BS ISO 7772-1:1998 download.Assessment of industrial laundry machinery by its effect on textiles Part 1 : Washing machines.
The rapid technical development of laundry machinery and the changes in the pattern of purchasing have led to an urgent need for a standard means of assessment of the effect of machine performance on textiles. Two different approaches to the provision of the necessary information were considered:
a) definition of essential specifications for laundry machinery, for use by agreement between manufacturer and customer (see for example ISO 939):
b) preparation of standard methods for rating and assessing the effect of the principal types of machine so that the test results obtained on machines of a similar type could be compared directly wherever the machines were located and whenever they were tested.
Iso 7772 deals with the second approach, since the urgent need was for procedures that could be used on a range of machines to evaluate their effect under reproducible conditions. including specification of the loads to be used.
Thus it will be possible to compare the basic effects of one machine against another, and a machine against a specification quoted in a contract. No performance level is set. Another advantage in the approach adopted is that the tests can be condu ted at any location where the necessary services are available.
It is hoped that, with the advance of techniques, and widespread use of ISO 7772. updated methods can he incorporated.
1 Scope
This part of ISO 7772 specifies methods for the assessment of the effect on textiles of washing machines. including batch-washing machines, continuous-washing machines and washer-extractors.
Methods are described for determining mechanical effects due to the rotary action of the machine, the rinsing effectiveness, the mixing time and the consumption of water, heat and power. Certain other effects such as retention of whiteness may be evaluated using the methods specified in ISO 4312.
In the case of batch.washing machines, this part of ISO 7772 applies only to machines with a capacity in excess of 7 kg.
The methods described in this part of ISO 7772 can he used separately1 and therefore any combination of them can be agreed on between the interested parties.
2 Normative references
The following standards contain provisions which, through reference in this text, constitute provisions of
bone..dry mass (11DM) (moisture content between 0,5 % and 1.0 %)
the mass of a textile article (or of a number of articles) after being dried in a specified manner, when successive determinations of mass after several drying procedures show no progressive change in mass of the textile greater than 0,5 %
NOTE Specif’wd drying procedures include repeated proceaaing of the article or articles in a heated tumbler from which the exhaust air reaches a tomperature of not less than SO ‘C nor more than 120 ‘C, or repeatedly passing the article or articles through a flatwork ironing machIne. These temperatures are appropriate to cotton fabrics which constitute the Lost loads and teat pieces specified in this pail of ISO 7772.
3.5
cage
that part of a washing machine which rotates and contains the load during the washing and rinsing processes
3.6
carrier
cotton fabric, complying with ISO 2267, cut into squares measuring 1 000 mm x 1 000 mm in which “windows” are cut for attachment of MA test pieces (see 3.18). to ensure proper movement during washing and for ease of identification after processing
3.7
compartment
a subdivision of a cage
3.8
continuous-washing machine
a washing machine in which textile articles pass continuously or intermittently from the loading point.
through the machine, to the discharge point
3.9
dwell time
the time for which the cage is stationary during reversals in the direction of rotation
3.10
extraction
the mechanical removal of liquor from wet textiles
3.11
final extraction
in a washer-extractor, the final stage of a process during which the cage rotates at its highest speed in order
4.3.3 If the installation and/or running conditions are outside the limits stated by the manufacturer, t.hey shall be agreed to by him or his authorized representative. Failing such guidance or agreement, the installation and/or test conditions shall be acceptable to the party commissioning testing. Where appropriate spaces are not provided in the test report forms, particulars of any differences between the manufacturer’s stated limits and the actual conditions as measured or observed during testing shall be clearly set out as an annex and attached to the test report.
4.3.4 The power rating of the electric motor or motors, the function which each motor performs and the manufacturer’s stated peak loading and running load in kilovolt amps shall be recorded in a table with the format as given in Table 5.
NOTE Sec clause 7 for the measurements of the actual conditions of supply of services to the test machine during the tests and for the provision for the recording of such mt!asun,mc’nts in comparison with the figures recommended by the manufacturer.
4.3.5 The manufacturer’s stated or recommended requirements in respect of electric-power supply, water, steam or heat-transfer fluid and any other external services (e.g. compressed air) shall be obtained and recorded as given in Table 6.
NOTE See clause 7 for the measurements of the actual conditions of supply of services to the test machine during the tests and for the provision for the recording of such measurements in comparison with the figures recommended by the manufacturer.
4.4 Tolerances
Tolerances are given for numerical values of dimensions, temperatures and times that are considered critical. If no tolerance is given, the precision of the measurements need be only that to be expected when using common instruments and reasonable care. The precision is further indicated by the number of significant figures in the values given.
5 Relationship between liquor quantity and dip level for open-drum washing machines
5.1 Principle
The quantity of liquor required to produce specified running-dip levels at different loading factors is determined by adding water through a meter and observing the water level through a sight glass.
5.2 Apparatus and materials
5.2.1 Indicating sight glass, fitted to the washing machine (see Figure 1).
5.2,2 Water meter.
5.2.3 Cotton test sheets, which have been laundered previously, in sufficient number to load the machine to
the recommended loading factors of 0.100 kg/I. 0.083 kg/I and 0.067 kg/I to within an accuracy oft 5%.