Transcript Kimray Distributor Presentation

Parker O-ring
Division
The High
Performance
Leader
Material
Technology
The Chemistry of
Elastomers
Rubber Technology
 “Rubber” compounds are resilient (elastic)
materials made from one or more crosslinked base polymers, reinforcing agents,
processing aids, and performanceenhancing additives. Compounds are
tweaked for performance variations by
adding other ingredients to the base
polymer.
Polymers – Basic Information
 Base polymer determines chemical resistance,
rough temperature limits, and rebound
resilience. Also provides “baseline” for
abrasion resistance, compression set
resistance, permeability.
 Polymer chains must be “glued” together
(cross-linked) to achieve resilience and
elasticity. Typical curing systems are Sulfur,
Organic Peroxides, and Bisphenol.
Compounding - Fillers
 Fillers are reinforcing agents that add
mechanical strength and resistance to
abrasion, permeation, and compression set
 Carbon black: standard for black compounds
 Silica: standard for non-black compounds
 Pasticizers are oils and/or polymers used to
lower the low temp limit of Nitrile and make
the material flow better
O-ring materials used at Kimray
 Nitrile (NBR) Buna
 Fluorocarbon (FKM)
®
Viton
 Hydrogenated
Nitrile (HNBR) HSN  TetrafluoroethylenePropylene (TFE/P)
 Ethylene-Propylene
®
Aflas
(EPR, EP, EPDM)
 Polyurethane (AU,  Perfluoroelastomer
®,
(FFKM)
Kalrez
EU)
Chemraz®, Parofluor®
Standard
Materials
Fluorocarbon (FKM) VITON®
-15° F to + 400° F V1164-75
 Recommended For  Not Recommended
 Petroleum oils
For
 Silicone fluids
 Ketones
 Acids (Black ONLY)
 Steam and hot
 Aromatic solvents
 Halogenated

hydrocarbons
 Air



water
Amines
Low temperature
Automotive brake
fluid
Aircraft brake fluid
Nitrile (NBR) Buna
-40° F to 250° F
N0674-70
 Recommended for:
 Aliphatic hydrocarbons
(propane, butane, petroleum
oil, mineral oil and grease,
diesel fuel, fuel oils)
vegetable and mineral oils
and greases.
 Dilute acids, alkali and salt
solutions at low
temperatures.
 Water (special compounds
up to 100°C) (212°F).
 Not recommended for:
 Fuels of high aromatic
content (for flex fuels a
special compound must be
used).
 Aromatic hydrocarbons
(benzene).
 Chlorinated hydrocarbons
(trichlorethylene).
 Polar solvents (ketone,
acetone, acetic acid,
ethyleneester).
 Strong acids.
 Brake fluid with glycol base.
 Ozone, weather and
atmospheric aging.
Hydrogenated Nitriles (HSN, HNBR)
-25° F to 300/325° F
 Recommended for:








Well service
Improved methanol and
sour gas resistance over
nitrile
High temperature
resistance relative to
Nitrile
Petroleum oils
Water/Steam
Dilute acids and bases
Aliphatic hydrocarbons
Ozone
 Not recommended for:






Polar solvents (methanol
and ketones)
Strong acids
Fuels
Chlorinated hydrocarbons
Acetone
Aldehydes
N4007-95, KB163-90, N1231-80, N1173-70
Special
Materials
Ethylene
Propylene
(EPDM, EP, EPR)
Ethylene –Propylene (EPDM, EPR)
-60° F to + 250°
 Recommended for
 Geothermal
 Steam service
(500°F)
 Explosive
decompression
 Steam/oil mixtures
of less than 10%
petroleum fluid
E0962-90
 Not Recommended
for
 Mineral oil products
E0962-90 is unique in that is
can withstand continous
steam applications at 500°F
Highly
Saturated
Nitrile
(HSN, HNBR)
Low Temperature HNBR
-58° F to + 300° F
KA183-85
 Wide temperature range:
 Excellent abrasion resistance
 Excellent wear resistance
 Good extrusion resistance
 Extensive testing profile for EOG-specific
requirements which include testing in:
 Methanol
 Oil
 Marston Bentley’s oceanic fluids
 Kerosene
 Baroid’s Petrofree drilling fluid
Fluorocarbon
(FKM)
Low Temp Fluorocarbon(FKM)
-55° F to + 400° F V1289-75
V1289-75 has significant advantages compared
with other elastomeric seal materials:
 Compared to GLT FKM:
 Better low temperature rating
than GLT FKM
 Lower volume swell than than
GLT FKM
 Compared to GFLT FKM:
 Better low temperature rating
than GFLT FKM
 Better compression set than
GFLT FKM
 Compared to standard FKM
 Better low temperature rating
than standard FKM
 Lower volume swell than
standard FKM
 Compared to low temperature
Nitrile
 Better compression set than
Nitrile
 Lower swell than Nitrile
 No dry-out shrinkage
 Better high temperature rating
than Nitrile
Sour Gas Service FKM
+10° F to + 400° F
VP104-85 has significant
advantages for the Energy, Oil
and Gas industry compared with
other elastomeric seal materials
 Compared to standard A-type
FKM
 Better explosive decompression




