Glossary and Abbreviations - Unido

Worked example 7: Fill weight adjustment
Check-weighings show bags of flour to be 5250g compared to a target weight of 5kg. Adjust the
coarse adjuster towards the front of the machine by one 250g division on the bar. Tests show that this
gives a fill weight of 4980g. Use the fine adjuster and give 4 turns towards the back of the machine.
The correct fill-weight of 5000g is now achieved and is set by locking the weights.
Maintenance
Ensure that counterbalanced weighing mechanisms are free to move up and down and the
pushrods are free to move. Bearings are sealed and do not require lubrication. If metal
bearings are fitted at the top of the pushrods, they should be lightly lubricated occasionally. It
is essential to keep the machine clean of flour dust, especially on support trays, weighbeams
and within the machine, otherwise inaccurate fill-weights may be produced. Regularly check
dust gaiters on the bag clamp rubbers and replace them before they are worn out.
Any inaccuracies in weighing are likely to be due to one of the following causes:
• Movement of pushrods is restricted
• Product feed is not directed at the centre of diverter chute
• Product build-up on diverter chute because feedrate is too high
• Incorrect position of adjusting weights
• Variations in product feedrate
Polythene bags are heat-sealed. Paper bags and all types of sacks can be sealed using an
electric sack stitcher (Fig. 5.18).
Remember: Do-it-yourself electrical wiring can kill you.
Get a professional electrician for all electrical work!
Blanchers
Hot water blanchers are made from aluminium pans. A mesh scoop is used to remove the hot
root crops. Steam blanchers use the same pans, and have a removable mesh base to hold the
roots above the boiling water. There is no maintenance required and pans should be cleaned
with detergent and rinsed with clean water after use.
Boiling pans
A stainless steel (or less desirably aluminium) pan placed directly over the heat source is
used to make sweet potato jam. There are two types of boiling pans: at smaller scales of
operation, a simple stainless steel (or less desirably aluminium) pan can be placed directly
over the heat source. However, viscous products such as jams are likely to burn onto this
type of pan unless great care is taken to control the heat and thoroughly stir the mixture as it
is being heated. This reduces the quality of the product and also significantly slows down
production because the pan must be cleaned between batches. At a larger scale, a ‘double
50