ISO 1268-11:2005 pdf download.Fibre-reinforced plastics - Methods of producing test plates — Part 11: lnjection moulding of BMC and otherlong-fibre moulding compounds-Small plates.
5.2.3 A convenient way of determining the hold pressure PH. a parameter which is frequently not specified, is by the following procedure:
Starling from zero, gradually increase the pressure on the material until the mould.ngs are free from sink marks, voids and other visible faults and have minimum flash. Use this pressure as the hold pressure.
This procedure can be used for most Injection-moulding presses.
5.2.4 Ensure that the hold pressure is maintained constant until the material Ni the gate region has cured, i.e. until the mass of the moulding has reached an upper limiting value under these conditions.
5.2.5 Discard the mouldings until the machine has reached steady-state operation. Then record the operating conditions and begin test specimen collection.
During the moulding process, maintain the steady-state conditions by suitable means. e.g. by checking the mass of the moulding 01M
5.2.6 In the event of any change in material, empty the machine and clean it thoroughly. Discard at least 10 mouldings made using the new material before beginning test specimen collection again.
5.3 Measurement of mould temperature
Determine the mould temperature T after the system has attained thermal equilibrium and immediately after opening the mould Measure the temperature of the mould-cavity surface at several points on each side of the mould cavity using a surface thermometer. Between cacti pair of readings, cycle the mould for a minimum of 10 cycles before continuing with the next measurement. Record each measurement and calculate the mould temperature as the average of all the measurements.
Starling from zero, gradually increase the pressure on the material until the mould.ngs are free from sink marks, voids and other visible faults and have minimum flash. Use this pressure as the hold pressure.
This procedure can be used for most Injection-moulding presses.
5.2.4 Ensure that the hold pressure is maintained constant until the material Ni the gate region has cured, i.e. until the mass of the moulding has reached an upper limiting value under these conditions.
5.2.5 Discard the mouldings until the machine has reached steady-state operation. Then record the operating conditions and begin test specimen collection.
During the moulding process, maintain the steady-state conditions by suitable means. e.g. by checking the mass of the moulding 01M
5.2.6 In the event of any change in material, empty the machine and clean it thoroughly. Discard at least 10 mouldings made using the new material before beginning test specimen collection again.
5.3 Measurement of mould temperature
Determine the mould temperature T after the system has attained thermal equilibrium and immediately after opening the mould Measure the temperature of the mould-cavity surface at several points on each side of the mould cavity using a surface thermometer. Between cacti pair of readings, cycle the mould for a minimum of 10 cycles before continuing with the next measurement. Record each measurement and calculate the mould temperature as the average of all the measurements.
