Overview
The Irrimec OPTI RAIN ST6 is a water-powered turbine drive hard hose irrigator designed to deliver efficient, fuel-free irrigation across medium to large-scale agricultural operations. Manufactured by Irrimec in Italy, this hose reel irrigator harnesses water pressure to automatically rewind hoses ranging from 90 mm to 135 mm in diameter and up to 540 metres in length, providing reliable coverage without the need for external power sources or fuel. The turbine drive system converts the kinetic energy of the irrigation water into controlled mechanical rewinding motion, making it ideal for remote fields and operations seeking to minimise operating costs while maintaining consistent irrigation performance.
What distinguishes the OPTI RAIN ST6 within the turbine drive hard hose irrigator category is its robust gearbox-mounted turbine configuration and versatile hose capacity range that accommodates both mid-range and extended-length applications. The ST6 features a precision-engineered turbine flanged directly to a heavy-duty gearbox, ensuring reliable torque transmission and smooth hose retrieval across varying water pressures. Its galvanised steel chassis construction provides exceptional corrosion resistance for long-term field durability, while the integrated hose guide system ensures even winding and minimises hose wear. The platform design and wheel configuration offer stable operation across diverse terrain, and the built-in by-pass valve allows operators to fine-tune rewinding speed to match crop requirements and field conditions without interrupting irrigation cycles.
Key Features & Benefits
- Water-Powered Turbine Drive: Eliminates all fuel costs and electrical requirements by driving the rewinding mechanism entirely from irrigation water pressure, delivering true energy independence for remote paddocks and reducing operational expenses to zero for the drive system.
- Gearbox-Integrated Turbine: Turbine unit flanged directly onto the precision gearbox ensures efficient torque conversion and consistent rewinding performance across the full operating pressure range, minimising maintenance points and maximising reliability.
- Built-In By-Pass Valve: Allows precise adjustment of rewinding speed during operation by regulating water flow through the turbine, enabling operators to match travel speed to soil infiltration rates and crop water requirements without stopping the irrigation cycle.
- Extended Hose Capacity Range: Accommodates hose diameters from 90 mm to 135 mm and lengths from 250 metres to 540 metres, providing flexibility to configure the system for diverse field sizes, crop types, and irrigation patterns across your operation.
- Galvanised Steel Chassis: Heavy-duty hot-dip galvanised frame construction delivers superior corrosion resistance against constant water exposure and harsh field conditions, extending service life and preserving structural integrity for decades of reliable operation.
- Precision Hose Guide System: Engineered guide mechanism ensures consistent, even hose layering on the reel drum with each rewinding cycle, preventing overlap and uneven winding that cause premature hose wear and operational interruptions.
- Chain Drive Transmission: Robust chain-and-sprocket system transfers turbine power to the reel drum with minimal friction loss, providing smooth, controlled rotation and exceptional durability under continuous heavy-duty field use.
- Low-Maintenance Operation: Water-powered design eliminates engine servicing, fuel system maintenance, oil changes, and spark plug replacement, reducing annual maintenance hours and associated costs while improving field uptime.
- Silent Operation: Turbine drive produces minimal operational noise compared to engine-driven reels, making it suitable for noise-sensitive environments and improving operator comfort during extended irrigation monitoring.
- Stable Wheel Configuration: Purpose-designed cart and wheel arrangement provides secure positioning on slopes and uneven terrain while facilitating easy relocation between irrigation sets with standard farm tractors.
