15*20mm Bentonite Hydrophilic Expansion Waterbar Water Swelling Water Stop Strip

• Customization: Available
• After-sales Service: 3 Year
• Application: Indoor, Outdoor
• Model NO.: JT-BW08
• Certification: CE, ISO, RoHS
• Shape: Strip
• Size: 10X20mm, 15X20mm, 20X25mm, 20X30mm, 30X40mm
• Type: Roofing and Waterproofing
• Colour: Black/Red/Blue/Customized
• Expansion Rate: 150%-600%
• Surface Treatment: Film Coated
• Tensile Strength(MPa): ≥22
• Density(Mg/M3): 1.1-1.3
• Elongation at Break(%): 400
• Working Temperature: -40-120 Celsius
• Hardness: 30-90 Shore
• Usage: Tunnel, Dam, Basement, Underground Concrete Joint,
• Transport Package: According to Customer Needs
• Specification: Customized
• Trademark: HengJingGong
• Origin: China
• HS Code: 4008290000
• Package Size: 35.00cm * 35.00cm * 26.00cm
• Package Gross Weight: 1.000kg

Product Description

Product Description

Bentonite waterstop is an eco-friendly, water-swellable sealing strip based on natural sodium bentonite. Blended with rubber, super-absorbent resin and special additives, it remains soft and plastic when dry, then expands 2–3 times in volume upon contact with water. Under confinement it generates high contact pressure, sealing concrete joints, cracks and pipe penetrations "by water itself". Non-toxic, acid/alkali resistant and repeatedly swellable, it stays flexible down to –30 °C. Installation is simple—just stick or nail in place; no heating or solvents are required, and total cost is lower than traditional steel waterstops.
Main Types
1.PN Putty Type
Soft, black putty with aggressive self-adhesion; easy to cut and press into irregular gaps; swell ratio 150 %–400 %.
2.BW-S Slow-Swell Type
Contains delayed-expansion agents that reduce swelling speed ≥ 50 %, preventing premature expansion and fall-off in rainy or damp conditions.
3.Moulded (Vulcanized Rubber) Type
Vulcanized to give moderate hardness and tensile strength ≥ 3.5 MPa; withstands high water pressure; ideal for shield tunnel segments and pipe-jacking joints.
4.Composite Strip with Grout Hose
A 6–8 mm injection hose is embedded in the centre; bentonite first swells to stop water, then grout can be injected later for secondary sealing—used in tunnel deformation joints and critical pipe bundles.
5.Reinforced Mesh Type
Nylon or glass-fibre mesh inside increases tensile strength threefold, preventing rupture under high expansion stress; suited for wide joints (≥ 30 mm) and high-pressure tunnels.
6.Self-Adhesive Type
Back-coated with high-temperature pressure-sensitive adhesive; simply peel off the release film and press onto concrete—no nails needed; popular for basement walls and swimming-pool horizontal construction joints.

Bentonite Waterstop Working principle

Hydrophilic waterstop strips maintain a flexible, strip-like form when dry. Upon contact with water, they rapidly expand in volume (typically by 150% to 600%, with some products reaching up to 1000%). They compress to fill voids within concrete joints, forming a dense waterproof barrier that prevents water penetration.

Sizes:

Width: 10 mm, 15 mm, 20 mm, 30 mm, 40 mm, 50 mm.
Height: 10 mm, 20 mm, 30 mm, 25 mm, 40 mm, 50 mm, 60 mm.
Color: black, red and other colors also can be customized.
Note: Other specifications also can be customized.

Feature

1.Highly effective waterproofing: It expands rapidly upon contact with water, can tightly fill various gaps to form a sealing barrier, with excellent waterproofing performance and high pressure resistance;

2.Self-healing function: It can continuously expand to seal new gaps caused by building settlement, ensuring waterproofing effectiveness; 

3.Stable and durable characteristics: Even after long-term immersion in water, it can still effectively perform waterproofing functions, has strong resistance to aging, and has a long service life;

Specification

Bentonite Waterstop Strip Parameters
NO.	ITEM	Result
		PN-150	PN-220	PN-300
1	Expansion rate/%≥	150	220	300
2	Flow at High Temperature (80℃×5h)	No fiow	No fiow	No fiow
3	Low temperature test (-20℃×5h)	No crack	No crack	No crack
4	Peel strength	0.05MPa
5	Shear Strength	1.0MPa
6	Hydrostatic Pressure	1.2MPa

Polymer Waterstop Strip Parameters
Physical properties		PZ-150	PZ-250	PZ-400	PZ-600
Hardness (shore A)		42±7	42±7	45±7	48±7
Tensile strength		3.5 Mpa (min)	3.5 Mpa (min)	3 Mpa (min)	3 Mpa (min)
Elongation		450% (min)	450% (min)	350% (min)	350% (min)
Expansion rate		150%	250%	400%	600%
Repeated water immersion test	Tensile strength	3 Mpa (min)	3 Mpa (min)	2 Mpa (min)	2 Mpa (min)
	Elongation	350% (min)	350% (min)	250% (min)	250% (min)
	Expansion rate	150%	250%	300%	500%
Low temperature bending (-20°C*2h)		No crack	No crack	No crack	No crack

Product Details

 Bentonite water stop strips are mainly used in "water seepage" concrete joints. Common scenarios are as follows
    1.Basement slabs and walls – horizontal/vertical construction joints, replacement for steel water bars, no welding or grooving needed.
    2.Metro tunnels & culverts – segment joints, pipe-jacking interfaces, deformation joints; slow-swell grades resist high pressure without premature expansion.
    3.Sewage plants, swimming pools, potable-water tanks – acid/alkali resistant, non-toxic, seals around wall penetrations and pool joints in one step.
    4.Dams & culverts – cast-in-place panel joints, workable in rainy seasons, withstands 1.5–2.5 MPa water head after swelling.
    5.Green roofs & sunken plazas – permanently damp and hard to repair; embed the strip during construction to cut future leakage risk.
    Put bentonite waterstop in any buried concrete joint that might see water, and let the strip swell itself shut when the water arrives.

Packaging & Shipping

Company Profile

Hengshui Jingtong Rubber Co., Ltd., located in Hebei Province's Hengshui City, is a professional manufacturer of engineering rubber products. Our product range includes bridge bearings, expansion joints, water stop strips, water stop belts, inflatable cores, building deformation joint device and water plugs, which are widely used in bridge, tunnel, water conservancy, and power engineering projects. The company boasts advanced technology and mature processes to ensure reliable product quality.

We have a professional technical team and a comprehensive after-sales service system to ensure customers receive high-cost-performance products and attentive service. Hengshui Jingtong Rubber Co., Ltd. is committed to continuous innovation to meet market demands and looks forward to esta  blishing long-term cooperative relationships with customers from both domestic and international markets.

FAQ

1.What is the expansion rate of the waterstop?

The volume can expand 200%-500% after water contact, with specific rates ranging from 150% to 600% depending on the model.

2.Can the color and size be customized?

Yes, colors like red and black are available, and other colors can be customized. Width and height specifications are also customizable.

3.How long is the delivery time?

The leading time is within 5 days for standard orders.

4.What warranty is provided?

We provide a 2-year warranty for all our waterstop products.

5.What certifications does the product have?

The product is certified with CE and complies with ISO9001 quality management standards.

6.Does the product offer self-healing capabilities?

Yes, it features self-healing capability to automatically repair new gaps caused by structural deformation.

7.What after-sales services are available?

We provide installation guides and professional technical assistance for construction guidance.