Woven polypropylene · filled on site · sourced in China
Tubes and bags for river banks, shorelines and sludge dewatering. A tube tears at the seam, not in the cloth, so every grade we quote carries its seam strength and pore size, and we test both on your batch before you pay the balance.
The lines a tender is judged on
Class 1 sheet: 2.3–18 m circumference, fill ports 30 or 45 cm. Larger dewatering tubes, tube lengths and bag sizes are sewn to your drawing.
Where geotubes fail
A geotube is not a fabric. It is a container sewn from fabric and filled in place: with sand or dredged silt pumped from a dredger, or with sludge for dewatering. The fabric holds the fill and lets the water through. So the product has exactly two weak points, and neither of them is described by the grams per square metre that most quotes compete on.
The first is the seam. The pump drives slurry in under pressure and the whole load lands on the long seam, even when the fabric is flawless. The second is the pores. Too open, and the fines leave with the water, the tube settles and never reaches its design height. Too tight, and the fabric blinds, the filtrate stops, and every filling cycle drags on.
That is why every XILINK quote shows both lines for each grade, and why those two are what we test on your batch. A mill that cannot show a seam test report has already answered the question.
Failure 01
The seam
Factory seam strength · EN ISO 10321 or ASTM D4884
On the batch certificate further down this page, the seam held about two thirds of what the fabric beside it did. Check this line against your tender clause in the same test method: an EN ISO 10321 value and an ASTM D4884 value are not interchangeable. A cheap quote usually leaves this line out.
Failure 02
The pores
Opening size O90 · EN ISO 12956, or AOS by ASTM D4751
Matched to your fill: pumped sand, dredged silt and flocculated sludge are three different jobs. Next to O90 we always read the flow: 15–20 l/m²/s by EN ISO 11058, or 240 l/min/m² by ASTM D4491. It decides how many filling cycles a tube gives you per shift.
Which job
Geotube and geobag are the same woven fabric in five different roles. Name the job first; the job tells you which number in the grade tables below matters most for you. The filter layer underneath is a separate item, see woven and nonwoven geotextile.
| Job | What goes in | What decides the choice |
|---|---|---|
| Bank toe and groyne core | Tubes filled by pumping at the toe of the slope, or as the core of a groyne | Tensile strength and seam strength to survive filling; O90 matched to the fill sand |
| Bed and falling apron | Sand-filled geobags placed under water in layers | Seam strength; a UV grade if the bags wait in the open before placing. Bag weight is a design input, not a quality mark |
| Breakwater, dune and headland core | Stacked tubes as a temporary breakwater, a headland or a dune core, later covered | Tensile strength, strength kept after UV, and puncture resistance |
| Dredging and silt dewatering | Sediment from rivers, lakes, reservoirs and ports, pumped into tubes on a prepared pad | O90 and flow rate for clean filtrate; tube circumference and fill height |
| Sludge dewatering | Municipal and industrial sludge, farm effluent, mine tailings and wash slurry, dosed with flocculant | O90 and flow rate; seam strength at filling pressure; number of fill ports |
How a tube is filled
The same four steps whether the fill is dredged silt or treated sludge. Watch one dewatering run from start to finish, then read what each step asks of the tube.
Level it and lay a filter and drainage layer sloped to a ditch. Keep the top of the drainage layer flat so the tube cannot roll. Many sites line the pad with an HDPE liner first.
Pump through the fill ports in stages, with pauses: the filtrate drains, the fill consolidates, then the next lift goes in.
For sludge the chemical is dosed into the line before the tube. Without it the filtrate runs cloudy and each cycle takes longer.
Fill the centre tube first and work outwards, so the row closes up tightly.
Grades and properties
Below is what the mills actually ship: two woven polypropylene grades tested to EN ISO methods (HS60 and 400 g/m²), and a Class 1 tube tested to ASTM methods for exposed shorelines, fast rivers and long filling runs. If your tender names one of these systems, we agree the test regime before the order is placed, not after.
Class 1 comes in 2.3 / 4.6 / 6.8 / 9.1 / 14 / 18 m circumference with 30 or 45 cm fill ports. Tube length, the circumference of the EN ISO grades and geobag sizes are sewn to your drawing and confirmed in the mill order, not taken from a catalogue. We work out the container plan before we quote, so the delivered price per piece is a figure, not an estimate.
Technical data sheet · PDF · 2 pages
Attach it to your tender file or send it to your engineer.
