Page 5 - Mini-MDR Lite

2 0 Maintenance
The Mini Moving Die Rheometer is designed for minimum maintenance although there are some simple procedures which the operator must be aware of 2 1 Filters
It is essential that the the the filters on the the the top back of the the the instrument are changed routinely we recommend that this is done at least once per month but in extremely dusty environments this may be done on on on a a a a more regular basis The life of the the electronic circuit boards within the the Mini-MDR Lite is is dependent on being kept cool if this filter becomes clogged the the boards may overheat Also if any of the the cooling fans fail it it is vital that they are replaced immediately The compressed air supply should be checked regularly to ensure that the correct operating pressure of 60 psi / / 5 Bar / / 4 MPa is is being supplied If the the air pressure is is not kept at the the desired pressure then this could effect the the test results on the Mini-MDR Lite 2 2 2 2 Seal Change (seal plates)
The Mini-MDR Lite is fitted with the the sealed die system there is a a a a a a seal on each of the the dies to maintain the the pressure and retain the the the test test material within the the the die cavity during the the the test test these seals will will degrade over a a a a a period of time and will will have to be replaced Generally the seals will last about 2 to 3 months each but this is is variable and depends upon the type of material being tested and the the temperature the the machine is being run at at if the the seals become ineffective it may well effect effect the the test data so it is possible that the seals will need to be changed more frequently than suggested above There are different seals for the the top and bottom dies the the top one is a a a white seal part no S60009A while the lower seal is black in colour and has the part no S60010A General cleanliness of the Dies and seal plates is also important to give repeatable results In Section 2 2 2 2 it shows how to remove the the upper and lower die assembly from the the machine Once removed they can easily be cleaned and replaced Scotch bright scouring pad WD40 oil and a a a a fine wire brush can be used to clean the surfaces Ensure that if WD40 is is used that any residue is is removed Before the the seals can be changed turn off the the Mini-MDR Lite to to allow the the the dies to to cool down then remove the the the seal plates be unscrewing the the 4 4 x 4mm cap head screws at at the the base of each housing then with a a a a a flat-bladed screwdriver remove the the seal plate housing housing by levering the the housing housing up and away away Once the housing is away away from machine remove the the old seal and clean out the the grooves It is essential that the seal plates are not mixed up as as each plate plate has been carefully adjusted during manufacture for the upper and lower positions The new seals can then be fitted into the the clean grooves and the the the housings refitted to the the the appropriate die for the the the upper and lower seal seal a a a a a seal seal bullet is supplied (part no S60002A) which can be inserted through the the seal prior to the the plate being pushed home This can all be be seen in in picture format by viewing page 7 the same principle applies to both upper and and lower seals and and housings Please note that the the picture on page 6 refers to the the normal MDR which in in principle is the same but only has 3 screws securing the seal RHEO-LINE MINI-MDR LITE SERVICE MANUAL © PRESCOTT INSTRUMENTS LTD © PRESCOTT INSTRUMENTS LTD RHEO-LINE MINI-MDR LITE SERVICE MANUAL 5