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PTFE Coated Bolts

Xylan Coating

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Xylan Industrial Coating Service

Xylan coating prevents leaks past thread
Pressure vessels, valves, pipe unions, storage tanks, reactors, pipelines and other fluid containment equipment are often fitted with threaded plugs for inspection, pressure relief, filling or tapping.

Coatings on pipe plugs not only improve their performance and reliability but also make them easier to use. A thin film of Xylan eliminates the PTFE tape normally wrapped around the threads to seal them.

In addition, the corrosion protection and low-friction properties of the coating greatly reduce breakout torques, enabling users to remove the plugs at a later date without destroying them.

In most instances, the pipe plugs may be re-used without difficulty.

Xylan coatings are also available in many colors, enabling users to color-code particular plug sizes and alloys.

Xylan 1014

Main Properties:

High temperature resistant. Low coefficient of friction. Abrasion / wear resistant. Dry film lubricant. Thermoset. Wide use temperature.

Typical Applications: Any mating surface which requires lubrication. Hinge pins. Piston casing. Compressors. Fasteners.

Description: Resin-bonded, thermosetting, dry-film lubricant which, when compared to Xylan 1010 contains significantly more bonding resin relative to its content of PTFE lubricant. Altering the formula in this manner produces finishes which are harder, more abrasion resistant, glossier, and less porous. Frictional values remain low and very predictable.

Working temp. range (continuous) -195°C/-320°F to 260/500°F Working temp. range (intermittent) -195°C/-320°F to 285°C/545°F

Xylan 1052

Main Properties:

High temperature resistant. High load carrying capacity. Abrasion / wear resistant. Thermoset.

Typical Applications: Applications to prevent wear of mating surfaces under extreme load such as bearings, sealing rings, and valve springs.

Main Properties:

High temperature resistant. Low coefficient of friction. Abrasion / wear resistant. Thermoset. Wide use temperature. Corrosion resistant. Controlled torque.

Typical Applications: Threaded fasteners.

Description: Resin-bonded, thermosetting, dry film lubricant. It is formulated for high-pressure, low-speed wear applications and provides long-term lubrication for bearing surfaces subjected to extreme pressures, up to 150,000 psi (10,500 kg/cm2). The coating utilizes a unique dual lubrication system of PTFE and MoS2 and is superior to  moly greases which wash away and PTFE coatings which  cold flow. Resin-bonded lubricants in Xylan 1052 stay on the job, even in harsh chemical environments.

Working temp. range (continuous) -195°C/-320°F to 260°C/500°F Working temp. range (intermittent) -195°C/-320°F to 285°C/545°F

Xylan 1070

Main Properties:

High temperature resistant. Low coefficient of friction. Abrasion / wear resistant. Thermoset. Wide use temperature. Corrosion resistant. Controlled torque.

Typical Applications: Threaded fasteners.

Description: Resin-bonded, thermosetting, PTFE based, dry-film lubricant. It has extra corrosion protection and issued to coat large studs (B7), nuts, flanges, and related hardware for sub-sea and splash-zone service. Because of its predictable, low-friction properties, less make-up torque is required to produce the specified tension. During assembly, clamp loads are increased; scatter is reduced. In fact, the frictional characteristics are the most predictable of any lubricant, coating, or plating used on bolting. The low friction properties also reduce break-out torque, which allows removal of bolting with a wrench instead of a blowtorch.
Application: Conventional spray.

Working temp. range (continuous) -195°C/-320°F to 260°C/500°F
Working temp. range (intermittent) -195°C/-320°F to 285°C/545°F

Xylan 1400

Main Properties:

Corrosion resistant. Chemical resistant. Weathering resistant. Acid rain resistant.

Typical Applications: Threaded fasteners for the building, chemical process, oil and off shore industries.

Description: A recoatable “RC” coating developed to protect large fasteners and chemical processing equipment from chemical exposure (especially those with high pH). Although it contains a small percentage of PTFE lubricant to facilitate installation and prevent galling, it is considered a barrier coating rather than a dry film lubricant.

Working temp. range (continuous) -50°C/-58°F to 175°C/350°F

Xylan 1424

Main Properties:

Dry film lubricant. Corrosion resistant.

Typical Applications: Any mating surface which requires lubrication. Hinge pins. Piston casing. Compressors. Threaded fasteners. Description: This VOC compliant*, resin-bonded, PTFE based coating is primarily formulated for use on fasteners to prevent corrosion and facilitate make-up torque.

Working temp. range (continuous) -50°C/-58°F to 175°C/347°F
Working temp. range (intermittent) -50°C/-58°F to 200°C/392°F

More Xylan Inforamation

Xylan Coated Bolts

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Xylan Coated Bolts
Xylan Coated Bolts

Xylan Coated Bolts

Xylan 1010, 1070, 1014, 1052 and now 1424 have been used as bolt coatings for almost a quarter century now. Most major Oil and Chemical Companies recognizing that maintenance is a huge issue have made coated bolt specifications for bolted high pressure flange connections. The various properties on the Xylan give excellent make up and brake out torque and reduce the need for high risk cutting torches or high cost bolt cutting when maintenance is required.

