Specifying Irrigation Hose and Pipe: Lay-Flat, Suction, Rain-Spray and Drip

Four kinds of line, four different jobs

Hose and pipe make up a large share of any irrigation order, and the four common types do quite different work. Lay-flat hose carries water from the pump to the field and rolls up afterwards. Suction hose feeds the pump inlet and must hold its shape under vacuum. Rain-spray hose is a perforated lay-flat line that waters a strip of crop at low pressure. Drip lines deliver small, measured amounts of water at each plant through emitters.

Specify each one against the same three questions: what pressure (or vacuum) it will see, what flow it must carry over what length, and what water quality it will handle. The answers decide inner diameter, wall or reinforcement, and the fittings you need from the wider range of irrigation equipment.

Working pressure and burst pressure

Hose datasheets usually print two pressures. Burst pressure is the short-term pressure at which a sample fails. Working pressure is the lower figure to design to. Kuriyama's data for its 2-inch Vinylflow PVC lay-flat discharge hose, for example, lists 65 psi working and 195 psi burst, both stated at 68°F (20°C), so burst is three times the working rating on that sheet [3]. The same listing describes the hose as an open-end water discharge hose and gives a service range up to 140°F (60°C) [3].

So when you compare PVC lay-flat hose from different suppliers, ask for both numbers, the ratio between them and the temperature at which they were measured. Two hoses with the same printed burst pressure can carry different working ratings. Size the working pressure above the pump's shut-off head, because a closed valve at the far end of the line lets the pump reach that figure. Ask also about the reinforcement yarn, the cover material and UV protection if the hose will lie in the sun all season.

Suction hose: vacuum and temperature

A suction hose has a rigid helix moulded into the wall so it does not collapse when the pump draws water. Its datasheet should give a vacuum rating as well as a pressure rating. Kuriyama's heavy-duty PVC suction hose with a rigid PVC helix, for instance, is listed at full vacuum at 20°C and both its pressure and vacuum figures are lower at 40°C [4]. Expect the same pattern from any PVC suction hose, including the NTS-101GS, and ask for the ratings at your hottest working temperature.

Keep suction lines short and generous in diameter. On the inlet side, friction losses add directly to the lift the pump must achieve, and a suction pipe larger than the discharge pipe is the standard recommendation [5]. Specify a foot valve and strainer with the hose, and check that the couplings seal against air, since a small leak on the suction side stops a centrifugal pump from priming [5].

Inner diameter and friction loss

Every metre of hose, every fitting and every valve takes some pressure from the water. Extension engineers count this as friction head and add it to the lift and the outlet pressure when working out the total the pump must supply [5]. One psi equals about 2.31 feet of head [5], so a line that loses 0.5 bar along its length has used about 5 metres of the pump's head before any water reaches a sprinkler.

Friction grows quickly as flow rises in a given bore, so the cheapest way to win back pressure is often a larger inner diameter on the long main run. Ask suppliers for inner diameter rather than nominal or flat width, and for friction loss per 100 metres at your flow if they publish it. The same logic applies to tees, a pipe saddle or a compression coupling: count each one, and pick fittings with a full bore where the flow is high. A double-union ball valve at each zone lets you isolate and service a section without cutting the line.

Rain-spray hose

Rain-spray hose is laid along a bed and sprays from rows of small holes. Its throw width and the length you can run from one feed depend on the inlet pressure, the hole pattern and the hose width. When you compare the normal and double-wing rain-spray hose types, or a model such as the NPD-102PD, ask for spray width at a stated inlet pressure, the recommended maximum run length, the hole spacing and the flat width. Where many lines branch off one header, a prefabricated-hole main pipe saves drilling and keeps the take-offs evenly spaced.

Drip lines and emitters

Drip products fall into three families. Thin-walled drip tape for seasonal crops spans roughly 4 to 35 mil of wall, emitter spacing from 2 to 36 inches and emitter flows of about 0.07 to 0.84 gallons per hour. Drip tubing with in-line emitters has thicker walls, around 23 to 47 mil, for perennial crops. Hard hose with punch-in emitters is common in nurseries and landscapes [1]. Wall thickness decides how many seasons the line lasts and how much handling it tolerates.

Pressure-compensating emitters deliver the same flow across a working pressure band, which keeps output even on long laterals and slopes. Netafim's technical sheet for one such dripper line shows the details to ask for: the compensating range, a shut-off pressure for the anti-drain version, a recommended filtration of 130 micron or 120 mesh, and a maximum working pressure that rises with wall thickness [2]. Below its minimum pressure a compensating dripper behaves like an ordinary one [2]. When you compare the RT-8070 drippers or an anti-drip emitter, ask for the same set of figures and the ISO 9261 test basis.

Filtration and vacuum protection come with the system. Filters should remove particles about four times smaller than the emitter opening, and surface water needs filtration to about 200 mesh [1]. A pressure-control valve sets the line pressure, and an air vent between the solenoid valve and the drip lines stops soil being drawn into emitters when the system shuts off [1]. Air-release valves, an automatic drain valve and a zone valve such as the Yilin YL28009-3 or the EVA/EVD solenoid valves complete the layout. A flow meter on each zone, read daily, shows leaks and clogging early [1].

Putting the order together

Send each supplier a simple line list: type, inner diameter, length per roll, working pressure at your temperature, vacuum rating for suction lines, emitter flow and spacing for drip, and the fittings at each joint. Ask for the datasheet behind each rating.

Makers to compare include Hangzhou Neetrue Irrigation Facilities for lay-flat, suction and rain-spray hose; Ningbo Runte Irrigation Equipment for emitters; Ningbo Airuiteke for fittings; RAIN LING and Ningbo Yilin Water Saving Technology for valves; Ningbo Dewo Irrigation Equipment for sprinklers; and Ningbo Meizhi Tools and Ningbo Yangteng for garden-scale watering, such as a metal hose nozzle or a dual-outlet watering timer.

Source notes

[1] Oregon State University Extension Service — Drip Irrigation: An Introduction (EM 8782), C. C. Shock (2013 (revised March 2013)) [2] Netafim — UniGray CNL & HCNL Technical Product Sheet (2019) [3] Kuriyama of America — Vinylflow EZ-Lite PVC Layflat Water Discharge Hose, series VFL200X50 (product data) (2026 (accessed 2026-11-04)) [4] Kuriyama of America — S Series Heavy-Duty PVC Suction Hose (S100X100) product data (2026) [5] NDSU Extension (North Dakota State University) — Irrigation Water Pumps (AE1057), T. F. Scherer (2022 (reviewed February 2022))