Product category:
Miscellaneous Instruments
News Release from: Mahr UK | Subject: Multisensor OMS400 measuring machine
Edited by the Manufacturingtalk Editorial
Team on 10 July 2003
Multisensor sees More Preform Bottles
Produced
Mold and Hotrunner Technology have for many years, been using a Mahr Multisensor OMS400 measuring machine, to ensure quality of their products.
At least once a day, many of us use a bottle of some sort, whether it be a soft drink container or a household cleaning agent of one type or another To the user, the effort is required to manufacture these plastic products is of no consideration
This article was originally published on Manufacturingtalk on 3 Jun 2003 at 8.00am (UK)
Related stories
New Entry Level 3D Multisensor From Mahr
The MarVision MS222 Optical CMM is complete with 3 sensors, camera, touch trigger probe and laser.
Multisensor CMM Improves Productivity at Goodrich
A major problem to the EDM cell's production team was the ability to obtain consistent results when doing a first article inspection.
We are only interested in the contents at the best possible price.
Mold and Hotrunner Technology, a leading manufacturer of precision moulds for the production of preforms, have for many years, been using a Mahr Multisensor OMS400 measuring machine, to ensure quality of their products.
However, the increasing cost pressure on one hand and quality improvements on the other, induced MHT to reduce the inspection costs while increasing the inspection sample size.
Further reading
The Most Accurate 3D Multisensor From Mahr
The MarVision Compact400, equipped with high precision air bearings, is said to be everything one would expect from a company which is renowned for its surface and form measuring instruments.
New Test Indicator From Mahr Impervious To Liquids
The new MarTest-Generation with its computer-optimised mechanism is a part of our consistent development and unrelenting commitment made over many decades, with our well-proven "Puppitast"-Series.
Fast and accurate NDT speeds production lines
The constant demand from customers for 'best quality', combined with the increasingly competitive nature of the marketplace, has accelerated the development of test methods.
Until now, and in addition to the Multisensor, different measuring instruments such as calipers, profile projector, special gauging fixtures and a balance were used to measure the required parameters.
The results had to be manually entered into the test record.
A lack of process control early on in the preform manufacture results in a number of quality problems during further processing.
The most frequent errors are uneven cavity filling, sink marks, joint-line swirls in the neck area, non-uniform weight distribution, crystalline and under filling in the neck area.
A bad form or pitch could cause the thread to break or the cap not to close.
The flange position, flank depth and width are all important for the automatic handling in bottling plants.
An outer contour error may effect the preform handling by the unloading robot when transferring to the moulding machine.
Wall thickness whether it be irregular or too thin can effect the blow-up behaviour.
Errors in roundness also cause problems with the blow-up behaviour as well as sealing and handling.
If the weight is too high then unnecessary expense is incurred.
For example, an excess weight of 0.5 g may cost several hundred thousand pounds per year.
If the weight is too low there may be a problem with the wall thickness.
The increasing demand for PET products and the necessity to increase the inspection quota called for a new solution.
The first machine was already running to full capacity.
For this reason, MHT contacted Mahr to develop a fully automatic measuring system to inspect the different preform types PCO, BPF, 1, 2, and 3 start threads, oil preforms, etc The solution was to use a robot loaded Mahr Multisensor measuring machine, equipped with a rotary table, a special universal fixture and a palette handling system.
In addition to the geometry inspection of the parameters, the weight of the individual preforms is automatically determined and fed into the measuring record.
Mahr's multisensor machine OMS400 using a touch trigger probe, camera and laser forms the basis for this solution.
Using a mouse, the operator selects the preform type and starts the process.
A pneumatic clamping fixture is located on the integrated rotary table and used to fix the preform.
A pneumatic gripper in the handling system takes the individual preforms from a pallet and positions them onto the clamping fixture.
When the measuring run is finished, the preform is removed and placed on a balance that determines its weight, which is then fed into the measuring record.
The preform is then replaced on the pallet.
The advantages of the automation and the application of multisensor technology are worthy of consideration and should be noted.
The combination of touch trigger probes with a camera and a laser allow for rapid and accurate measurement of all parameters.
The most suitable sensor is used for each measurement and so full potential is gained when choosing this machine within a automatic environment.
For example, the thickness of the bottom wall can only be measured using a camera, as there is no access for a touch trigger probe.
Other parameters however, could be measured by all sensors but process reliability can only be assured using touch trigger probe.
To start the program, the position and the start of the thread are determined using the camera and the rotary table.
The use of several manual measuring stations are no longer necessary.
Advantages for MHT? The measuring and handling time amounts to just over 5 hours as compared to 20 hours that were required with the manual measuring method used in the past.
Automatic measurement has resulted in faster and more reliable measuring results.
Resulting in a more controlled process which has reduced the scrap rate.
This has, in turn, has produced an increase in production which gives faster through put and quicker delivery times.
This increase in capacity has also meant that MHT are able to take on new work using the existing equipment.
• Mahr UK: contact details and other news
• Email this article to a colleague
• Register for the free Manufacturingtalk email newsletter
• Manufacturingtalk Home Page
Search the Pro-Talk network of sites