Xylan 1014 in bolt coatings used for its good lubricity, chemical and abrasion resistance.

Xylan 1052 for coated bolts used for its excellent lubricity.

Xylan 1070 and 1010 where the pioneers in the field – used for the lubricity and chemical inertness.

With VOCs an ever present issue these days Whitford has made a low VOC version 1424 which Sigma applies to achieve the results need in a coated bolt connection and to stay complaint in a green economy.

Xylan coated bolts come in many tints and the coated bolts are often coordinated with standard corporate color branding schemes. While very light shades are possible most of the popular hues range from a Dark Yellow to black with Reds and Blues and greens being the most widespread.

Coated Bolts

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Sigma Fasteners manufacturers coated studs to meet major Chemical and Oil Company specifications. Sizes range from 1/2 inch – 3 1/2 and larger.

Blue Coated Stud Bolts
Coated Stud Bolts

Sigma coated bolts have a two-layer structure of special pretreatment polymer film and under-treatment layer. Phosphate Pre-treatment technique insures the physical performance of product without changing and fluropolymer top coating results in a better performance in resisting chemical and seawater corrosion. SermaGard coating is different from PTFE because of their strong corrosion resistant ability. Xylan can be different per customers request to meet various environmental working conditions.

  • Xylan
  • SermaGard
  • PTFE
  • PTFE
  • Moly

Xyan combined with an advanced treatment technology; the film is thin but is excellent in corrosion resistance which prolongs the lifespan of the product.  Non-stick and low friction properties can make-up the torque coefficient which is easy to install and disassembling. Property of chemical & weather resistance make it suitable to various severe environments.

Xyaln and SermaGard coatings are the best choice in offshore, oilfield and petrochemical precision equipment against corrosion. Its properties are particularly suitable for surface corrosion prevention of underwater precision equipment including Christmas tree, BOP and pipelines and other parts.

Xylan coating properties:

Low friction ( as low as 0.055)

Remarkable adhesion

Unusual resistance to wear and abrasion

Excellent resistance to corrosion

Resistance to chipping

Resistance to the elements: weather, sunlight, salt water

Working temperature range from: -190 to + 260° C

Available in a wide range of colors

Fluoropolymer Coated Bolt Torque

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API 6A is an International Standard which specifies requirements and gives recommendations for the performance, dimensional and functional interchangeability, design, materials, testing, inspection, welding, marking, handling, storing, shipment, purchasing, repair and re-manufacture of wellhead and well tree equipment for use in the petroleum and natural gas industries.

Torque Value Chart
Download Torque Value Chart

Covering bolts on Wellhead Equipment, Valves and chokes, and loose flanged connectors.

TORQUE FOR FLANGE BOLTING (B7/L7 STUDS)*

ANSI / API 6A / ISO 10423:2003 Feb. 1, 2005
ASTM A193 Grade B7 Tensile and Yield Strength
2 1/2″ and under – tensile  125 ksi; yield strength 105 ksi
Over 2 1/2″ to 4″ – tensile 115 ksi; yield 95 ksi
Over 4″ to 7″ – tensile 100; yield 75 ksi

ASTM A320 L7 Tensile and Yield Strength
Only covers 2 1/2″ and under – tensile  125 ksi; yield strength 105 ksi

Source: API 6-A, 19th Appendix D, Table D1 &
D2
Stud Diameter Tension PTFE Coated Bolt coefficient of Friction Plain Bolt coefficient of Friction
Size Ibf Torque Torque Torque Torque
Inch Nm Ft. lbs Nm Ft. lbs
f=0.07 f=0.07 f=0.13 f=0.13
1/2″ 7450 48 35 80 59
5/8″ 11865 92 68 155 115
3/4″ 17559 160 118 270 200
7/8″ 24241 253 188 429 319
1″ 31802 376 279 639 474
1 1/8″ 41499 540 401 925 686
1 1/4″ 52484 745 553 1285 953
1 3/8″ 64759 996 739 1727 1281
1 1/2″ 78322 1297 962 2261 1677
1 5/8″ 93173 1653 1226 2894 2146
1 3/4″ 109313 2069 1534 3636 2696
1 7/8″ 126741 2549 1890 4493 3332
2″ 145458 3097 2297 5476 4061
2 1/4″ 186758 4418 3276 7851 5822
2 1/2″ 233212 6068 4500 10828 8030
2 5/8″ 233765 6394 4716 11429 8430
2 3/4″ 257694 7354 5424 13168 9712
3″ 309050 9555 7047 17156 12654
3 1/4″ 365070 12154 8965 21878 16136
3 3/4″ 491099 18685 13782 33766 24905
3 7/8″ 525521 20620 15208 37293 27506
4″ 561108 22683 16730 41057 30282

*This chart is for general practice purposes only and should not be in the engineering or design of any products. The most current edition of the API specification may be obtained on the API Standards website to make sure you have the most current edition of API 6A. For most the accurate references in critical situations torque values should be replaced with field measured tension values. Accurate stud tension is difficult to attain using torque, because friction has a significant effect on the torque–tension relationship. Any thread damage (however minor), additional lubrication, or standard deviations within the range can change friction and thereby the expected outcome.