Garlock GYLON EPIX®
The next generation in PTFE gasketing

Leaders in Sealing Integrity

GYLON EPIX® | The Next Generation of PTFE Gasketing
GASKETING CHALLENGESWHY GASKETS FAIL
GYLON EPIX® is a patented family of PTFE gaskets designed to solve many of the industry’s most common gasketing challenges,
such as poor load retention, old worn flanges or equipment that was not designed with the gasket joint in mind.

IMPROPER BOLT LOAD SOLVED
Non-metallic (FRP) flanges provide a costeffective piping option for chemical services.
However the low allowable torque is anissue when process media eliminates rubber(elastomeric) gaskets as an option, and PTFE
is required.

POOR FLANGE CONDITIONS ADDRESSEDReplacing or repairing worn, damaged or
misaligned flanges can result in costly
downtime. A sealing solution that can workin less-than-perfect flanges would solve thisproblem.

PERFECT FOR AGGRESSIVE & CORROSIVE MEDIA
End-users are often frustrated bygaskets that leak, particularly when they
are responsible for containing aggressive
and corrosive chemicals throughout theplant.

GASKET SELECTION SIMPLIFIED
Having more than one thickness resultsin more inventory, as well as confusion
when it comes time for an operator toselect a gasket. One thickness thatcovers all sizes is beneficial.

Leaders in Sealing Integrity
2

GYLON EPIX® | The Next Generation of PTFE Gasketing
INTRODUCING GYLON EPIX®
The perfect solution for imperfect flanges

A BETTER SOLUTIONGYLON EPIX® is a family of gaskets that effectively seals a broader range of applications and is more forgiving during theinstallation process. GYLON EPIX® allows the end user to save valuable turn-around time, reduce re-work, and lower costs,
helping them to finish ahead of schedule and under budget.

IMPROPER BOLT LOAD SOLVEDENGINEERED SURFACE PROFILE» Helps achieve a seal in poor flange conditions» Engineered surface profiles concentrateload resulting in stress optimization» Testing shows effective sealing in flanges
with .010” and .020” deep scoring

POOR FLANGE CONDITIONS ADDRESSEDEXCELLENT SEALABILITY» Helps to mitigate the effects of improperbolt load» Up to 10x more compressibility thantraditional PTFE gaskets» Effectively seals liquids at stresses as low
as 300-600 psi» Suitable for FRP flange applications

PERFECT FOR AGGRESSIVE & CORROSIVE MEDIA
TRUSTED MATERIALS» Made from traditional GYLON® PTFE which
eliminates the need for most customers tore-qualify» Chemical resistant, proven with aggressive
and corrosive media» Available in sheet and discreet forms andcan be dovetailed

GASKET SELECTION SIMPLIFIEDUNIVERSAL THICKNESS» Helps avoid improper gasket selection» Offered in one thickness - 3/32” (2.4mm)
that provides the conformability of thicker
1/8” (3.2mm) gaskets, and the improved
blowout resistance, load retention andsealability of 1/16” (1.6mm) thick gaskets

Leaders in Sealing Integrity
3

GYLON EPIX® | The Next Generation of PTFE Gasketing
The GYLON EPIX® Difference
GYLON EPIX® provides superior functional performance by combining the traditional attributes of GYLON® with an innovative
surface design. It offers broader applicability in worn and pitted flanges than traditional PTFE. In addition, GYLON EPIX® delivers thesealing and load retention properties of 1/16” and the conformability of 1/8”.The hexagonal profile provides improved compressibility
and recovery. The profiled surface reduces the contact area during initial compression to concentrate the compressive force ofthe flange for improved sealability.
LOAD RETENTION & CONCENTRATED GASKET STRESSGYLON EPIX® is able to distribute the load more evenly and prevent areas of low loading.

GYLON EPIX®

Traditional GYLON®

While the traditional gasket saw areas of lower stress (white and light red areas), the hexagonal pattern in GYLON EPIX®
concentrated the stress more evenly across the entire gasket.

