Expanded PTFE Sheet/tape

Ⅰ、Features

Polytetrafluoroethylene is a new type of polymer materials. Polytetrafluoroethylene resin by special processing methods. White, flexible and flexible, with a network of fine fibers connected to form a network of these fine fibers to form numerous pores, the expanded PTFE can be arbitrary bending (over 360 degrees), the expansion of polytetrafluoroethylene Has a good anti-chemical, anti-wear properties and extremely high temperature, low temperature capability, ideal for industrial liquid seal.

Ⅱ、Types and Specifications:

Ⅲ、Main Properties:

Ⅳ、Applications

PTFE gasket for pipe, flange and rubber, plastic, enamel, graphite pieces of industrial machinery in the joints at the sealing material.

 PTFE Expansion Tape Product Introduction

PTFE expansion tape is a scalable sealing material made from pure polytetrafluoroethylene (PTFE) through special processing. Its unique thermal expansion property makes it an ideal sealing solution for high-temperature and high-pressure applications.

Core Characteristics

Property	Technical Parameters	Core Advantages
Intelligent Expansion	Begins expansion at 150°C, up to 200% expansion rate	Automatic gap compensation
Temperature Resistance	-200°C ~ +260°C long-term stable operation	Reliable performance in extreme temperatures
Multiple Sealing Mechanisms	Combines mechanical compression and thermal expansion sealing	Dual protection for enhanced safety
Safety & Environmental Compliance	Asbestos-free, FDA certified (21 CFR 177.1550)	Safe for food and pharmaceutical applications

Product Advantages

· Emergency Sealing: Automatically compensates for seal gaps when temperature rises

· Easy Installation: Direct winding application, no pre-forming required

· Long-Term Stability: Service life of 3-5 years at 260°C

· Versatility: Suitable for irregular sealing surfaces

Typical Applications

Industrial Sealing

✅ Emergency sealing for high-temperature flanges (sudden leaks)

✅ Supplementary sealing for valve stuffing boxes

Energy Equipment

✅ Compensation sealing for steam pipelines

✅ Maintenance sealing for heat exchangers

Specialized Fields

✅ Nuclear power plant pipeline sealing (RCC-M certified)

✅ Spacecraft fuel pipeline sealing

Usage Guide

1. Installation Steps

· Clean sealing surface (Ra ≤ 3.2μm)

· Spiral winding (50% overlap rate)

· Initial compression force: 10-15 N/mm²

2. Activation Conditions

· Minimum activation temperature: 150°C

· Optimal activation range: 180-220°C

· Full expansion time: 30-60 minutes

3. Maintenance Recommendations

· Annual inspection of expansion status

· Re-tightening during system shutdown

· Maximum 3 reuses

Quality Certifications

· API 6A (Petroleum Equipment Certification)

· ISO 9001 Quality Management System

· PED 2014/68/EU (Pressure Equipment Directive)

· ASME B16.20 (Pipe Flange Sealing)

Selection Guide

Application	Recommended Type	Special Features
Conventional Sealing	1.0mm Standard Type	General purpose
High Pressure Conditions	1.5mm Thick Type	Enhanced pressure resistance
Quick Emergency Response	Low-Temperature Activation Type (starts at 120°C)	Faster response
Nuclear Applications	Special Type with Barrier Layer	RCC-M nuclear grade

Detailed Technical Parameters

Parameter	Value Range/Description	Test Standard
Chemical Composition	Pure PTFE or modified additives (graphite, glass fiber)	ASTM D4894
Density	2.14-2.20 g/cm³	ISO 1183
Tensile Strength Longitudinal	≥15 MPa, Transverse ≥10 MPa	ASTM D638
Elongation at Break	200-400%	ASTM D638
Dielectric Constant	1.8-2.2 (1MHz)	ASTM D150
Volume Resistivity	≥10¹⁸ Ω·cm	ASTM D257
Friction Coefficient	0.05-0.10 (dynamic, steel vs PTFE)	ASTM D1894
Thermal Expansion Coefficient	10-15×10⁻⁵/℃ (20-100℃)	ASTM E831
Flammability	Non-flammable (oxygen index ≥95%)	ASTM D2863

Detailed Specifications Comparison

Parameter	Ultra-Thin (Precision)	Standard	Thick (High Pressure)	Wide Width (Large Diameter)
Thickness (mm)	0.04-0.07	0.08-0.12	0.15-0.30	0.10-0.15
Width (mm)	12	19, 25	25, 50	50, 75, 100
Pressure Rating (MPa)	≤5	≤16	≤40	≤16
Temperature Range (°C)	-100~+200	-200~+260	-200~+300	-200~+260
Typical Applications	Instrument pipes, electronic components	Water pipes, gas pipes	High pressure systems	Large chemical flanges

