MACHINE PERFORMANCE NOTES
Most of Cap Coder’s machines are customised to suit specific applications and there are many factors to be considered in the overall performance of the equipment.
Some of the factors that require consideration are:-
Uniformity of product
- it is important to the performance of the machines that the product quality of bottles, caps, plugs etc. is maintained.
- Sometimes even a small change in the dimensions or material of a product can adversely affect performance; for instance in an automatic cap feed a cap size increase of 0.5 mm can stop the feed, or even a change of cap colour on a trigger spray can cause adverse lock-up due to an altered shrinkage rate.
Product spillage can only be evaluated by test
- The combination of fluid characteristics, container shape, temperature and acceleration/ deceleration present too many variants to consider other than by test.
- We are able to carry out spillage tests, for which we would require samples filled to the proper level with your fluid and we advise this to be done if there is any doubt.
Uniformity of torque
- If consistent tightening and untightening torques are to be achieved.
- The components must be of consistent quality.
- Cap tightening of manually placed caps require them to be pre-placed and pre-started
- If it is not possible to obtain consistent release torques for caps that have been manually tightened to a set torque value, a machine torque head will not rectify the problem and component quality should be carefully reviewed.
Health and Safety
- All machines are manufactured in accordance with our assessment of the requirements, and the current ISO standards.
- The assessment for a particular machine that you may wish to purchase is available for your consideration.
- If your Health and Safety requirement differs from ours an additional cost may be involved, so it is prudent to involve your Health and Safety Officer at an early date to establish what is needed.
Vibratory Bowl Feeder
- The inclusion of a vibratory bowl feeder is foremost a means of orienting caps/plugs in a uniform attitude that facilitates subsequent handling and they should not be considered in the context of a bulk supply hopper.
- Care should be taken not to overfill the bowls, as the caps may then bypass some of the orienting devices. Additionally, allowing the fill level to fall too low may reduce the feed rate of the bowl feeder.
- The bowl feeders are constructed to Health and Safety noise regulations, but when components are added and the working environment is included, the noise levels may rise above those limits. We therefore recommend acoustic hoods be used to reduce this risk.
THE IMPORTANCE OF COMPONENT QUALITY
Automatic handling of components such as plugs, caps and bottles will only be successful if a reasonable quality standard is maintained, and stoppages will occur if this is not done.
The types of problem that can occur are typically:-
|a)||Plugs with a moulding flash – small plastic plugs are very light and the pretence of a moulding flash can easily impair the transfer of the plug from one position to another.|
|b)||Caps that are a mismatch with the bottle giving quite often large variations in tightness – tolerances too wide, sometimes due to a cap colour change which alters the moulding shrinkage rate.|
|c)||Occasionally, after a cap has been tightened to a container and subsequently unscrewed, minute particles may become evident. This is known as ‘dusting’ and is a result of poor quality or a mismatch of products and/or thread profile The problem is sometimes caused because different materials are used in the manufacture of the cap and container and the abrasiveness of one against the other causes the contamination.
This can usually only be cured by consultation with the manufacturers and/or improvement in quality and specification.
|d)||Bottles (glass) – can vary dramatically in size and shape and it can be seen that variations between the alignment of the outside diameter of the body of the bottle and the base of the neck can give rise to periodic difficulties with pressing home of plugs.|
|e)||Bottles (plastic) – again the sizes can vary, but more importantly the product being filled; the fill level and the method of filling may have an effect on the shapes of the finished product. (temperature of the fill liquid, sidewall distotrtion of the bottle)|
These are just a few examples of quality problems that can cause a machine to malfunction or stop through sensing a fault condition.
Some conditions, such as a plug has not been inserted, or a cap feed track has run empty, can readily be sensed, but others, which could include a broken glass bottle, are not so easy, and it will be realised that the more the sophistication required to isolate the condition the higher the price.
It is therefore stressed that component quality is very important to smooth running and that if the quality is inadequate either steps should be taken to improve the component quality or the ensuing problems must be recognised as component problems and operating staff need to be of the right temperament and trained to deal with the stoppages that occur and the down time that ensues.