Extensive information is available regarding polymers utilized in industrial hoses. However, appropriate selection methodologies for choosing the safest and most effective couplings are rarely discussed. Hose leaks, failures and worker safety issues can be avoided by understanding how to select the best coupling for your hose assembly.
Watch this webinar to learn:
• How materials and application impact coupling selection
• The importance of choosing the appropriate attachments, coupling construction, size and thread
• Considerations in regards to ease of handling, quality and more
2. Before We Start
q This webinar will be available afterwards at
designworldonline.com & email
q Q&A at the end of the presentation
q Hashtag for this webinar: #DWwebinar
8. Carbon & Alloy Steel Couplings
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Applicable in low to high pressure environments
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Different types of carbon steel are suitable for different
applications
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Carbon steel can be customized for specific applications
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Carbon content determines the ultimate strength,
toughness, ductility, machinability, weldability, and
corrosion resistance
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A great option when rust is a concern
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More commonly available, utilizes standard tooling,
relatively inexpensive
9. Brass Couplings
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Applicable in low pressure environments
and some (not all) fuel lines
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Allows for banding or clamping with no
metal to metal contact
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Important not to attach by crimping as
the metal is too soft
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Moderate prices
10. Aluminum Couplings
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Used in marine, agriculture, and mobile
technologies
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Weighs less than brass or steel, great for
reducing weight in assemblies
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Good corrosion resistance, ductility, and
strength
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Moderate prices
11. Stainless Steel Couplings
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Good for corrosive environments such as
salt water and maritime applications
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Applicable in low to extremely high
pressure environments
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Many grades of stainless steel are
available but major coupling
manufacturers use 316
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Can be significantly more expensive than
standard carbon steel so should only be
used when situation dictates
12. Attachments
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Options include ferrules or band/clamp attachments
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Ferrules
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Ø
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Band or clamp attachments
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For most hoses over 150 PSI or for various media
Available in metal or brass
For low pressure applications such as material transfer
More information
Ø
See: http://www3.catalogds.com/ecrimp/ or hose and
coupling manufacturer information published in catalog
and crimp data database
13. Construction
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Must be compatible with fluid going through the hose
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Coupling stem must be compatible with the hose
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If the serrations or bead on the stem are not correct, they
damage the hose and leak, or the coupling will come off
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Options include spiral, wire braid, textile, or helical reinforced
construction
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Spiral is for high impulse and high pressure applications
Wire braid is for high pressure, moderate impulse applications
Textile reinforced is for moderate impulse, fairly high pressure,
and lightweight or non-conductive needs
Helical is for suction applications to prevent hose collapse
14. Size & Terminations
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Size is determined by the volume of fluid that will move through
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If not sized correctly, the fluid will either increase
in velocity or slow down and not transfer quickly enough
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Termination will be determined by the components
the hose connects to
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Determine best coupling size utilizing a Pressure Drop Calculator
or Gates hydraulic hose and coupling catalog on page 64
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Appropriate thread is dictated by SAE or ISO standards
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Find hose and coupling descriptions, pressure ratings, thread configurations, and
additional information in SAE J516, 517, 518, and J343 cover tests
15. Coupling Compatibility
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Compatibility is determined by the manufacturer
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Coupling has to be compatible with the hose, the
fluid going through the hose, and the external
environment
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Termination (sealing design) must match
component and pressure rating
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Must consider fluid or media going through the hose
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Coupling/hose including sealing surface MUST meet pressure and velocity
requirements
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External or ambient conditions that may corrode prematurely should be considered
16. Quality
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Cheap couplings may have poor plating that will
rust, or they may not be consistently compatible
with the hose they are attached to and come off
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Good quality fittings can be counted on to work
every time without worry
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Quality will vary dramatically between
manufacturers
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Some products barely meet SAE minimums;
others go 3X SAE standards
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Design specifications are published in catalogs
or on the hose layline
17. Ease of Handling
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If attaching and detaching the coupling frequently, use
camlock or other easy-to-use couplings
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A threaded or bolt on connection is recommended if the
connection is to remain attached for longer periods of time
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Questions to ask in ease of handling include:
Ø What are you putting through the hose?
Ø What volume do you need to flow? (Volume and
pressure determine velocity.)
Ø What pressure is needed? (Different couplings may be easy to hook up, but won’t
handle pressure or fluids.)
Ø What type of port are you connecting to?
Ø What type of connection will be best and easiest – bolt on clamps that can be
done in the field, flange, hammer union/API, camlock, etc.?
18. Considerations in Ease of Handling
Force
to
bend
Bend
radius
Weight,
abrasion
resistance
Cover
fric7on
coefficient
Crimp
(skive,
or
no
skive)
Diameter
Hybrid
hoses
for
mul7ple
hoses
Weight
Flexibility
19. Exposure
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Must consider internal and external exposure
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Considerations in exposure include:
Ø Human exposure
Ø External exposure
Ø Hazardous exposure
Ø Any environmental and fluid interactions
Ø Temperature & pressure
Ø Impulse frequency
Ø Amplitude and wave form
Ø Vibration
Ø The connection’s risk in the system
Ø Installation
Ø Reliability
22. Thank You
q This webinar will be available at designworldonline.com & email
q Tweet with hashtag #DWwebinar
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