Steel Ring

 Alternative Names 

Skeleton ring

Reinforcing ring

Inner and outer rings (specifically referring to the distinction between inner and outer rings when winding gaskets)

Metal ring

Wound gasket steel ring

V-shaped ring/W-shaped ring (depending on the cross-sectional shape)

Gasket support ring

Gasket Ring/Reinforcement Ring (commonly used in English

Product Introduction 

Core definition: The steel ring is one of the core components used for metal wound gaskets. It is usually made by stamping or winding high-elasticity and corrosion-resistant spring steel strips (such as 304, 316, 321 stainless steel or special alloys), with a cross-section in a specific "V" or "W" shape.

Main functions:

• Provide support and rigidity: Endow the gasket with the necessary structural strength to prevent it from being crushed or overly deformed under bolt preload and medium pressure, ensuring the stability of the seal.

• Positioning and guidance: Helps the winding tape maintain the correct position during installation and use to prevent it from coming loose.

• Auxiliary sealing: Under certain structures and pressures, its specific cross-sectional shape (such as W-shaped) can also play a certain auxiliary sealing role by itself.

• Compensation function: The highly elastic design enables it to absorb a certain amount of displacement caused by minor unevenness of the flange surface or thermal expansion and contraction.

• Key component: It is alternately wound with non-metallic filled tapes (such as graphite, PTFE, mica, etc.) to jointly form a high-performance metal wound gasket.

 Product Features 

High strength and rigidity: Made of high-strength spring steel, it can withstand extremely high bolt loads and internal medium pressures.

Excellent elasticity: The specific V/W cross-section design and high-quality materials endow it with good elastic recovery ability, enabling it to adapt to the slight deformation and thermal cycling of flanges.

High-temperature resistance: Depending on the material selection (such as 304, 316, 321, Inconel, Hastelloy, etc.), it can operate stably within a wide temperature range from -200°C to +1000°C (or even higher).

Corrosion resistance: Made of stainless steel or special alloys, it can resist the corrosion of various acids, alkalis, solvents, oils and other chemical media.

High pressure resistance: It is a key component for forming high-pressure wound gaskets and meeting the high-pressure grade requirements of standards such as ASME B16.20.

Precise geometric shape: Precise processing ensures that the cross-sectional shape and dimensional tolerances comply with strict standards, guaranteeing sealing performance and installation fit.

Creep resistance and relaxation: It can maintain good sealing force in long-term high-temperature and high-pressure environments, reducing the risk of leakage.

 Application Scenarios 

Steel rings (as the core components of wound gaskets) are widely used at flange connections that require reliable sealing, especially under harsh working conditions:

Petrochemical industry: Flange connections of reactors, towers, heat exchangers, valves and pumps in oil refineries and chemical plants. Handle high-temperature and high-pressure oil and gas as well as corrosive chemicals.

Power industry: High-temperature and high-pressure flanges for steam systems, feedwater systems, boilers, and steam turbines in thermal power plants and nuclear power plants.

Oil and gas extraction and transportation: Flange sealing for wellhead installations, pipelines, separators, and compressor stations.

Steelmaking and metallurgy: High-temperature furnaces and kilns, hot air ducts, flanges of gas purification equipment.

Pharmaceuticals and Food: Process pipelines and equipment that require high cleanliness or corrosion resistance (commonly made of materials such as 316L).

Shipbuilding and Marine Engineering: Flange sealing for engines, pipeline systems, and seawater treatment equipment.

Any critical flange connection that involves high temperature, high pressure, intense temperature cycling, strong corrosiveness or highly hazardous media and requires zero leakage.

 Product Advantages 

Outstanding sealing reliability: It provides long-term and stable sealing under extreme working conditions, significantly reducing the risk of leakage and ensuring safety and environmental protection.

Wide adaptability to working conditions: Through material selection, it can cover an extremely wide range of temperatures, pressures and corrosive media.

Excellent compensation capacity: The elastic design can compensate for minor defects, unevenness or thermal deformation on the flange surface.

High cost performance: Compared with pure metal gaskets or other complex sealing solutions, wound gaskets (including steel rings) not only meet high-performance requirements but also have relatively controllable costs and are easier to maintain and replace.

