

Full line of NFB boxer-type OEM liquid pumps

With the recent introduction of NFB 5 and NFB 25, this powerful, compact line of two-head-one-motor boxer pumps now boasts a wider flow rate range of 5 mL/min to 1.3 L/min per head.

This widened range offers further flexibility to the already gymnast-like abilities of this versatile line of products, such as:

 

  • The boxer configuration offers the flexibility of two possible operating modes.
    1) In parallel mode, the alternating pump head operation results in smooth, even flow.
    2) In individual mode, two liquids can be transferred simultaneously.
  • An adjustable-speed brushless DC motor adds flexibility, allowing simple flow rate regulation, which helps to reduce lengthy testing, while improving time to market.
  • Further instrument integration flexibility is assured by the small size, two-for-one design…
  • …and the ability of these pumps to operate in any orientation.
  • The two-for-one design and long product life also create cost savings potential.
  • Need more flexibility? Contact a KNF engineer to discuss your specific design needs.

OK, after reading about all of that flexibility, it’s probably time for a nice cool-down stretch! Then, click here to learn more about the flexible, expanded line of KNF NFB boxer pumps.

A widened range of boxer pumps offers further flexibility to the already gymnast-like abilities of this versatile product line.

A widened range of boxer pumps offers further flexibility to the already gymnast-like abilities of this versatile product line.

The Right Pump to Meet Your Continuous Ink-jet Printing Requirements

Application Note: OEMAs the continuous ink-jet (CIJ) printing industry evolves, KNF remains a driving force behind the change from yesterday’s peristaltic and gear driven pumps, to today’s more efficient diaphragm pumps. In fact, KNF is well positioned to serve this industry, thanks to our CIJ applications knowledge and selection of readily-optimized liquid and gas handling diaphragm pumps.

Diaphragm pumps overcome common problems inherent with the use of peristaltic and gear pumps in CIJ applications. Peristaltic pumps have short tube life leading to maintenance issues or messy clean-up, while gear pumps have issues including performance decay, shed particles, high cost, and they cannot run dry. In contrast, our diaphragm pumps provide a greatly extended performance life, lower cost operation, leak-tightness, robust chemical resistance, the ability to handle challenging inks, and our liquid pumps are self-priming and can run wet or dry. In addition, KNF diaphragm pumps can include features such as logic-controlled brushless DC motors, special electrical connections and mounting plates, and dampeners for applications sensitive to pulsation.

Air, Gas & Liquid Diaphragm Pumps for Continuous Ink-jet Printers

KNF Neuberger, Inc. specializes in liquid transfer pumps for continuous ink-jet printing industry. Specific media applications include UV ink pumps, pumps for solvent-based inks, degassing pumps, and many more.

Typical functions that our pumps perform in drop-on-demand inkjet applications include:

  • Bulk ink supply/replenish
  • Ink degassing
  • System vacuum and pressure
  • Cleaning station
  • Anti-siphon at head
  • Gutter pump
  • Chemistry make up
  • Ink delivery
  • Debris cleaning
  • QC analysis

KNF is also proud to have contributed to the CIJ market’s successful evolution to now include industrial printers and decorators, mailing and labeling equipment, date/lot codes, bio-material dispensing, 3-D printers, printed electronics, and more.

View the complete Application Note for more information, including a list of KNF pumps for continuous ink-jet printing and a more complete list of KNF pump features and benefits for CIJ applications.