TYPICAL ASSEMBLY STRESS RANGE RECOMMENDED FOR COMMON GASKET TYPESGYLON EPIX®

Compressed Fiber Gasket

PTFECorkRubberMoldedGasket
01000

2000

3000

4000

5000

6000

7000

8000

9000

10,00011,00012,00013,00014,00015,00016,000Assembly stress (PSI)

Leaders in Sealing Integrity
4

GYLON EPIX® | The Next Generation of PTFE Gasketing
GYLON EPIX® Styles
GYLON EPIX® STYLE 3500
Silica filled PTFEAPPLICATIONS» Strong Acids» Solvents» Hydrocarbons» Water» Steam» Chlorine» Cryogenics

GYLON EPIX® STYLE 3504
Aluminosilicate Microsphere filled PTFEAPPLICATIONS» Most acids and somecaustics» Hydrocarbons» Solvents» Water» Refrigerants» Cryogenics

GYLON EPIX® STYLE 3510
Barium Sulfate filled PTFEAPPLICATIONS» Strong caustics» Moderate acids» Chlorine» Gases» Monomers» Steam» Hydrocarbons» Cryogenics» Aluminum fluoride

Leaders in Sealing Integrity
5

GYLON EPIX® | The Next Generation of PTFE Gasketing
CASE STUDIESCHEMICAL
Chloralkali & Chlorine Processor
BACKGROUNDOPERATING CONDITIONSThis plant site has both flat face FRP and lap joint nickel pipe
flanges. Overtightening and rupturing of their gaskets wasa common issue, while alternate solutions were generally
unreliable in FRP flanges due to low bolt torque allowed. The
customer needed to consolidate to the fewest number ofgaskets that would be suitable for chloralkali process media,
metal lap joint flanges and FRP flanges. The customer also
desired a gasketing option that was available in sheet form,
to give them the flexibility to produce any size and shapegasket.

Temperature: 194°F (90°C) - 203°F (95°C)
Application: Raised face lap joint nickel and flat face FRP flanges
Media: Potassium hydroxide and catholite
Pressure: 50 - 70 psig (3.4 - 4.8 bar-g)
Size: 6” ring and full face gaskets
SOLUTIONGYLON EPIX® Style 3510

MINING
Copper Refining
BACKGROUNDOPERATING CONDITIONS

The gas shut off globe valve flanges were a chronic sourceof leakage. Not only were the flanges 8”-150# flat face,which are notorious for having marginal bolt loading, but thefaces were also worn and damaged due to age. These twoissues made it difficult for the customer to achieve a tightreliable seal with the PTFE and utility grade compressed
fiber gasket materials historically used at the facility.

Temperature: Ambient
Application: 8”-150# flat face flanges - globe valve in main gas
feed line
Media: Natural gas
Pressure: 60 psig (4.1 bar-g)
SOLUTIONGYLON EPIX® Style 3500

Leaders in Sealing Integrity
6

GYLON EPIX® | The Next Generation of PTFE Gasketing
CASE STUDIESFOOD PROCESSING
Food & Beverage
BACKGROUNDOPERATING CONDITIONS

The customer’s chemical treatment vessel had nonstandard
rectangular flanges with a limited number of bolts. Thelimited bolting resulted in inadequate compression to seal
the gasket and the non-standard shape made the use ofa molded engineered gasket unfeasible. Previously thecustomer was using expanded PTFE, which leaked from thetime it was first installed but, because they were unable tofind a better alternative, they simply accepted the leakage.

Temperature: 86°F (30°C) - 104°F (40°C)
Application: Custom rectangular flange
Media: Dilute caustic soda
Pressure: 50 psig (3.4 bar-g)
SOLUTIONGYLON EPIX® Style 3504

PULP & PAPER
Paper Board/Packaging
BACKGROUNDOPERATING CONDITIONS

The two main media used at this paper board and paper
packaging plant are white liquor and wash stock. The 8”150# stainless steel ball valve used in caustic liquor service
and the 24”-150# stainless steel gate valve in the wash
stock were both a source of chronic leaks. The customer
had attempted several times unsuccessfully to seal thevalve flange connections with metal inserted PTFE, e-PTFE
tape and EPDM rubber. The attempts were not only costly indowntime, but also created several safety and housekeeping
issues for the facility.

