Our hydrophilic water-swelling rubber rings are compounded with modified EPDM and super absorbent polymer; they expand automatically on contact with water (150%–300% volume expansion), filling tiny gaps to help block water seepage. The rings are anti-aging, corrosion-resistant, non-toxic, and eco-friendly, and are used in basement, tunnel, pipeline, and rebar waterproofing projects. Custom sizes, colors, expansion rates, and logos are available.

Product Introduction

Many pipeline penetration points, cable ducts, manhole covers, and equipment joints face the same issue: rainwater, groundwater, mud, and odours can enter through small gaps. Conventional rubber seals fill the gap mechanically, but they cannot actively block water under uneven settlement, temperature deformation, or minor variations in gap size.

Our water-swellable rubber seal ring is designed to address this problem. Made from a hydrophilic rubber material, it remains flexible during installation and automatically expands after absorbing water. Once expanded, the rubber tightly fills the gap and forms a continuous waterproof sealing layer, helping to prevent water leakage, mud ingress, and odour backflow.

This seal ring is widely used in cable pipe penetrations, manhole covers, pipeline joints, underground equipment bases, sewage treatment tanks, construction expansion joints, and other waterproof sealing applications.

The water-swellable rubber seal ring contains hydrophilic components within the rubber material. When the ring comes into contact with water, the material gradually absorbs water and expands in volume. This expansion creates a compressive force that presses the rubber against the sealing surface, filling irregular gaps and forming a reliable water-stop effect.

Unlike ordinary static seals, this product provides both:

Initial sealing effect from rubber elasticity during installation

Active sealing effect after water absorption and expansion

It is particularly suitable for applications where slight displacement, vibration, or gap variation may occur.

✅ Water-Activated Expansion Sealing After contacting water, the rubber ring expands to fill gaps and forms a tight waterproof seal. It helps prevent rainwater, groundwater, and mud from entering pipes and equipment.

✅ Good Elasticity and Compression Recovery The rubber material maintains flexibility under compression, vibration, and temperature changes. It is less prone to hardening, cracking, or loss of sealing performance after long-term use.

✅ Broad Application Scenarios Suitable for cable ducts, manhole covers, pipeline joints, equipment bases, sewage tanks, construction joints, and other underground engineering sealing applications.

✅ Easy to Install No complex tools are required. Place the seal ring into the sealing groove or joint position, then install and compress it. Suitable for on-site installation and equipment assembly.

✅ Durable Rubber Material With good resistance to weathering, aging, and water, it can be used for extended periods in humid environments, outdoor pipelines, and underground facilities.

Cable Duct Sealing

Used for sealing cable duct entrances and exits to prevent rainwater and groundwater from entering the pipeline along the cable.

Manhole Cover Sealing

Installed between the manhole cover and base to reduce water ingress, mud leakage, and odour backflow.

Pipeline Joint Sealing

Suitable for pipe connection positions, expansion joints, and flexible joints, helping to compensate for minor displacement gaps.

Equipment Base Sealing

Used for underground equipment bases, control cabinets, pump stations, and sewage treatment facilities to improve waterproof performance.

Construction Joint Sealing

Suitable for construction joints, reserved openings, and penetration points in civil engineering and infrastructure projects.

Clean the sealing groove and the contact surface to remove dust, mud, and oil.

Check that the seal ring is intact and free from cracks or damage.

Place the water-swellable rubber ring evenly into the sealing groove or joint position.

Install the cover, flange, or pipe fitting, and compress the seal ring properly.

Ensure uniform compression around the ring to form a reliable initial seal.

Avoid soaking the ring in water for an extended period before installation.

Q: How long does it take to expand after contacting water?

A: The expansion speed depends on water temperature, water quality, and the rubber formula. Generally, it begins to absorb water gradually and forms a stable sealing effect within a certain period of time.

Q: Can it be used repeatedly?

A: After fully expanding and drying, the sealing performance may decrease. It is recommended to assess suitability based on the actual operating conditions.

Q: Can you provide custom sizes?

A: Yes. We support custom inner diameter, outer diameter, thickness, and cross-section shape according to your drawings or samples.

Q: Is this seal ring oil resistant?

A: Standard water-swellable rubber is mainly designed for water sealing. For oily environments, please inform us of the actual medium so that we can recommend a more suitable formula.