Every agriculture pipe carries a pressure class — typically 2.5, 4 or 6 kgf/cm². Farmers often buy on price alone, but matching the class to your pump and field layout is what determines whether the line survives.
What the number means
The rating is the continuous working pressure the pipe can safely carry. 1 kgf/cm² roughly equals the pressure of a 10-metre column of water. So:
- 2.5 kgf/cm² ≈ 25 m head
- 4 kgf/cm² ≈ 40 m head
- 6 kgf/cm² ≈ 60 m head
How to choose
2.5 kgf/cm² — gravity and light duty
Best for gravity-fed lines from canals or storage tanks, and short delivery runs from low-power pumps. It has the thinnest wall, so it's the most economical per metre.
4 kgf/cm² — the all-rounder
The most common choice for standard irrigation with 3–5 HP pumps and typical field distances. It balances wall thickness, durability and cost.
6 kgf/cm² — pumped and long-distance lines
Choose this when using higher-HP pumps, pushing water uphill, running long mainlines, or connecting sprinkler systems that need sustained pressure at the far end.
Don't forget surge pressure
When a pump starts or a valve slams shut, a pressure wave (water hammer) travels through the line — momentarily exceeding normal working pressure. This is why we recommend choosing a class above your calculated requirement if your system starts and stops frequently, and installing air-release valves at high points.
Matching fittings matter
A 6 kgf pipe joined with an under-rated fitting fails at the fitting. Use fittings from the same pressure family — couplers, elbows, tees, reducers and threaded adaptors — and the correct solvent cement applied on clean, dry surfaces.
Quick selection table
| Situation | Recommended class |
|---|---|
| Canal / tank gravity flow | 2.5 kgf/cm² |
| 3–5 HP pump, flat fields | 4 kgf/cm² |
| 5+ HP pump or uphill delivery | 6 kgf/cm² |
| Sprinkler mainlines | 6 kgf/cm² |
The BAISHALII ProFlo range
BAISHALII ProFlo Agri Selfit pipes are available in all three classes — 2.5, 4 and 6 kgf/cm² — with a complete family of matching fittings, all lead-free and made from virgin uPVC. Check the ProFlo page for size charts (from 63 mm to 160 mm) and product codes, or drop us an enquiry for dealer pricing.
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