Lay flat hose: the complete guide to types, pressure, sizing and couplings

Few hoses do as many jobs as lay flat. The same basic construction carries floodwater off a construction site, frac water between ponds and well pads, a submersible pump’s output up a 200 m borehole, diesel to a drilling camp, drinking water to a relief site and liquid manure across a farm. What changes from job to job is the cover material, the pressure class, the bore and the coupling — and choosing those four correctly is most of the work.

/01What lay flat hose is.

Every lay flat hose has three layers. The jacket is a seamless tube of polyester yarn woven on a circular loom; it carries the internal pressure and, when the hose hangs in a well or is dragged behind a tractor, the tensile load. The tube on the inside seals the fluid in and decides chemical resistance. The cover on the outside takes abrasion, sunlight and weather.

How the layers are joined matters more than any single material. In through-the-weave construction the polymer is extruded through the woven jacket in one pass, so tube, jacket and cover become one wall that cannot delaminate. All of our TPU lay flat hoses are made this way. Older lined hoses glue a separate tube inside the jacket; they work, but the bond is the first thing to fail when the hose is flexed, heated or dragged for years.

/02Where it is used.

Lay flat replaces rigid pipe wherever a line has to go down quickly, move often or come back up again. These are the applications we supply it for, and the hose built for each:

Links to each: TPU dewatering hose, NBR discharge hose, TPU well riser hose, antistatic fuel hose, drinking water hose, concrete placement hose, slurry supply and slurry drag hose, jacketed fire hose and PVC lay flat hose.

/03TPU, nitrile rubber or PVC.

The cover material sets almost everything else — pressure class, abrasion life, oil resistance, temperature range, weight and price. In short:

Our TPU vs NBR vs PVC comparison goes through each property in detail, with the trade-offs that decide most orders.

/04What the pressure rating means.

Lay flat hose carries two pressure figures. The working pressure is the most it may see in service; the burst pressure is a test figure — usually two to three times the working pressure — and never an operating limit. The working pressure also falls as the bore grows, because the same jacket has to hold a larger circumference. Our TPU dewatering hose shows the pattern:

Different products are built to different classes: the TPU well riser hose runs from 40 bar at 1-1/4" to 18 bar at 10", the high-pressure class of concrete hose reaches 85 bar, and the NBR discharge hose is 10 bar in every size. Our guide to lay flat hose pressure ratings explains why, and how to allow for surge and couplings.

/05Sizing a line.

Pick the bore from the flow and the length of the line, not from the pump outlet. Pushing water through a hose costs pressure — friction loss — and the loss climbs steeply as the bore shrinks. As a rule of thumb, keep the water speed between about 1.5 and 3 m/s. At 200 m³/h a 6" line loses roughly 4.6 bar per kilometre; a 4" line at the same flow loses over 30 bar per kilometre, more than the hose can carry.

Then add the static head: every 10 m the water is lifted costs about 1 bar. The friction loss plus the lift plus any delivery pressure must stay inside the working pressure of the hose and of every coupling on it. The full method, with a loss table for every bore from 2" to 16", is in our guide to lay flat hose flow and friction loss.

/06Couplings and handling.

A lay flat line is only as good as its joints. Small bores take cam and groove, Storz or Bauer-type couplings banded onto the hose. From 4" up, purpose-made lay flat couplings use a forged shank and bolted clamp halves, ending in a grooved end, a large Storz head, a flange or a high-pressure male and female pair. Our coupling guide compares them.

Handling is the other half of the economics. A 16" hose weighs 6.2 kg per metre, so a 200 m length is more than a tonne: it needs a tractor-mounted reel, a portable motorised winder or a hose mover. Borehole risers go in and out with a powered winding trailer.

/07The one job it cannot do.

Our EPDM/PE suction hose has a rigid polyethylene helix and is rated for vacuum at every size from 1" to 6". The guide to suction hose vs lay flat hose shows how to lay out the two sides of a pump.

/08Choosing in five questions.

In the Gulf, lay flat does most of its work in a handful of jobs: construction dewatering on high-water-table sites, frac water transfer to gas well pads, flexible risers in boreholes, temporary fuel lines and fire hose. Each has its own guide, and running lay flat in Gulf heat covers what summer does to all of them.

In Europe the same hose turns up in very different work: slurry umbilical systems on farms, over-pumping and water main bypass, flood response, mine dewatering, snowmaking, irrigation and concrete placement.

Practical references: the lay flat hose size chart, how to roll and store lay flat hose, how to repair it, and the RFQ checklist for ordering.