THE development of the Harrington Seed Destructor (HSD) continues to change the way WA growers manage weed seeds.
Last week the Harrington family, CGS Engineers mechanics, Australian Herbicide Resistance Initiative (AHRI) representatives and University of South Australia engineers, assessed three HSD models in a Wagin paddock to make modifications.
University of South Australia research engineer Chris Saunders, who has worked on the GRDC-funded project since June 2009, said one of the most fundamental modifications made since Ray Harrington's initial design was the chaff transfer system.
"Since then we've been involved in looking at how much fuel its using, how much power its using and all aspects of its design," he said.
A system was designed with sensors so the parameters of the machine could be logged and recorded, including power, engine speed and airflow.
During the trials at Wagin last week data was logged and then analysed by Mr Saunders and the university team.
"Global positioning systems are also fitted so we know where the machine is in the paddock and we interrogate the information afterwards," Mr Saunders said.
"From the data logging measurements we're able to learn a lot about how the system's working and that's how we looked at the chaff transfer system and evolved it to version three.
"Basically Ray's original system had an auger in the transfer system and the material was flowing above the auger.
"The computer modelling we did showed that you get a very turbulent flow and its not ideal for pneumatically conveying material so we've done away with the auger and that's what we're testing today."
Pneumatic conveyance had been used in the agricultural industry for a long time and continues to be used on air seeders today.
"The system is more scalable and by using this system we can scale it up to a larger capacity to suit larger headers," Mr Saunders said.
"Once we can do that we'll really see if the mill has the capacity for larger-sized headers."
Mr Saunders thought the HSD had the potential to suit large headers throughout WA's Wheatbelt region.
"The monitoring we're doing now shows we're only using 50 to 70 per cent of the engine's power," he said. "So there's power in reserve.
"We don't think the mill is at its full capacity because the header we're using can't actually fill it at this stage."
The testing was done in a barley crop which had suffered from the dry season and further development by both the AHRI, the GRDC and the University of South Australia is needed to see the effects on different grain types.
"Ray has tried the HSD on everything at home but the monitoring done, even just today, has taught us a lot about how those systems work and we've been able to improve its design and performance," Mr Saunders said.
A test of the HSDs in June last year uncovered a problem with a baffle design in the harvester which restricted airflow and meant a really poor sample was produced.
During the recent tests the baffle was modified, ryegrass seeds were put through the harvester, collected in the outgoing chaff and counted.
"With the baffle in one position we put 20,000 ryegrass seeds in the front of the header and 100 got through the HSD," Mr Saunders said.
"We changed the position and only got 20 that came through so that's really good news."
The HSD will be trialled throughout most Wheatbelt areas during harvest with demonstrations at Mullewa, Mingenew, Buntine, Wongan Hills, Wyalkatchem, Cunderdin, Corrigin, Kondinin, Lake Varley, Ravensthorpe, Esperance, Kojonup and Broomehill.
For time and location details contact AHRI.
