Chemical Engineering October 2020 - 17

pared to traditional seals, correlating
with field tests and predictions from
finite-element analysis (FEA). Noncontacting
labyrinth seals reduce
leakage in centrifugal applications.
This is accomplished by restricting
flow through a series of chambers
formed between the rotating
element while the teeth control the
passage of the media. The improved
performance is said to be due to
the innovative combination of custom-engineered
tooth designs and
high-performance PEEK (polyether
ether ketone) thermoplastic materials.
The materials reduce friction and
eliminate galling, which extends the
seal's life and lowers maintenance
costs. The erosion and corrosion resistance
make the Arlon 4020 suitable
for severe sealing applications.
- Greene Tweed, Landsdale, Pa.
www.gtweed.com
Conductive sealing materials
for dynamic applications
Launched last year, Turcon MC1 and
Turcon MC2 materials are said to
be the only polytetrafluoroethylene
(PTFE) based electrically conductive
materials suited for use in spring
and elastomer-energized seals. " Engineered
for dynamic applications,
seals and bearings from the materials
will provide reliable electric connection
between moving parts, " says
Soeren Roepstorff, development
manager at the company's manufacturing
facility in Helsingør, Denmark,
where the new compounds were
developed. " Conductive elastomers
are available, but these are primarily
only for static applications, while
the conductive, injection-moldable
plastic materials that exist have low
flexibility and are less suited for sealing
purposes and for installation in
closed grooves, " he says. Electric
charge transfer through the gap between
two components can cause
sparks or stray current in machinery
and systems, for example in electric
motors. This can result in hardware
pitting and carbonization of lubricant
or grease. Use of an electrically
conductive seal or bearing grounds
the system by creating a clear path
between two components, avoiding
corrosion issues. Turcon MC1
(photo, left) is a medium-filled material
for dynamic applications requiring
medium to high conductivity,
while Turcon MC2 (photo, right) is a
high-filled material for dynamic applications
requiring high conductivity.
- Trelleborg Sealing Solutions
Americas, Schaumburg, Ill.
www.tss.trelleborg.com/en
This new sealing technology
enhances pump performance
New developments of an innovative
sealing technology have been added
to the range of Viking Universal
Seal Series of Internal Gear Pumps
(photo). The result is a more costeffective
sealing option compared
to traditional mechanical seals, while
also reducing leakage rates compared
to using pumps with packing.
The new option is also designed for
back pull-out, which helps to reduce
downtime and simplify maintenance.
Available from this company, the new
O-Pro seal uses a series of O-rings to
create a robust seal and lubrication
chamber in a single-piece seal. This
new feature can be fitted throughout
the Viking Universal Seal Series
pumps, which cover flows to 295
m³/h, discharge pressures to 14 bars
and liquid viscosities of 20-1,700
cSt at temperatures between -15 to
175°C. - Michael Smith Engineers
Ltd., Woking, U.K.
michael-smith-engineers.co.uk
Chevron seals for
flow-wrapping packaging
Flow-wrapping is one of the most costeffective
methods for packaging highprofile
products. However, in medical
device applications, it is more commonly
applied to products where the
product sterility of the outside of the
product is not essential. This company
is introducing chevron seals (photo)
with peelable side seals, which dramatically
improves ease of opening,
making cost-effective flow-wrapping
a feasible alternative for dimensional,
larger, or bulky disposable products
that require a strong, but easy-to-open
seal. Chevron sealing is ideally suited to
such products, as they can challenge
seal integrity on all four package sides.
This capability is particularly important
given recently updated ISO 11607
guidelines that emphasize point-ofuse
aseptic presentation of terminally
sterilized medical devices. - HarpakULMA,
Taunton, Mass.
www.harpak-ulma.com
■
Gerald Ondrey
CHEMICAL ENGINEERING WWW.CHEMENGONLINE.COM OCTOBER 2020
17
Greene Tweed
Trelleborg Sealing Solutions Americas
Michael Smith Engineers
Harpak-ULMA
http://www.tss.trelleborg.com/en http://www.gtweed.com http://michael-smith-engineers.co.uk http://www.harpak-ulma.com http://WWW.CHEMENGONLINE.COM
Chemical Engineering October 2020

Table of Contents for the Digital Edition of Chemical Engineering October 2020