resistance in sour gas
Better amine resistance
Better base resistance
Better methanol resistance
Better steam / hot water
resistance
 Compared to FFKM
 Better explosive decompression
resistance in sour gas
 Lower cost
VP104-85
 Compared to HNBR
 Better ED resistance
 Better steam/hot water
resistance
 Better acid/base resistance
 Better high temperature
performance
 Compared to high-
temperature HNBR
 Better explosive
decompression resistance
in sour gas
 Better steam/hot water
resistance
 Better acid/base resistance
 Better high temperature
performance
ETP Fluorocarbon (FKM)
-15° F to + 400° F
V1260-75
 Increased Chemical  Not Recommended
Compatibility
For
 Practically
 Refrigerant gases
everything
 Polar and Aromatic
solvents
 Low cost
applications
 Low temperatures
Polymer trade name is Viton® Extreme –
similar performance to Hifluor®, but usually a
lot less expensive.
Explossive Decompression Resistant
15°F to +400°FFKM V1238-95
 95 Shore A Durometer Fluorocarbon.
 Developed for maximum extrusion
resistance, good compression set
resistance.
 ED Resistant
 Applications: High temperature, highpressure H2S.
FFKM
HIFLUOR ®
TFE/P
Specialty
Compounds
Parofluor ULTRA(FFKM)
+5° F to + 600° F
 Recommended For  Not Recommended
 Down hole (sour




