CHO-SHRINK
®
1061
Military/Aerospace Conductive Heat
Shrinkable EMI Cable Shielding System
Tubing • Connector Boots • Cable Transitions • Boot Adapters
CHO-BOND
Adhesive/Sealant
CHO-SHRINK 90° Boot (Conductive Side)
CHO-BOND Adhesive/Sealant
CHO-SHRINK Tubing
(Conductive Inside)
Conductive Grommet
For Shield Grounding
CHO-SHRINK Continuity Splice (Conductive Outside)
Customer Value Proposition
CHO-SHRINK 1061 is an electrically conductive,
heat shrinkable material designed to provide
lightweight cable and connector EMI shielding.
CHO-SHRINK materials are ideal for any ap-
plications where weight savings associated with
EMI cable shielding is of paramount importance.
The product consists of polyolefin heat shrink-
able tubing, connector boots, and transition
pieces that are coated with Chomerics’ unique
silver filled coating system.
The CHO-SHRINK cable shielding system al-
lows for relatively easy assembly of shielding
systems for complex cable wiring harnesses
using conventional heat shrink tubing heating
devices. The system offers excellent shielding
and significant weight savings over traditional
metal braid cable shielding systems.
In addition, CHO-SHRINK offers an environ-
mental shield against dust, moisture and other
contaminants. CHO-SHRINK remains flexible to
support any needed cable routing. Easy repair
or rework of cables is facilitated by cutting off
the CHO-SHRINK material and installing new
material.
CHO-SHRINK materials are ideal for installa-
tion on cabling for medical device electronic
assemblies which require reliable EMI shield-
ing performance and may benefit from silver’s
antimicrobial properties.
Typical applications can include; missiles,
aircraft, satellites, vehicles, and on cables of any
other electronics systems where weight savings
is mandatory.
Product Features
•
Superior EMI shielding
•
Meets NASA outgassing specs for
space use
•
Excellent 360°
cable
shielding
effectiveness performance, 70 - 80 dB
attenuation above 500 MHz
•
Weight savings from 40 – 65% vs.
conventional braided mesh shielding
systems with labor savings as well
•
Easy installation and assembly with
conventional heat guns and ovens
•
Professional appearance
•
Excellent seal against moisture and
contaminants
•
Complex cable assembly EMI shielding
possible with a wide selection of cable
transitions, including T, Y, and other
custom shapes.
•
Standard (stocked) lengths for tubing
are 4 feet. For longer lengths, transition
tubing sections are available.
•
Unique coating system can be applied
internal or external to the heat
shrinkable tubing
•
CHO-SHRINK cable assemblies remain
flexible after installation
•
CHO-SHRINK connector boots provide
EMI shielding, cable shield grounding,
and strain relief at connector backshell
terminations.
•
CHO-SHRINK boots shrink to a wide
range of cable diameters (shrink ratio
is 4:1 at the cable end). They can be
supplied with a conductive hot melt
adhesive/sealant applied to each end.
•
Mil-R-46846 Polyolefin Tubing and Boots
Contact Information:
Parker Hannifin Corporation
Chomerics Division
77 Dragon Court
Woburn, MA 01801
phone 781 935 4850
fax 781 933 4318
chomailbox@parker.com
www.parker.com/chomerics
Application Instructions
•
For optimal shielding performance, be
•
To achieve a good mechanical grip
sure to terminate the shield at both ends
between CHO-SHRINK boots and
•
One of the major advantages of the
with full 360° contact to a low impedance
connector backshells, Chomerics strongly
CHO-SHRINK EMI cable shielding system
ground. Incorporate mechanical strain
recommends the use of Shrink Boot
over conventional metal shielding is its
relief into the cable design itself. That is,
Adapters, which provide a knurled and
ease of assembly. The following has
avoid stretching and bending the cable
grooved surface to enhance resistance
been prepared as a guide to the proper
excessively. Transition pieces should be
to torque, snap-off and pull-off stresses.
application and assembly of CHO-SHRINK
generous to preserve continuity at all
Tie-wraps should also be applied.
tubing, connector boots, and transitions.
junction points.
•
CHO-SHRINK molded parts are available
•
All CHO-SHRINK products may be
with a highly conductive hot-melt
recovered (shrunk) with the same heating
adhesive/sealant at each opening. This hot
equipment used on ordinary nonconductive
melt will flow during shrinking to provide
shrinkable plastics. Hot air blowers
an effective environmental seal without
and infrared heating devices provide the
degrading EMI shielding characteristics. If
simplest method of shrinking. Ovens
excess sealant flows outside the molded
may be used to recover tubing, but boots,
part during recovery, it can be easily wiped
transitions and other molded parts often
away while still warm.
require some hand positioning during
•
The only assembly procedure peculiar to
the shrinking process to assure correct
CHO-SHRINK is the necessity to maintain
alignment. Shrink temperatures should
electrical continuity through conductive
not exceed 375°F. Care should be taken to
inside surfaces from connector to
shrink the product slowly and uniformly.
connector. Where two CHO-SHRINK parts
Exceeding 375°F (191°C) may cause a loss
meet (boot/tubing, tubing/transition, etc.),
of shielding integrity.
a continuity splice must be achieved. This
is accomplished by using CHO-SHRINK
splice sleeves, which are short lengths
of CHO-SHRINK tubing with a conductive
outside surface.
2
CHO-SHRINK Assembly
Procedure
1.