Chemical Compatibility Guide

Medium Type	Tape Selection Requirements	Prohibited Scenarios
Oxygen/High Purity Gases	Grease-free grade (pink), residual grease ≤0.1mg/m²	Standard white tape
Strong Acids (e.g., concentrated sulfuric acid)	Pure PTFE without additives, thickness ≥0.15mm	Graphite modified types
Food/Pharmaceutical	FDA certified, heavy metal content ≤0.005%	Industrial general purpose
Cryogenic (LNG)	-200°C low temperature toughened treatment, no cracking risk	Recycled material tapes

Industry Application Classification

Industry	Specific Application Scenarios	Special Requirements
Petrochemical	Reactor flange sealing, corrosive media pipelines (sulfuric acid, hydrochloric acid)	High pressure resistance (≥10MPa), stress corrosion resistance
Food & Pharmaceutical	Sterile pipelines, fermentation tank threaded connections	FDA certified, no leachables
Energy & Power	team turbine pipelines, nuclear plant cooling systems	Radiation resistance, high temperature resistance (300°C short-term)
Semiconductor	High purity gas delivery (silane, helium)	Dust-free, oil-free, ESD protection
Aerospace	Hydraulic systems, fuel pipelines	MIL-STD-27730A standard
Civil Construction	HVAC, gas inlet pipes	Flame retardancy (UL94 V-0)

Detailed Physical Properties

Property	Test Conditions	Typical Value	Unit	Test Standard
Density	23°C	2.15-2.20	g/cm³	ISO 1183
Tensile Strength	23°C,50mm/min	15-30	MPa	ASTM D638
Elongation at Break	23°C	200-400	%	ASTM D638
Compression Set	0MPa, 24h, 23°C	≤15	%	ASTM D395
Thermal Conductivity	100°C	0.24-0.28	W/(m·K)	ASTM E1461
Linear Expansion Coefficient	20-100°C	12×10⁻⁵	/°C	ASTM E831
Friction Coefficient	Steel vs PTFE, 0.5m/s	0.05-0.08	-	ASTM D1894

Chemical Resistance Table

Chemical Medium	Concentration	Resistance (23°C)	Max Temperature	Failure Mode
Sulfuric Acid	98%	Excellent	200°C	Decomposes >260°C producing HF
Sodium Hydroxide	50%	Good (≤100°C)	80°C	Penetration and swelling at high temperature
Acetone	100%	Excellent (grease-free type)	-200°C	Grease causes explosion
Wet Chlorine	100%	Poor	Prohibited	Stress corrosion cracking
Gasoline	Commercial 92#	Excellent	120°C	Weight gain <0.1% after long-term immersion
Liquid Oxygen	-183°C	Excellent (grease-free type)	-200°C	Grease causes explosion

Testing Standards Comparison

Test Item	Chinese Standard	International Standard	Test Method Highlights
Thickness Uniformity	GB/T 6672	ISO 4591	10-point micrometer measurement, deviation ≤±0.01mm
Tensile Performance	GB/T 1040.3	ASTM D638	Dumbbell specimen, 50mm/min tensile speed
Sealing Test	HG/T 3987	EN 751-1	1.5× working pressure, hold 30 minutes no leakage
Volatile Content	GB/T 2914	ASTM D1901	105°C oven 2h, weight loss ≤0.5%
Food Safety	GB 4806.1	FDA 21	CFR 177 Heavy metals (Pb/Cd/Hg) ≤0.005mg/kg
Flame Retardancy	GB/T 2408	UL94	Vertical burn test, self-extinguishing time <10s

Special Condition Adaptation Guide

Extreme Condition	Adaptation Solution	Verification Standard
Ultra High Pressure (>40MPa)	Glass fiber reinforced PTFE tape (0.3mm thick) + MoS₂ coating	API 6A Appendix F
High Radiation Environment	Gray tape with radiation resistant additives (lead powder), cumulative dose tolerance ≥10⁶ Gy	ASTM D1879
Ultra Clean Requirements	Silicon-free, dust-free type, particle release <0.1μm (100 particles/ft³)	ISO 14644-1 Class 1
Dynamic Vibration Scenarios	Composite use with pre-applied thread lock adhesive (e.g., Loctite 577)	DIN 267-27