【正文】 8187:2020 (E) 11 Heat treatment Hoist chains of all types shall be hardened and/or case hardened from a temperature above the AC3 point and tempered before being subjected to the manufacturing proof force. Working load limits (WLL) The working load limits for the selected nominal sizes of hoist chains shall be as given in Table 5. NOTE The limits given in Table 5 have been calculated in accordance with annex A. For nominal sizes not included in Table 5 the working load limits shall be calculated in accordance with annex A. Additional stresses imposed on the hoist chain by the operation of power driven hoists shall be taken into account in selecting the nominal size for a particular application. In the case of hoist chain for power driven hoists, annex B shall be used for the calculation. Table 5 — Working load limits (WLL) Nominal size dn mm Chain type T t Chain type DAT t Chain type DT t 4 5 6 0,5 0,8 1,1 0,4 0,63 0,9 0,25 0,4 0,56 7 8 9 1,5 2 2,5 1,2 1,6 2 0,75 1 1,25 10 11 12 3,2 3,8 4,5 2,5 3, 3,6 1,6 1,9 2,2 13 14 16 5,3 6 8 4,2 5 6,3 2,6 3 4 18 20 22 10 12,5 15 8 10 12,5 5 6,3 7,5 mean stress N/mm2 2020) 160 100 1) Only for hand operated hoists. For power driven hoists: see annex B, Table . EN 8187:2020 (E) 12 Mechanical properties Manufacturing proof force (MPF) All hoist chains shall be subjected to the manufacturing proof force calculated on the basis given in annex A. For the selected nominal sizes values are given in Table 6. NOTE The formula and rounding rules for the calculation are also given in annex A. Table 6 — Manufacturing proof forces and breaking forces Nominal size dn mm Manufacturing proof force (MPF) kN min. Breaking force (BF) kN min. 4 12,6 20,1 5 19,6 31,4 6 28,3 45,2 7 38,5 61,6 8 50,3 80,4 9 63,6 102 10 78,5 126 11 95 152 12 113 181 13 133 212 14 154 246 16 201 322 18 254 407 20 314 503 22 380 608 Breaking force (BF) and total ultimate elongation (A) Samples of hoist chain in the finished condition shall have a breaking force at least equal to that calculated on the basis given in annex A and on pletion of the tensile test the minimum total ultimate elongation shall be in accordance with the values given in Table 7. EN 8187:2020 (E) 13 Bend deflection Single link samples of type T shall wi thstand the minimum deflection specified in Table 7 and shall be free from visible defects. Sample links of types DAT and DT shall withstand a force F0 equivalent to 2,5 times the working load limit of the hoist chain as given in without fracture. Surface cracks or visible defects shall not be considered to constitute fracture. Surface hardness The surface hardness at each of the three measuring points as shown in Figure 3 for all hoist chain types shall be at least equal to the value specified in Table 7. Table 7 — Total ultimate elongation, bend deflection and surface hardness hoist chain types T DAT DT Total ultimate elongation A1) % min 10 10 5 Deflection f mm min 0,8 dn 2) 2) Surface hardness 3) min dn 7 mm, HV 5 dn = 7 mm to 11 mm, HV 10 dn 11 mm, HV 10 360 360 360 500 500 450 550 550 500 1) As specified in of EN 8181:1996, except L , the original internal length of the test sample, is 0 used instead of Ln, the nominal internal length. 2) See . 3) For measuring points see . Case depth For fine tolerance hoist chain types DAT and DT, the case depth, when measured in accordance with the type test in , shall be within the limits related to nominal size dn given in Table 8. Table 8 — Case depth Nominal dn mm hoist chain types DAT DT 8 (0,04 177。 0,6 42 0,8 16,8 47,6 462 2,2 15,1 16 177。 0,4 30 0,6 12,0 34,0 330 1,6 10,8 11 177。 0,2 18 0,35 7,2 20,4 198 1,0 6,5 7 177。 however, should its use bee more generally accepted then the status of the information would need to be reviewed. 1 Scope This European Standard specifies the requirements related to safety for hoist chain, Grade T (type T quenched and tempered and types DAT and DT case hardened), for use in serial chain hoists manual and power driven. Type DAT and type DT hoist chains possess surface hardnesses greater than core hardness and are used for power driven chain hoists to offer greater resistance to wear. Type DT hoist chain differs from DAT hoist chain in having higher surface hardness and/or greater case depth to optimise wear resistance. The standard is applicable to electrically welded round steel short link hoist chains conforming to EN 8181. The range of nominal size of hoist chains covered by this European Standard is from 4 mm to 22 mm. The hazards covered by this European Standard are identified in clause 4. EN 8187:2020 (E) 5 2 Normative references This European Standard incorporates, by dated or undated reference provisions from other publications. These normative references are cited at the appropriate places in the text, and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or revision. For undated references, the latest edition of the publication referred to applies (including amendments). EN 2921:1991, Safety of machinery – Basic concepts – General principles for design – Part 1: Basic terminology, methodology. EN 2922:1991/A1:1995, Safety of machinery – Basic concepts – General principles for design – Part 2: Technical principles and specifications.