Lay out entire cable, with all
branches in proper place.
6.
Slide CHO-SHRINK transitions into
2.
Slide CHO-SHRINK continuity
position, bending branches where
required to allow the expanded
transition to pass breakout
intersections. When properly
positioned, exposed continuity
splices should be entirely covered by
the transition.
9.
Terminate connector. Note: If
connector backshell does not
provide a knurled and grooved
surface for the CHO-SHRINK boot to
grasp, a Shrink Boot Adapter should
be installed on the backshell before
wires are terminated (see table of
Adapter sizes and part numbers).
splice sleeves (coating outside,
black inside) into position wherever
connector boots or transitions will
be shrunk against the cable.
7.
Apply heat to shrink transitions in
3.
Apply heat to shrink continuity
splices tightly against wire bundle.
4.
Slide pre-cut lengths of CHO-
place. During the shrinking process,
transitions can be positioned by
hand to assure correct alignment
and convenient breakout angles.
Ends of each transition should
be pressed down onto the splice
sleeve so that the conductive hot
melt adhesive around each opening
flows around splice to provide a
mechanical bond and seal. Note:
Do not handle cables after transition
shrinkage until cool.
10.
Slide CHO-SHRINK boot over
connector, and align so that boot
will shrink over threads of backshell
(or adapter) at one end and exposed
continuity splice at other end.
SHRINK tubing (inside-coated)
into position so that ends overlap
approximately one-half of each
continuity splice sleeve. When
determining cut-lengths, allow
for a maximum of 5% longitudinal
shrinkage.
11.
Apply heat and begin shrinking boot
at connector end first, using hands
to assure proper positioning. Press
boot tightly against backshell so
that conductive hot melt adhesive
provides mechanical bond and seal.
Continue shrinking boot, working
from connector towards cable. Press
“tail” end of boot down against
exposed splice so that conductive
hot melt bonds and seals.
8.
If CHO-SEAL conductive grommets
5.
Apply heat to shrink tubing against
wire bundle. Approximately ½ to 1
-1/2 inches of conductive surface
should be exposed at each continuity
splice.
are to be used to terminate
individual wire shields:
a. Strip outer jacket off each wire
and cut shield away leaving ¼” – 3/8”
of shield exposed.
b. Comb exposed shield back over
jacket.
c. Insert wires into grommet so
that exposed shields are securely
located in center of grommet.
3
Product Information
Typical Properties
Boot Material
Conductive Filler
Shore D Hardness
(ASTM D-676)
-55°C to 150°C (-67°F to 300°F)
200 V/mil
121°C (250°F) min. 191°C (375°F) max.
Operating Temperature Limits
Dielectric Strength* (ASTM D-876)
Shrink Temperature
Outgassing
(NASA Reference Publication 1124) (ASTM E595)
Total Mass Loss (TML) (%)
Collectible Volatile Condensable Materials (CVCM) (%)
Flammability (ASTM D-635)***
Shrink Ratio
Shielding Effectiveness (CHO-TM-TP12)
DC Resistance**
Shelf Life (from date of manufacture)
* Recovered base material
** After 100% recovery
*** Tested internally by Chomerics
0.67
0.04
UL VW-1
up to 4:1
See Figure 1
N/A
2 years
0.67
0.04
UL VW-1
up to 2:1
See Figure 1
0.5 ohm/foot
2 years
CHO-SHRINK
®
1061:
CHO-SHRINK Boots
Silver in polyolefin
50 ±10
CHO-SHRINK
®
1061:
CHO-SHRINK Tubing
Heat shrinkable polyolefin per MIL-R-46846 Type 5
-54°C to 135°C (-66°F to 275°F)
CHO-SHIELD
®
1061 Typical Shielding Effectiveness Per CHO-TM-TP12
120
100
Attenuation (dB)
80
60
40
20
0
10
100
Frequency (MHz)
1,000
10,000
Figure 1 Shielding Effectiveness for CHO-SHRINK 1061, 1/2” diameter tubing
4
Ordering Information
CHO-SHRINK
®
Tubing
Use the following part numbering system to order CHO-SHRINK tubing. Standard (stocked) lengths are 4 feet.
Ordering quantity should specify total length required. Part number indicates length of pieces.
Example: 70-21-0016-0004-10 = 4 feet of 1” diameter, with tubing coated on the inside cut to 10" lengths
70 - 2
-
- 0004 -
Cut lengths are in inches
For example:
10 = 10 inches
Expanded Inside Diameter Code
Enter inside diameter in 1/16ths
For example:
0004 = 1/4” ID
0008 = 1/2” ID
0016 = 1” ID
Coating Configuration
1 = Coated inside
2 = Coated outside
3 - Coated inside & outside
Available Standard Diameters and Wall Thicknesses
Expanded
Inside Dia.
Inches (mm)
1
3
Expanded
Inside Dia.
Code
0002
0003
0004
0006
0008
0012
0016
Typical Recovered
Wall Thickness
Inches (mm)
0.020 (0.51)
0.020 (0.51)
0.025 (0.63)
0.025 (0.63)
0.025 (0.63)
0.030 (0.76)
0.035 (0.89)
/
8
(3.18)
/
16
(4.76)
/
8
(9.53)
¼ (6.35)
3
½ (12.7)
¾ (19.05)
1 (25.4)
For non-standard sizes, contact Chomerics.
5