Temperature: 100°F (37°C) - 115°F (46°C)
Application: Stainless steel valve flange
Media: Caustic white liquor & wash stock
Pressure: 85 psig (5.9 bar-g)
SOLUTIONGYLON EPIX® Style 3510

Leaders in Sealing Integrity
7

GYLON EPIX® | The Next Generation of PTFE Gasketing
TECHNICAL DATAGENERAL SEALING CHARACTERISTICS
Style 3500 EPX
Fawn

Color
Composition

Style 3504 EPX
Blue
PTFE w/ aluminosilicate
microspheres

PTFE w/ silica

Temperature range
Minimum:
Operating:
Maximum:
Pressure
Operating:
Maximum:
PxT, max. - psig x ˚F (bar-g x ˚C)

Style 3510 EPX
Off-WhitePTFE w/ barium sulfate-450°F (-268°C)
400°F (204°C)
500°F (260°C)-450°F (-268°C)
400°F (204°C)
500°F (260°C)-450°F (-268°C)
400°F (204°C)
500°F (260°C)

750 psig (52 bar-g)
1200 psig (83 bar-g)

750 psig (52 bar-g)
1200 psig (83 bar-g)

750 psig (52 bar-g)
1200 psig (83 bar-g)

350,000(12,000)

350,000(12,000)

350,000(12,000)

47

52

43

>17>25>182,000(14)2,000(14)

2,000
(14)

3/32”
(2.4mm)Compressibility Range(ASTM F36) %Recovery(ASTM F36) %Tensile Strength psi(ASTM D1708)(N/mm2)Bacterial GrowthWill not support

GYLON EPIX® APPROVALS & CERTIFICATIONS
Style 3500 EPX

Style 3504 EPX

Style 3510 EPX

FDA

X

X

X

USDA

X

ADI/TSE Free

X

X

X

USP VI <87>

X

X

X

USP VI <88>

X

X

X

X

USP VI <661>
REACH

X

X

X

RoHS 3

X

X

X

Additional certificates for individual styles are available upon request

AVAILABLE SIZES
Style 3500 EPX

Style 3504 EPX

Thickness - inch (mm)3/32“ (2.4mm)

3/32“ (2.4mm)

Style 3510 EPX
3/32“ (2.4mm)

Tolerance - inch (mm)+/- 0.008 (0.2mm)+/- 0.008 (0.2mm)+/- 0.008 (0.2mm)

Sheet Sizes - inch (m)60“x 60“ (1.5m x 1.5m)

60“x 60“ (1.5m x 1.5m)

60“x 60“ (1.5m x 1.5m)

Leaders in Sealing Integrity
8

GYLON EPIX® | The Next Generation of PTFE Gasketing
INSTALLATION RECOMMENDATIONSFACTORS AFFECTING GASKET PERFORMANCEINSTALLATION

A gasket has one basic function: to create a positive seal between
two relatively stationary parts. The gasket must do a number ofdifferent jobs well to function properly - first, create an initial seal;
second, maintain the seal over a desired length of time; third, beeasily removed and replaced. Varying degrees of success aredependent on how well the gasket does the following:

A few simple precautionary measures must be observed during
installation to ensure the most satisfactory joint.
» The features of GYLON EPIX® significantly improve many of theproperties, such as compressibility, recovery, load retention,
sealability, etc. over traditional PTFE gasketing. Proper installation
practices are still critical to achieving optimum performance fromGYLON EPIX® gaskets; consult torque requirements in the tables
provided in this publication.
» For optimum performance the sealing surface should be no lessthan ½” wide.
» Center the gasket on the flange. This is extremely vital where raised
faces are involved.
» Be sure surface finish and flatness are satisfactory.
» Tighten the bolts to compress the gasket uniformly. This means goingfrom side to side around the joint. See correct bolting pattern below.
» Use a torque wrench, well-lubricated fasteners, and hardened flat
washers to ensure correct initial loading.
» All bolts should be tightened in one-third increments, according toproper bolting patterns.
» Make a final check pass at the target torque value moving
consecutively from bolt to bolt.
» Re-torque 12 to 24 hours after initial installation, whenever possible.
All applicable safety standards including lockout/tag-out proceduresshould be observed.
» Never use liquid or metallic based anti-stick or lubricating compounds
on the gaskets. Premature failure could occur as a result.

1. Seals system fluid.
2. Chemically resists the system fluid to prevent serious impairmentof its physical properties.
3. Deforms enough to flow into the imperfections on the gasket
seating surfaces to provide intimate contact between the gasket
and the sealing surfaces.
4. Withstands system temperatures without serious impairmentsof its performance properties.
5. Is resilient and creep resistant enough to maintain an adequate
portion of the applied load.
6. Has sufficient strength to resist crushing under the applied load,
and maintain its integrity when being handled and installed.
7. Does not contaminate the system fluid.
8. Does not promote corrosion of the gasket seating surfaces.
9. Is easily and cleanly removable at the time of replacement.
During the gasket product selection process that follows, werecommend that these nine (9) factors be used as a checklist fromthe viewpoint of the user’s degree of need for each factor and themanufacturer’s degree of compliance.