Technical Specifications
| Specification |
Details |
| Manufacturer |
Irrimec |
| Model |
OPTI RAIN ST6 |
| Product Type |
Turbine Drive Hard Hose Irrigator |
| Drive System |
Water-Powered Turbine |
| Turbine Configuration |
Gearbox-Flanged Turbine with Integrated By-Pass Valve |
| Transmission Type |
Chain Drive from Gearbox to Reel Drum |
| Hose Diameter Range |
90-135 mm (3.54-5.31 in) |
| Hose Length Range |
250-540 m (820-1,772 ft) |
| Maximum Hose Capacity |
540 m of Ø 90 mm hose (1,772 ft of 3.54 in hose) |
| Speed Control Method |
Adjustable By-Pass Valve for Flow Regulation |
| Raingun Compatibility |
Compatible with full range of travelling irrigation rainguns |
| Chassis Treatment |
Hot-Dip Galvanised Steel Construction |
| Wheel Configuration |
Heavy-Duty Agricultural Wheels with Stable Cart Platform |
| Hose Guide System |
Integrated Precision Guide for Even Hose Layering |
| Country of Manufacture |
Italy |
Available Hose Configurations
| Hose Diameter |
Hose Length |
Model Designation |
| Ø 90 mm (3.54 in) |
520 m (1,706 ft) |
90 TG |
| Ø 90 mm (3.54 in) |
540 m (1,772 ft) |
90 TG |
| Ø 100 mm (3.94 in) |
450 m (1,476 ft) |
100 TG |
| Ø 100 mm (3.94 in) |
480 m (1,575 ft) |
100 TG |
| Ø 100 mm (3.94 in) |
500 m (1,640 ft) |
100 TG |
| Ø 110 mm (4.33 in) |
370 m (1,214 ft) |
110 TG |
| Ø 110 mm (4.33 in) |
400 m (1,312 ft) |
110 TG |
| Ø 110 mm (4.33 in) |
450 m (1,476 ft) |
110 TG |
| Ø 120 mm (4.72 in) |
300 m (984 ft) |
120 TG |
| Ø 120 mm (4.72 in) |
350 m (1,148 ft) |
120 TG |
| Ø 120 mm (4.72 in) |
380 m (1,247 ft) |
120 TG |
| Ø 125 mm (4.92 in) |
300 m (984 ft) |
125 TG |
| Ø 125 mm (4.92 in) |
350 m (1,148 ft) |
125 TG |
| Ø 135 mm (5.31 in) |
250 m (820 ft) |
135 TG |
The OPTI RAIN ST6 series offers fourteen hose diameter and length combinations to match specific field dimensions, crop water requirements, and raingun specifications. Contact your irrigation specialist to determine the optimal configuration for your operating pressure, flow rate, and coverage area requirements.
Turbine Drive System & Operation
The OPTI RAIN ST6 employs a water-powered turbine system that converts irrigation water flow into controlled mechanical energy for automatic hose retrieval. As pressurised water enters the irrigator and passes through the turbine chamber, it spins the turbine rotor which is directly flanged to the precision gearbox. This gearbox reduces the high-speed turbine rotation to the optimal drum speed for smooth, consistent hose rewinding. The rewinding speed is directly proportional to water flow rate, creating a natural correlation between irrigation application and travel speed. A built-in by-pass valve allows operators to divert a portion of the water flow around the turbine, providing precise speed adjustment without interrupting the irrigation cycle or requiring the operator to return to the reel location.
This water-powered approach delivers significant operational advantages for agricultural irrigation enterprises. With no fuel consumption whatsoever, the OPTI RAIN ST6 eliminates recurring diesel or petrol costs and the logistical challenges of transporting fuel to remote field locations. The turbine system produces minimal operational noise compared to engine-driven alternatives, reducing operator fatigue and making it suitable for operations near residential areas or noise-sensitive environments. Maintenance requirements are dramatically reduced since there are no engines to service, no oil to change, no air filters to replace, and no spark plugs or carburettors to clean. Reliability is exceptional because turbine performance is tied directly to water pressure rather than mechanical engine components subject to wear and thermal stress. This makes the ST6 particularly valuable for operations in isolated paddocks without electrical infrastructure, where consistent irrigation performance must be maintained without dependence on external energy sources or frequent maintenance visits.
Ideal Applications
- Remote Fields Without Electrical Infrastructure: Water-powered turbine operation eliminates the need for electricity or fuel transport to distant paddocks, enabling reliable irrigation in locations where engine servicing and fuel logistics are impractical or cost-prohibitive.
- Pasture and Forage Production: Cost-efficient operation and long hose runs make the ST6 ideal for irrigating extensive pasture areas where minimising per-hectare irrigation costs is essential for profitable livestock grazing operations.
- Row Crops and Broadacre Field Crops: Consistent rewinding speed and uniform water application across extended irrigation runs suit cereals, oilseeds, pulses, and row crops requiring precise moisture management during critical growth stages.
- Sports Turf and Recreational Fields: Quiet turbine operation and smooth hose retrieval make the system suitable for golf courses, sports grounds, and parks where irrigation must occur with minimal noise disruption and no fuel odours.
- Organic Farming Operations: Zero fuel consumption and absence of engine emissions align with organic certification requirements and sustainability commitments, while eliminating the risk of fuel or oil contamination of certified organic land.
- Nurseries and Horticultural Operations: Precise flow-controlled rewinding speed allows careful irrigation of high-value nursery stock and vegetable crops where consistent moisture levels and gentle water application are critical for crop quality.
- Supplementary Irrigation for Dryland Farms: Low capital and operating costs make turbine drive hard hose irrigators economically viable for occasional supplementary irrigation during dry periods, protecting crop yields without the investment required for permanent irrigation infrastructure.
