The following image shows the first paragraph of Appendix 1 of AS2784. APPENDIX B RECOMMENDED PRACTICE...

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The following image shows the first paragraph of Appendix 1 of AS2784. APPENDIX B RECOMMENDED PRACTICE FOR TENSIONING BELT DRIVES DURING INSTALLATION AND CALCULATION OF THE RESULTANT FORCE IMPOSED ON THE SHAFT (Informative) BI GENERAL The high power ratings of wedge belts and V-belts necessitate the measurement of belt tensions with sufficient accuracy to prevent belt slip or overloaded bearings or to meet particularly arduous conditions. The following procedure is recommended for drives coming within the normal range for each belt section as defined in this Standard. B2 ORIGINAL TENSIONING OF BELT The length of the span should be measured in millimetres. At the centre of the span a force is to be applied with a spring scale in a direction perpendicular to the span, until the belt is deflected from the normal by an amount equal to- (a) (b) 0,01 mm for every millimetre of span length if the span length exceeds 500 mm (see Figure B1, Condition 2). For example, the deflection for a span of 1 m would be (1000x 0.01) mm, i.e. 10 mm. The force required for this deflection should be noted and compared with the value of P given in Table Bl. 0.02 mm for every millimetre of span length if the span length is 500 mm or less (see Figure BI, Condition 1); or In all cases, it is highly recommended that the pulley centres be fixed and that the larger pulley be then rotated at least four times before making the measurement. On a multiple belt drive, it is essential that a matched set of belts be used (see Clause 2.6) and the above procedure be carried out on each belt, the average value of these forces being compared with the specified values of P in Table I le Bl. With reference to Appendix B of AS2784 (you will need to download a full copy, see announcements for instructions) complete the following questions relating to the belt tension. The following image shows the first paragraph of Appendix 1 of AS2784. APPENDIX B RECOMMENDED PRACTICE FOR TENSIONING BELT DRIVES DURING INSTALLATION AND CALCULATION OF THE RESULTANT FORCE IMPOSED ON THE SHAFT (Informative) BI GENERAL The high power ratings of wedge belts and V-belts necessitate the measurement of belt tensions with sufficient accuracy to prevent belt slip or overloaded bearings or to meet particularly arduous conditions. The following procedure is recommended for drives coming within the normal range for each belt section as defined in this Standard. B2 ORIGINAL TENSIONING OF BELT The length of the span should be measured in millimetres. At the centre of the span a force is to be applied with a spring scale in a direction perpendicular to the span, until the belt is deflected from the normal by an amount equal to- (a) (b) 0,01 mm for every millimetre of span length if the span length exceeds 500 mm (see Figure B1, Condition 2). For example, the deflection for a span of 1 m would be (1000x 0.01) mm, i.e. 10 mm. The force required for this deflection should be noted and compared with the value of P given in Table Bl. 0.02 mm for every millimetre of span length if the span length is 500 mm or less (see Figure BI, Condition 1); or In all cases, it is highly recommended that the pulley centres be fixed and that the larger pulley be then rotated at least four times before making the measurement. On a multiple belt drive, it is essential that a matched set of belts be used (see Clause 2.6) and the above procedure be carried out on each belt, the average value of these forces being compared with the specified values of P in Table I le Bl. With reference to Appendix B of AS2784 (you will need to download a full copy, see announcements for instructions) complete the following questions relating to the belt tension.