Potato Review

54 POTATO REVIEW JULY/AUGUST 2022 MACHINERY New destoner web undergoes tough durability tests A NEWdestoner web has undergone some tough durability tests, with manufacturer Gri working alongside the University of Birmingham to test structure and strength of web rods to maximise durability and robustness, before now beta testing them in the eld. e aim of the project was to see how web rod heavy duty centres (HDCs) could be improved for modern growers, following an upgrade to the manufacturing equipment that creates them. Dr Richard Turner, research fellow, University of Birmingham, said: “We tested the new heat treatment used by Gri , along with the additional 80% of steel used in the HDC, to determine strength and ductility in comparison with its old heat treatment method,” explains Dr Richard Turner, research fellow, University of Birmingham. “ rough various tests, we discovered the strength, exibility and internal properties of the new webs, nding the new heat-treated steel exhibited much higher strength than previous models. “With this type of material, it’s often a trade-o between toughness and strength. If a material is too strong, it can be brittle, so it’s important to promote toughness – strength and exibility – as well as strength. “Our analysis into the internal fractography of the new rod revealed the arrangement of the fractured cross-sections were a microstructure that promotes both excellent strength and the required exibility to maintain structural integrity for a considerable amount of time. “Essentially, the research found the tested web rods are now able achieve the optimum mechanical properties of strength and durability for a HDC during use.” Destoner webs experience the toughest conditions of machines in the eld, so it’s important to test their durability before customer use, Gri ’s Commercial Manager David Wood said. e Black Country-based manufacturer has two centuries of chain- making heritage, so its team understands the importance of strength in harsh conditions. “During the destoning process, the web sees extreme conditions that can potentially reduce the lifespan of the web. e amount of material on the machine, combined with long working hours during destoning season, can be detrimental to the integrity of the web,” said David. “We’re also seeing tighter and tighter timescales for modern farmers, meaning it’s becoming even more important to minimise downtime where we can. We’ve tested our newest rods in a lab to understand how we can make them as durable as possible, and now it’s time for beta testing in the eld.” David said the team had recognised a need to advance current destoner webs by improving the rods used. “Some of our end-users are working with webs that are destoning for 14 hours per day, with stones weighing over 50kg. is means there can be two tonnes of material on a web at any given time, so it was important to focus on improving the toughness of the material to reduce downtime,” he said. “ e centre of the web is where it experiences the most force, and this is often also the least supported part of the web, so it can be easy for this section to give way and cause signi cant downtime. To combat this issue, we developed a new web rod with a heavy duty centre.” He said the eld testing now taking place will enable the team to understand the exact lifespan of the rods and web. MOBILE SORTER LAUNCHED GRIMME UK and Haith Group have revealed their latest major joint project - a mobile optical sorter. Designed to automate the removal of stone, clod and foreign debris from potatoes and help growers cope with labour shortages, demonstrations of the new PRO Sort are now being organised. At the heart of the PRO Sort is a TOMRA 3A optical sorter which is capable of handling up to 100 tonnes per hour with high levels of accuracy. As the PRO Sort is a modular unit, it can be used either in the eld or on a farm and be easily integrated into a new or existing grading line. The TOMRA 3A employs Near Infra-Red multi-spectral sensors for an unobstructed assessment of every object ‘in flight’, identifying between potatoes and foreign material. As well as debris, the 3A’s colour sensors can detect green potatoes, which like the debris, are removed at the end of the conveyor belt by finger ejectors. Haith’s Managing Director Duane Hill said the sorter had been developed in response to an increasing number of growers who are finding it difficult to find people to sort and pick their crop before it goes into store or is delivered to processors. He said: “Having integrated the TOMRA 3A into many of our grading projects, it was logical to put it at the heart of this unit.” By working in partnership on the development of the PRO Sort, Haith and GRIMME have ensured that the new unit can be used in conjunction with the GRIMME RH receiving hopper to transfer potatoes into store and the GRIMME Cleanloader. GRIMME UK Ltd’s Managing Director, Patrick Graf Grote, said the mobile sorter would save growers time and money and allow them to operate e ciently despite the widely-reported labour shortage. “ e PRO Sort can be used as a standalone machine, combined with our receiving hopper and CleanLoader, or added easily to a Haith line. Having spoken to several customers about the PRO product line, we are con dent it will be very well received and the demonstration days later in the year will be very popular.”