gas)
Drilling mud
Amine-based fluids
Steam and other
aggressive fluids
High temperature
applications
FF200-75 FF500-75 FF202-90
For
 Refrigerant gases
 Low cost
applications
 Low temperatures
Competes directly with
Kalrez ® and Chemraz. ®
The best of the best.
FFKM
Chemical Resistance Properties
Chemical Family
FF500-75
FF200-75
Kalrez® 4079
Organic Acids
1
1
1
Inorganic Acids
1
1
1
Bases
1
2
3
Amines
1
3
4
Steam/ Hot Water
1
2
3
Ketones
1
1
1
Aldehydes
1
2
4
Hifluor ® (FKM)
-15° F to + 400° F
 Recommended For
 Not Recommended For
 Down hole (sour gas)
 Refrigerant gases
 Drilling mud
 Low cost applications
 Amine-based fluids
 Low temperatures
 Steam and other
aggressive fluids
V3819-75
V8534-90
Similar chemical properties
as Parofluor but about 20%
less expensive.
Aflas® (TFE/P)
+15° F to + 450° F
 Recommended For
 Petroleum oils
 Alcohols
 Silicone fluids
 Sour gas
 Amines
 Air
 Steam / hot water
 Not Recommended For
 Low temperature
 Gasoline
Poor compression set –
primarily used in
chemical plants.
V1041-80 VP101-80 VP103-90
Explosive
Decompression
Materials
Explosive Decompression
Resistant Compounds
 N1231-80 (HNBR)
 E0962-90 (EPDM) VP103-90 (Aflas®) V1238-95 (FKM, Viton®) V8534-90 (HiFluor®) V8588-90 (Parofluor®, FFKM, Kalrez®) FF202-90 (Parofluor Ultra®, FFKM, Kalrez®)-
Failure
Modes
Maximizing life
through failure
diagnosis
Common reasons for O-Ring failure
(Often an O-Ring fails from a combination of problems)
 Abrasion
 Chemical attack
 Compression set
 Cracks in Nitrile rubber
 Exceeding material temperature limits
 Explosive Decompression
 Extrusion and/or nibbling
 Installation Damage
 Overfill
 Spiral failure
Abrasion
 Looks like the seal is sanded off or
flattened on one side of the o-ring.
 Causes:
 Poor surface finish
 O-Ring passes over ports
 Use of non abrasion resistant material
 Excessive swell and softening
 No lubrication
Abrasion
 Solutions:
 Check finish and smooth if necessary
 Use a lubricant or internally lubricated material
 Use a material that resists wear
 Use a lower swell material
Chemical Attack
 The seal swells a lot, shrinks, loses
physical properties.
 Excessive swell, brittleness, and
dramatic loss in physical properties. Find
a compatible base polymer.
 Shrinkage: the fluid is probably
extracting something from the rubber.
Chemical Attack
Chemical Attack
 Solutions:
 Use material compatible with all
fluids. Determine percentage of all
fluids in the stream.
 Find a compatible base polymer.
Determine compound by chemical
analysis and reviewing MSDS.
 Change compounds (changing the
base polymer isn’t always required.)
Compression Set
 O-Ring Conforms to shape of
groove
 Looks like the seal has been
flattened or deformed.
 Causes:
 Happens whenever rubber is
compressed -- is accelerated by:
o excessive or insufficient squeeze
o high temperatures
o Chemical attack due to
incompatible fluids.
Compression Set
HC HR HI
Compression Set = amount of loss / initial deformation
Compression Set = (HI – HR)/ (HI – HC)
Compression Set = (.100 - .090) / (.100 - .075)
Compression Set = (.010) / (.025 ) = .40
Compression Set = 40%
Compression Set
Compression Set
 Solutions:
 Evaluate gland dimensions
o check for proper squeeze
o consider tolerances
o consider ID stretch and cross section reduction
 Evaluate material
o check for compatibility with fluids and temperature
o use set resistant compound
Cracks in Nitrile Rubber
 Evenly spaced radial cracking around
the circumference of the O-Ring
(typically Nitrile) -- especially where it’s
stretched.
 Causes:
 Ozone, UV light, Fluorescent light, Electric
motors. There is ozone in the air around
us, and this can be enough to destroy an
O-Ring.
Cracks in Nitrile Rubber
Cracks in Nitrile Rubber
Cracks in Nitrile Rubber
 Solutions:
 Coat o-rings with a silicone or petroleum
lubricant
 Choose a base polymer that is naturally
resistant to ozone
Low Temperature Failure
 Seal leaks at low temperatures only.
 As seal materials cool to within 15oF of their
minimum operating temperature, they lose
resilience. Any movement may allow leakage of
low viscosity liquids and gases. Low temperature
changes are not permanent and do not damage the
seal.
 Use a seal material with improved low temperature
performance.
High Temperature Failure
 Rubber “melts” or becomes brittle.
 Every rubber polymer has a temperature above
which it begins to break down. Thermal
degradation is permanent and irreversible.
 Use a seal material with improved high
temperature performance or cool the seal gland
area.
Explosive Decompression
 Internal or external cracks, ruptures,
blisters.
 Causes
 Gasses permeate material and when
system is rapidly decompressed, gas
quickly escapes leaving ruptures
Explosive Decompression
Explosive Decompression
 Solutions:
 Slice cross section at blister or rupture
and look for internal fissure to verify
explosive decompression is cause
 Determine application pressure and
decompression rate
 Slow decompression rate
 Use explosive decompression resistant
material
 Use a more explosive decompression
resistant material such as V1238-95.
Extrusion and Nibbling
 Looks like one side of the seal is
chewed off.
 Is caused by high pressure “pushing”
the O-Ring into a gap between the
metal surfaces.
 Causes.
 High pressure
 Excessive clearance
 Excessive swelling and softening
Extrusion and Nibbling
Extrusion and Nibbling
Extrusion and Nibbling
Extrusion and Nibbling
Extrusion and Nibbling
 Solutions
 Evaluate gland design
o Use InPHorm or extrusion chart to
determine pressure rating
o If gland can be widened, use backup
ring
 Evaluate material
o Use higher pressure material
o Use material compatible with the
environment
o Use extrusion resistant compound if
necessary
Installation Damage
 Sheared, torn, nicked cut appearance
 Causes:
 sliding over threads
 insufficient chamfer
 improper size
 no lubrication
Installation Damage
Installation Damage
 Solutions:
 cover threads during installation
 use lubrication
 chamfer and smooth edges
 use correct size
Overfill
 Appears similar to extrusion, but nibbling
is on both sides, or O-Ring takes set with
visible ridge over groove edge.
 Causes
 Insufficient void space in groove
 Excessive swell in system fluids
 Improper size O-Ring
Overfill
 Solutions:
 Use proper groove width
 Use lower swell material
 Use smaller cross section if squeeze is
not reduced below recommended
minimum
Spiral Failure
 Looks like a split wrapping around the
ring.
 Causes:
 Happens when the seal on a piston or
rod “grips” instead of slides in one spot
(common with long, slow strokes).
 Can happen on static seals with pressure
cycling.
 ID to CS aspect ratio, reciprocating
 Installation damage
 Soft material
 No lubrication
Spiral Failure
Spiral Failure
 Solutions:
 Can be prevented by using a smoother
surface, lubricating uniformly, using a stiffer
rubber compound, or using an engineered
seal.
 Use proper cross section for inside diameter
to provide stability in groove for
reciprocating seal
 Use a lubricant or internally lubricated
material
 evaluate surface finish, chamfer, sharp
edges
 Use different cross section shape to provide
stability in groove
Questions