Irrigation
Runte TOLV 4 L/h Anti-Drip Emitter
The Runte TOLV is a black, high-pressure anti-drip emitter rated at 4 L/h. In April 2026, 30 samples were tested to GB/T 19812.2–2017 across a working pressure of 50–350 kPa. The report gives a mean flow deviation of −3.50%, a coefficient of variation of 1.81% and a flow exponent of 0.04. Those figures describe how close the samples came to 4 L/h, how much they varied and how little flow moved with pressure. Before ordering, ask Runte for the emitter's code and connection drawing, its anti-drip opening and closing pressures, and confirmation that the build you buy matches the tested samples.
Ningbo Runte Irrigation Equipment ↗
Build my procurement briefWhat the three flow results tell you
The report gives three separate results. Each answers a different question about the samples, so compare them one by one with the figures other suppliers quote.
| Result | What it measures |
|---|---|
| Mean deviation −3.50% | The average flow of the samples sat 3.50% below 4 L/h under test conditions. Individual emitters and other pressures or temperatures can differ. |
| Variation coefficient 1.81% | How much flow varied from one sample to the next. In the field, pipe losses, height differences, dirt and fitting quality add to that. |
| Flow exponent 0.04 | How much flow changed as pressure changed during the test. Close to zero means strong compensation within the tested range. |
Sources [3]
Published specifications
Read each value with its stated conditions, and ask the manufacturer for any limit not listed here.
| Specification | Published value | Meaning / limit |
|---|---|---|
| Tested emitter | TOLV high-pressure anti-drip emitter; black; 4 L/h [1] [3] | Name as given in the report. Ask for the current SKU and drawing revision. |
| Samples tested | 30 [3] | The number of emitters in the test. |
| Working pressure | 50–350 kPa [3] | The range listed for the 4 L/h samples. The curve plots a wider axis; use the listed range. |
| Mean flow deviation | −3.50% [3] | Average sample flow compared with the 4 L/h rating. |
| Coefficient of variation | 1.81% [3] | Spread of flow between samples in the test. Field uniformity also depends on your pipe layout. |
| Flow exponent | 0.04 [3] | How strongly flow follows pressure. A low figure means flow changes little with pressure. |
| Test dates and standard | 2–8 April 2026; GB/T 19812.2–2017 referenced [2] [3] | Commissioned test on samples Runte sent in. Ask for the original report if you need it for acceptance. |
Working pressure and the test curve
The results page lists a working pressure of 50–350 kPa for the 4 L/h samples and plots a pressure-flow curve on a wider axis. Design to the listed range.
Ask Runte for the pressure and temperature limits of the build it quotes, and the band over which the stated compensation holds. Give your designer the real emitter pressures, elevation and supply variation. The RT catalogue drippers carry their own pressure figures; ask Runte whether any RT model shares the TOLV results.
Anti-drip function and shutdown
The emitter is sold as anti-drip, but the test results cover flow and pressure compensation. If you need the line to stay full after shutdown, or restart evenly, ask Runte for those figures separately. If you would rather empty the laterals when watering stops, a fitting such as the Rain-Ling automatic drain valve does that job instead. Emitters from other makers in the irrigation category can be held to the same request.
Opening and closing pressure
Ask at what pressure the emitter opens and closes. The 50 kPa lower working limit is a different figure.
Drain-down and restart
Describe the elevations and how the system will shut down and restart, and ask for test data on residual drainage.
Connection and mounting
Ask for tube size, barb dimensions and allowed mounting position, and whether it is supplied as an arrow-dripper kit.
Water and maintenance
Give your water and fertiliser details, and ask for filtration, cleaning and replacement instructions and chemical compatibility.
Matching the tested samples to your order
The cover and both report pages name Runte, and the Chinese company introduction lists TOLV pressure-compensating drippers as a core product. Ask Runte to tie the tested samples to the emitter it quotes by code and drawing revision.
| What the report shows | What to ask in the quotation |
|---|---|
| Samples sent by Runte | Ask how the samples relate to current production and which inspection records will cover your lot. |
| Black, 4 L/h | Confirm the flow version, code, drawing and parts. Colour and nominal flow alone leave the internal build open. |
| Original report | Ask for the original documents and a way to confirm them with the testing centre if you use them for acceptance. |
| Other Runte models | RT-8070 and RT-8300 have their own catalogue entries. Ask Runte in writing whether the TOLV results apply to any of them. |
From 4 L/h to a working line
A 4 L/h rating becomes a design once you know the number of emitters, the layout and the operating conditions. Give your designer or Runte the outlet count, the water each plant needs, the supply, the pipe and elevation layout and the controls. Lateral length, watering time and water saving come out of that design. Our guide to specifying irrigation hose and pipe covers the drip side of that work, from inner diameter to friction loss.
To compare in the field, agree the setup, pressures, water and sampling method first, then measure flow and drainage and record which assembly was used. Keep those field readings apart from the April 2026 sample results. Take the trial method and pass criteria from Runte's instructions or your designer's specification.
Buyer questions
Is the flow exactly 4 L/h at any pressure?
Within 50–350 kPa the test found a flow exponent of 0.04, so flow changes very little. Ask Runte for the compensation and operating limits of the build you buy. [3]
Does 1.81% mean 98.19% field uniformity?
No. 1.81% is the coefficient of variation between test samples. Field uniformity has to be measured on your system. [3]
Is 50 kPa the anti-drip closing pressure?
50 kPa is the bottom of the working range. Ask Runte for the opening and closing pressures. [3]
Prepare a model-specific brief
Write your actual conditions below. This local worksheet is not sent, uploaded or saved after reload. Copy or print it before leaving.
Sources
Specifications come from the manufacturer's publications listed below, with the date each was checked.
- Hosted TOLV test-report cover
manufacturer · Checked 2026-10-11
Cover of the commissioned report naming Runte and the TOLV high-pressure anti-drip dripper, dated April 2026.
- Hosted report page 1 of 2
manufacturer · Checked 2026-10-11
Applicant details and Guangcheng building 11, received 1 April 2026, test on samples sent in by Runte, GB/T 19812.2–2017.
- Hosted report page 2 of 2, sample results and pressure-flow curve
manufacturer · Checked 2026-10-11
Black 4 L/h, 30 samples, tested 2–8 April 2026, 50–350 kPa; mean deviation −3.50%, coefficient of variation 1.81%, flow exponent 0.04.
- Official Chinese TOLV range statement
manufacturer · Checked 2026-10-11
Company introduction naming TOLV pressure-compensating drippers as a core product.
Report a correction through our contact form, quoting Runte TOLV 4 L/h Anti-Drip Emitter and the relevant specification.