CORRECT BOLTING PATTERN
8143224105317
14326 97

CircularFour-Bolt

NoncircularMultibolt

SquareFour-Bolt

4 14 961121615211510 13 38CircularMultibolt

Leaders in Sealing Integrity
9GYLON EPIX® | The Next Generation of PTFE Gasketing
BOLT TORQUE VALUES FOR GYLON EPIX®

ASME B16.5 150# RAISED FACE FLANGES WITH A193 GRADE B7 BOLTS
Nom. Pipe Size
inches
22½
33½
4
5
68
10
1214161820
24# of bolts
444
8
8
88
8
12121216
162020Size of Bolts
inches
5/8
5/8
5/8
5/8
5/8
¾
¾
¾7/8
7/8
1111/811/8
1¼Internal Pressure
psig300
300
300
300
300
300
300
300300300300300300300
300

Minimum Torqueft. lbs.
526189506388111
150
141187238
226336296
422

Preferred Torqueft. lbs.
120120120120
120
200200200
320
320490
490
710
710
1000

Minimum torque values based on a minimum gasket stress of 3600 psi.
Preferred torque values based on a maximum gasket stress of 15,000 psi or 60,000 psi bolt stress, whichever occurs first.
Contact Garlock Application Engineering if flanges are non-metallic or if bolt grade is other than A193 B7.
ASME B16.5 300# RAISED FACE FLANGES WITH A193 GRADE B7 BOLTS
Nom. Pipe Size
inches
22½
3
3½
4
5
6
8
101214161820
24# of bolts
888888121216
1620
1624
24
24

Size of Bolts
inches
5/8
¾
¾
¾
¾
¾
¾
7/8
1

11/8
11/8
1¼
1¼
1¼
1½

Internal Pressure
psig
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800

Minimum Torqueft. lbs.
35
45
66
74
94
117
99
160
185
269
234
328
371
409
579

Preferred Torqueft. lbs.
108
141
200
200
200
200
200
320
490
710
652
912
1000
1000
1552

Minimum torque values based on a minimum gasket stress of 4800 psi to 5600 psi (depending on flange size).
Preferred torque values based on a maximum gasket stress of 15,000 psi or 60,000 psi bolt stress, whichever occurs first.
Contact Garlock Application Engineering if flanges are non-metallic or if bolt grade is other than A193 B7.

Leaders in Sealing Integrity
10

GYLON EPIX® | The Next Generation of PTFE Gasketing
GUIDANCE FOR GYLON EPIX®
In 150# Flat Face Smooth Fiber Reinforced Plastic (FRP) Flanges1

Nominal Size (Inch)

Torque (ft.lbs.)
3500 EPX3504 EPX

3510 EPX

177141.5

991921616333242449

416163362323468333366

10323264

1247

47

93

1467

67

134

166060

120

1866

66

132

206262

124

248787173

26 - 48

GYLON EPIX® can be used for these sizes.
Consult with Garlock Applications Engineering for bolt torque guidance.

150# Flat Face Smooth FRP Flange Sealability Testing – 150 psig Ambient Water

The table above shows the torque values required to achieve 300 psi gasket stress (3500 EPX and 3504 EPX) and 600 psi gasket stress(3510 EPX), and are applicable for 150# flat face FRP flanges with smooth faces (no surface profiles or raised features). These minimum stressvalues were determined by testing the three GYLON EPIX® styles in a 6” Class 150 FRP flange test rig with water at 150 psig and 180°F
and in laboratory test fixtures. Consult applications engineering if the flanges are PVC/CPVC and/or have a profiled finish. Never exceed themaximum allowable torque published by the FRP flange manufacturer. Doing so could result in flange/equipment damage.
1Leaders in Sealing Integrity11

Garlock Family of Companies
1666 Division Street
Palmyra, New York 14522 USA
1-800-448-6688 | 1-315-597-4811
Fax: 1-800-543-0598 | 1-315-597-3216

www.garlock.com© 2020 Garlock Family of Companies. All rights reserved. Garlock is
an EnPro Industries, Inc. family of companies (NYSE: NPO).
GSK 3-88 12.2020