Grade HS60 (≥ 300 g/m²) and grade 400 g/m² · bank protection, aprons, dewatering
Swipe sideways to see the test methods
| Property · unit | HS60 | 400 g/m² | Test method |
|---|---|---|---|
| Mass per unit areag/m² | ≥ 300 | ≥ 400 | EN ISO 9864 |
| Thicknessmm | 0.65 | – | EN ISO 9863 |
| Tensile strength at maximum load MD / CDkN/m | ≥ 60 / ≥ 45 | ≥ 90 / ≥ 90 | EN ISO 10319 |
| Elongation at maximum load MD / CD% | ≤ 25 / ≤ 15 | ≤ 10 / ≤ 10 | EN ISO 10319 |
| Tensile strength at 2 % strain MD / CDkN/m | – | ≥ 25 | EN ISO 10319 |
| Tensile strength at 5 % strain MD / CDkN/m | – | ≥ 70 | EN ISO 10319 |
| Tear strength MD / CDkN | ≥ 0.9 / ≥ 0.6 | – | EN ISO 13937-1 |
| Factory seam tensile strengthkN/m | ≥ 70 | ≥ 60 | EN ISO 10321 |
| CBR puncture resistancekN | 6 | ≥ 10 | EN ISO 12236 |
| Dynamic perforation (cone drop), hole diametermm | 12 | ≤ 12 | EN ISO 13433 |
| Characteristic opening size O90mm | 0.3–0.5 | ≥ 0.45 | EN ISO 12956 |
| Water permeability normal to the planel/m²/s | 15–20 | ≥ 15 | EN ISO 11058 |
| UV resistance, 500 h, strength retained% | ≥ 90 | – | EN ISO 13438 |
| UV resistance, 500 h, strength retained% | – | ≥ 85 | ASTM D7238 |
Exposed shorelines, fast rivers, long filling runs · circumference 2.3–18 m
Swipe sideways to see test method and frequency
| Property · unit | Value | Test method | Test frequency |
|---|---|---|---|
| Tube circumferencem | 2.3 / 4.6 / 6.8 / 9.1 / 14 / 18 | Measured | n/a |
| Fill port diametercm | 30 or 45 | Measured | n/a |
| Wide-width tensile strength MD × CDkN/m | 175 × 175 | ASTM D4595 | 7,500 m² |
| Wide-width elongation (max.) MD × CD% | 15 × 15 | ASTM D4595 | 7,500 m² |
| Trapezoidal tear strength MD × CDkN | 2.7 × 2.7 | ASTM D4533 | 7,500 m² |
| Puncture strengthkN | 1.8 | ASTM D4833 | 7,500 m² |
| Seam strength (factory)kN/m | 105 | ASTM D4884 | 40,000 m² |
| Apparent opening size (AOS)mm | 0.425 (max.) | ASTM D4751 | 40,000 m² |
| Water flow ratel/min/m² | 240 | ASTM D4491 | 40,000 m² |
| Accelerated UV resistance, strength retained after 10,000 light hours% | 65 | ASTM D7238 | formulation |
MD = machine direction (along the roll), CD = cross direction. ≥ is the minimum and ≤ the maximum the mill specifies; a value without a sign is the mill's typical result. “–” means the mill's sheet for that grade does not report the property: ask, and we test your batch. HS60 is the mill's grade code (60 kN/m in MD); the 400 g/m² grade is designed to meet GRI-GT13(b), ISO version. Class 1 table: all values are minimum average values unless noted otherwise; property set and test frequencies follow GRI Test Method GT10, and “7,500 m²” means one test per 7,500 m² of fabric produced for your order. Polypropylene resists naturally occurring soil acids and alkalis and is unaffected by bacteria and fungi.
What real orders cost
US$1,500–2,400 per tube, at the mill
Dewatering tubes of 28 m circumference, 30 to 55 m long, woven PP 105 × 105 kN/m, on our 2023 and 2024 orders for a buyer in Kazakhstan. The longer the tube, the higher the price. Polypropylene prices move, so treat this as a benchmark and ask for today's figure: we quote per piece, with the freight to your destination port on its own line.
Before the balance is paid
The mill's sheet describes a grade. Your batch is one particular roll, one sewing line and one set of fill-port sleeves, and that is where the gaps appear. So our acceptance of geotubes runs on the two numbers from this page, seam strength and O90, plus a look at the seam rows and fill-port sleeves before loading. Next to this text is the certificate from one real batch.
XILINK is an export and sourcing company based in Jinan, operating since 2012. We are not the mill; we are your checking side in China. Lab sheets and inspection photos reach you before the balance payment: the leverage first, then the money.
Batch certificate · one real order
28 m circumference × 30 m, woven PP 105 × 105 kN/m. Produced 21 August 2023, tested the next day to ASTM methods.
Copied line by line from the mill's certificate of analysis; issuer, batch number and signatures are left off here. Your batch comes with the same certificate before the balance is paid.
With every batch
Straight answers
Size and how it is installed, not the fabric. A geotube is a long container filled in place by pumping through fill ports: 2.3–18 m in circumference on the Class 1 sheet, and larger for dewatering (the tubes on this page were 28 m). A geobag (geocontainer) is smaller; it is filled with sand and placed under water in layers, often from a barge. The fabric is the same, but for the tube the seam has to survive filling, and for the bag it has to survive the drop to the bed.
The one your design needs, and always with its test method. By EN ISO 10321 the grades on this page give ≥ 70 kN/m (HS60) and ≥ 60 kN/m (400 g/m²); by ASTM D4884 the Class 1 tube gives 105 kN/m. If your tender clause is written in the other system, tell us early: the test regime is agreed before the order is placed, not after shipment.
Each grade has its own value on the mill's sheet: O90 0.3–0.5 mm for HS60 and ≥ 0.45 mm for the 400 g/m² fabric (EN ISO 12956), AOS 0.425 mm max. for the Class 1 tube (ASTM D4751). You pick the grade by the fill, because pumped sand, dredged silt and flocculated sludge behave differently. Send a description of the material and, if you have it, the grading curve: we match the grade's pore size and flow rate together with the tube circumference.
For sludge, yes: the chemical is dosed into the line before the tube, otherwise the filtrate runs cloudy and the cycle drags on. For dredged silt it depends on what the sediment is. We do not promise dewatering times without knowing your material: filling always runs in lifts with pauses to drain, and the number of cycles per shift depends on the fabric's flow rate and the number of fill ports.
The standard Class 1 range is 2.3 / 4.6 / 6.8 / 9.1 / 14 / 18 m, with 30 or 45 cm fill ports; dewatering tubes are often larger, like the 28 m tubes on this page. Circumference sets the fill height, that is, the level you build up to. Tube length, the circumference of the EN ISO grades and geobag sizes are sewn to your drawing. The order needs the job, the fill material, the sizes, the number of pieces and the destination port.
A quote for your job
Tell us the job (bank toe, apron, breakwater or dewatering) and the fill. You get back the fabric grade, seam strength and O90 by your tender's test method, the sizes, and a price delivered to your site. Usually within one working day.
To quote, we need four things