Introduction to Spiral Wound Gaskets

Spiral wound gaskets are sealing gaskets formed by alternately winding metal strips and non-metallic filler strips. They combine the strength of metal with the sealing properties of non-metallic materials, making them high-performance sealing components widely used in industrial pipelines and equipment.

 

 Core Characteristics

Characteristic	Description	Advantages
Excellent Sealing Performance	Multiple sealing barriers with metal and non-metal material combination	Suitable for high-temperature and high-pressure conditions
Good Elastic Compensation	Wound structure allows compression and rebound	Adapts to uneven flange surfaces
High Temperature and Pressure Resistance	Maximum operating temperature up to 800°C, pressure up to 25MPa	Suitable for harsh working conditions
Resistance to Creep and Relaxation	Metal strips provide mechanical strength and resist sustained loads	Maintains long-term sealing stability
Multiple Material Combinations	Metal and filler materials can be selected based on the medium	Adapts to various corrosive environments

 Basic Structure

Component	Material Options	Function
Metal Strip	304/316 stainless steel, Inconel, titanium alloy, etc	Provides mechanical strength and elasticity
Filler Material	Graphite, PTFE, ceramic fiber, etc.	Provides primary sealing function
Inner and Outer Rings	Usually same material as metal strip	Positioning and reinforcement

Type Classification

Type	Structural Features	Applicable Standards	Applications
Basic Type	No inner or outer rings	ASME B16.20	Tongue-and-groove flange faces
Inner Ring Type	With inner ring	EN 1092-1	Raised face flanges
Outer Ring Type	Outer Ring Type	DIN 2696	Flat face flanges
Inner and Outer Ring Type	With both inner and outer rings	JB/T 90	High-pressure applications

 

Performance Parameters Table

Performance Indicator	Graphite Filler	PTFE Filler	Ceramic Fiber Filler	Test Standard
Operating Temperature (°C)	-200~800	-200~260	-200~1100	ASTM F38
Operating Pressure (MPa)	≤25	≤10	≤20	ASME B16.20
Compression Rate (%)	18~30	15~25	20~35	ASTM F36
Recovery Rate (%)	≥17	≥15	≥20	ASTM F36
Stress Relaxation Rate (%)	≤15	≤20	≤18	ASTM F38

 

 Selection Guide

1. Material Selection Principles:

   · Metal strip material should be equal to or better than flange material

   · Filler material must be compatible with process medium

   · Consider temperature and pressure fluctuations

2. Size Determination:

   · Determine gasket size according to flange standards

   · Consider bolt load and flange stiffness

   · Reserve appropriate compression space

3. Special Condition Considerations:

   · Use more elastic materials for thermal cycling conditions

   · Use advanced alloy materials for corrosive environments

   · Special treatment required for ultra-high vacuum environments

 

 Installation and Usage Requirements

1. Pre-Installation Inspection:

   · Flange sealing surfaces should be clean and undamaged

   · Confirm correct gasket model and materials

   · Check if gasket is intact and undamaged

2. Installation Specifications:

   · Use positioning tools to ensure alignment

   · Tighten bolts gradually in diagonal sequence

   · Achieve specified bolt preload

3. Maintenance Recommendations:

   · Regularly check bolt tightness

   · Re-tighten after thermal cycling

   · Inspect gasket compression status during shutdown

 

Application Fields

1. Petrochemical Industry: Reactors, heat exchangers, pipeline flanges

2. Power Industry: Steam turbines, boiler systems

3. Refining Units: Hydrocracking, catalytic cracking units

4. Nuclear Power Industry: Nuclear-grade equipment sealing

5. Aerospace: Engine pipeline systems

 

Spiral wound gaskets, with their unique structure and excellent sealing performance, are the preferred sealing elements for high-temperature and high-pressure conditions. Through reasonable material selection and correct installation, they can provide reliable long-term sealing for various industrial equipment. Their flexibility in multi-material combinations allows them to adapt to extreme conditions ranging from cryogenic to high-temperature and high-pressure environments.