Anping County, Hengshui Hydrophilic Swelling Waterstop Strip Supply – Custom Sizes, Lead Time and Technical Support

Published on 2026-10-17

Hengshui Zhanhe Engineering Rubber Co., Ltd. supplies hydrophilic swelling waterstop strip and related engineering rubber products to contractors, distributors and infrastructure projects worldwide. A strip fixed to the hardened concrete face before the next pour. When water reaches it the strip swells and presses into the interface, closing the gap that fresh concrete cannot fill by itself.

This article explains the working principle, main types, typical applications, installation points, selection criteria, standards and frequently asked questions about hydrophilic swelling waterstop strip, and is intended for engineers, purchasers and project managers.

1. What Is Hydrophilic Swelling Waterstop Strip?

A strip fixed to the hardened concrete face before the next pour. When water reaches it the strip swells and presses into the interface, closing the gap that fresh concrete cannot fill by itself.

Working principle: The product works through elastic deformation and mechanical interlock to provide reliable sealing or load transfer.

2. Main Types

• Mastic type (BW): butyl based, soft and shapeable, suits uneven surfaces
• Vulcanised type (PZ): higher swelling ratio and stable performance under repeated wet-dry cycles
• Strip with an integral injection hose for later grouting
• Slow-swelling type with a surface coating for rainy weather or uncertain schedules

3. Typical Applications

• Horizontal construction joints in basement walls
• Ring and longitudinal joints of shield tunnel segments
• Joints between precast utility tunnel elements
• Details such as pipe sleeves, pile heads and post-poured strips

4. Installation and Construction Points

1. Roughen and clean the joint face, removing laitance, oil and standing water
2. Cut to length, fold or mitre at corners with an overlap of at least 50 mm
3. Fix with adhesive or nailed washers at 200-300 mm spacing, fully bedded without lifting
4. Where pouring may be delayed or rain is likely, use the slow-swelling type and cover the strip
5. Keep the poker vibrator away from the strip during concreting
6. Check the joint line after striking the formwork and keep photographic records of the hidden works

5. Selection Guide

• Confirm the design displacement, load grade and service environment before ordering.
• Select material grade according to temperature range, medium and durability requirements.
• Provide drawings or a specification list so that the manufacturer can verify sizes.

6. Standards and Quality Control

Hydrophilic Swelling Waterstop Strip is manufactured and inspected according to applicable national and industry standards. Hengshui Zhanhe Engineering Rubber Co., Ltd. carries out batch inspection before delivery, and inspection certificates together with third-party test reports (where required by the project) can be provided.

Typical standards applied to this product family include Chinese national and transportation industry standards; equivalent international standards can be referenced upon request.

7. FAQ

Q: Is a higher swelling ratio better?

A: Not necessarily. A 600% product generates high swelling pressure, loses swelling agent after repeated wet-dry cycles, and can even crack weak concrete. Around 220%-300% suits most work; above 400% is reserved for high heads or wide gaps.

Q: Can it be applied to a damp surface?

A: Slight dampness is acceptable but standing water is not, because it triggers premature swelling and weakens the bond. In wet weather choose the slow-swelling type and keep the strip covered until the pour.

Q: How does it work together with a steel plate or an embedded waterstop?

A: The mechanisms complement each other: the steel plate lengthens the water path, the waterstop seals elastically, and the strip fills the interface by swelling. Horizontal joints often use a plate plus the strip, vertical joints a waterstop plus the strip. The strip is an added line of defence rather than a stand-alone one.

Q: How should it be accepted and stored?

A: Inspect each batch for blisters, contamination and section size, check the certificate and test report, and sample-test the swelling ratio and water resistance. Store in a dry, shaded place, protected from rain, and avoid heavy stacking on the mastic type.

8. Price Factors

Priced per metre. Cost depends on the compound formulation, the section size and whether an injection hose is included. A standard 20x30 mm mastic strip is commonly quoted at 6-15 yuan per metre; the vulcanised type costs more because of the extra curing step, and the hose version adds tube and connector costs. Order the length plus about 5% for laps and waste.

Packing: standard export packing (woven bags, pallets or wooden cases). Delivery terms: EXW, FOB, CFR, CIF or DAP as agreed. Payment terms: T/T, L/C or other terms subject to negotiation.

9. Why Work With Hengshui Zhanhe Engineering Rubber Co., Ltd.

• Manufacturer based in Hengshui, Hebei — the engineering rubber industry cluster in North China, with in-house production and inspection.
• OEM and ODM supported: sizes, hardness, profiles and packaging can be customized to project or market requirements.
• Batch inspection before shipment; certificates of conformity and third-party test reports available when required.
• Technical support for selection, shop drawings and installation guidance, with export packing and worldwide logistics arrangement.

10. Contact and Quotation

For specification sheets, samples, pricing or project support, please contact Hengshui Zhanhe Engineering Rubber Co., Ltd.. Email: 150051331@qq.com · Tel/WhatsApp: +86-13833886677 · Factory: No.168, Zhangtuantuo Village, Dengzhuang Town, Taocheng District, Hengshui, Hebei, China. We reply to export enquiries within 24 hours on working days.