Miller Magazine Issue: 154 October 2022

64 COVER STORY MILLER / OCTOBER 2022 roll scrapers are essential to the correct operation of the rolls. Too often one will find rolls ringing because the scrapers are worn out, or not properly adjusted to be “just touching” the roll surface. When carrying out plan sifter maintenance, a miller must make sure that the sieves used are at the correct tension and that the sieve cleaning elements are functioning properly. When re- placing torn or burst covers, the correct aperture covers are used and the sieves repacked in their exact location within the cabinet ( miller’s often get the cleaning team to carry out this function, which is carried out incorrectly). This results in the mill stopping almost immediately after restarting, due to incorrect sieves or sieve boxes being miss-placed in the cabinet. Incorrect feed distribution to the rolls results in the feed rolls stopping and starting. The effect of this is, the plansifters have erratic flow resulting in bare dressing and high ash flour pro- duced. It is therefore pertinent that the feed to all the rolls in the mill to be constantly fed with full even flow of stock across the entire length of the grinding rolls. MIXING AND BLENDING Ensuring that the correct quantity of any additives, enzymes and other necessary ingredients for mixing and blending is drawn by the miller in charge and the quantity remaining after completion of the specific batch, is reconciled with the quantity of product scheduled for mixing. Detachers, Impact, pin mills and drum detachers, are in- stalled immediately after reduction rolls to break up any flakes generated by the action of the rolls, allowing for the ease of separation in the following sifters. Regular recom- mended inspection and adjustment or repair is necessary as the rotating pins and the beaters of the drum detachers do become work. Regular lubrication of bearings of the drum detachers is necessary too. The introduction of sterilator into the final flour stream helps prevent or reduce infestation of the final product and has to be inspected daily for potential leaks from the seals of the rotating shaft. FLOUR STREAM INSPECTION AND ANALYSIS The question here is - how often do millers carry out ash curve analysis in their mills. Millers often don’t even look at flour streams regularly, they only inspect this when there is a com- plaint from QA. Inspecting at least twice per shift is preferable to ensure constant flour quality. Scales are an important aspect of the entire milling process. All weighers should be checked for accuracy at least once a month during planned maintenance shutdowns. During this time, the miller must also check the condition of the fluted and smooth rolls and plan for the necessary roll replacements. Poorly surfaced rolls contribute to loss of extraction and out of spec production. Mandatory Photo Credit © Kevin Chamberlain