5
PerformanceUnder Pressure
Although Parker’s Instrument tube fittings have been engineered
and manufactured to consistently provide this level of reliability,
no systems integrity is complete without considering the critical link,
tubing
Whilst it is the responsibility of the
system designer/user to ensure the
correct specification of materials and
tube to ensure system integrity, this
brochure is intended as a guide to assist
the designer in properly selecting and
ordering quality tubing and details the
compatibility of selected tubing with
Parker fittings.
Correct tube selection and installation,
we believe, are key ingredients in
building leak-free reliable tubing
systems.
The following parameters should be
considered when designing a leak-free
system and ordering tubing for use with
Parker tube fittings:
•
Tubing Hardness
•
Tubing Wall Thickness
•
Tubing Surface Finish
•
Material Compatibility
Tubing Hardness:
Remember
Parker Instrumentation Tube Fittings
are designed to work within specific
hardness ranges. Fittings are
designed so the differential hardness
between tube and fitting are optimum
for a reliable and trouble-free
operation.
Tube Wall Thickness:
Proper
wall thickness is necessary to
accommodate accepted safety
factors relative to desired working
pressures.
Tube Surface Finish:
As best
practice, it is fundamental to control
the tubing finish and straightness.
Always select tubing free of visible
draw marks or surface scratches.
If possible, cut off any undesirable
sections. These ‘deep’ scratches
can cause leaks when attempting
to seal low-density gases such
as argon, nitrogen, or helium. In
addition, tubing shall be reasonably
straight and ends must be smooth
and free of burrs or any other
imperfections.
6
Mo
Imperial
Tube
O.D.
Size
Wall Thickness, inches
0.02 0.028 0.035 0.049 0.065 0.083 0.095
1/16
1/8
7100 10500
3/16
6700 8600
1/4
4900 6300
5/16
4900 7100
3/8
4000 5800 8000
1/2
3200 4600 6200
5/8
3600 4900
3/4
3000 4000 5200
7/8
2500 3400 4400
1
2900 3800 4400
6
Mo
Metric
Tube
O.D.
Size
Wall Thickness, mm
0.8 1 1.2 1.5 1.8 2 2.2 2.5
3
550
6
410 520
8
380 470
10
300 370 470
12
250 300 380 470
14
270 340 420
15
250 320 390
16
230 300 360
18
210 260 320 360
20
180 230 290 320
22
210 260 290 320
25
220 250 280 320
Tubing Specification: High Quality, Fully Annealed, Super Stainless Steel Tubing to ASTM A269/A213 Grade UNS S31254.
Recommended Tube Hardness 80 HRB. Maximum Permissible Hardness 90 HRB.
Not recommended for gas service
Recommended for all services - standard assembly
Recommended for all services - Use pre-assembly tool
Recommended for all services - Use ‘Hyferset’ pre-assembly tool
No data/Not recommended/No solution
Working pressure is measured in ‘bar’
Working pressure is measured in ‘psig’