Standardization and interchangeability: Complies with international/domestic standards (such as ASME B16.20, DIN, GB/T), and is easy to purchase and replace.

Long service life: Under correct selection and installation, it has a long service life, reducing downtime and maintenance costs.

 Customized Process 

Steel rims are usually custom-made as a whole by winding gaskets. The process is as follows:

Demand communication

The customer provides the flange standard and dimensions (nominal diameter DN/PN, or specific inner diameter ID/ outer diameter OD/ thickness).

Clarify the working conditions: medium composition, temperature, pressure, and whether it is circulating.

Clarify the material requirements: steel ring material, filling band material.

Clarify standards or special requirements: such as ASME B16.20, DIN, or customer-specific drawings/specifications.

Confirm the quantity and delivery date.

Technical Assessment and Quotation

Engineers assess the rationality of the working conditions and recommend appropriate steel ring materials, cross-sectional shapes (V/W), and inner and outer ring configurations.

Confirm the type of gasket (basic type, with inner ring, with inner and outer rings).

Provide a formal quotation sheet including material, size, standard, price and delivery date.

Order Confirmation: The customer confirms the quotation and places the purchase order.

Design and Production Preparation:

The technical department will produce detailed gasket drawings (including steel ring specifications) based on the order requirements and conduct internal approval.

Prepare molds (if special cross-sections or dimensions are required) and raw materials (specific steel strips).

Raw material inspection: Verify the material proof of the purchased steel strips and conduct necessary re-inspections upon entry (such as spectral analysis, dimensions, and surface).

Manufacturing and Processing:

Steel ring forming: Using precision winding machines or stamping equipment, steel strips are processed into ring-shaped parts that meet the cross-sectional shape (V/W) and diameter requirements. Weld the joint (usually by argon arc welding) and grind it smooth.

Winding: Position the formed steel ring (inner ring, outer ring) on the winding machine and alternately wind it with non-metallic filling tape to the specified number of layers, density and thickness.

Shaping and finishing: Shape and compact the wound gasket to ensure its flatness and dimensional accuracy. The outer ring may undergo anti-loosening spot welding.

Inspection and Testing: See Part Seven.

Marking and Packaging: Marking shall be carried out in accordance with standards or customer requirements (material, size, standard number, batch number, etc.), and the packaging shall be rust-proof and impact-proof.

Shipment: Attach quality inspection reports and ship on time.

 Quality Inspection Process 

The quality inspection of steel rims is usually integrated into the entire quality inspection process of wound gaskets. Key links include:

Raw material inspection:

Steel strip material certificate review (MTC).

Random inspection of steel strip dimensions (width, thickness).

Surface quality inspection of steel strips (no cracks, pits, severe scratches, or oxide scale).

(If necessary) Retest the spectral analysis of chemical composition.

Process Inspection

Steel ring forming: Cross-sectional shape, dimensions (inner diameter, outer diameter, cross-sectional height, Angle), roundness, joint welding quality (no cracks, incomplete fusion, pores, and smooth grinding).

Winding: Accuracy of rim positioning, number of winding layers, uniformity of winding tightness, position of filling band, overall thickness.

Finished product Inspection

Visual inspection: The surface is clean, free of oil stains, rust and damage. There is no damage or overflow in the non-metallic filling tape. The signs are clear and correct.

Dimensional inspection

Inner diameter and outer diameter (using calipers, π rulers or special measuring tools).

Thickness (measured at multiple points, using a micrometer or caliper).

Key cross-sectional dimensions (such as V/W height and Angle, using a projector or dedicated measuring tools).

Flatness (check on the platform).

Material verification: (Usually, the batch material certificate is checked. If necessary, the spectrum of the finished product is spot-checked.)

Hardness test: (Test the hardness of the steel ring according to the standard or customer requirements to ensure its elastic performance).

Compression and rebound performance test: (According to standards such as GB/T 12622, test the overall compression rate, rebound rate and sealing performance of the gasket on a dedicated testing machine. This is the most important indirect verification of the function of the steel ring.)

(Special Requirements) Leakage rate test: Test the actual sealing performance of the gasket under simulated working conditions.