This Part of JB/T 8521 specifies the methods of rating and testing the roundslings (hereinafter referred to as slings) up to 100t maximum working limit load in straight lift and two-, three-, and four-leg slings(with or without fittings), made of such man-made fibres as polyamide, polyester and polypropylene.
This Part applies to general lifting services of materials and goods.
Lifting operations not covered by this Part include the lifting of persons, potentially dangerous materials such as molten metal, acids, glass sheets, fragile article, nuclear reactors and where special conditions apply.
Slings conforming to this Part are suitable for use and storage in the following temperature ranges:
a) Polyester and polyamide: -40℃~100℃;
b) Polypropylene: -40℃~80℃.
This Part does not apply to the types of sling indicated below:
a) Slings designed for securing or lashing of cargoes to each other on pallets and platforms or in vehicles;
b) Slings of tubular webbing without filling.
This Part deals with the technical requirements to minimize the hazards listed in Clause 4 which can arise during the use of slings when carried out in accordance with the instructions and specifications given by the manufacturer or authorized representative.
2 Normative References
The provisions of the following normative references become that of this Part after being quoted by this Part of JB/T 8521.For dated reference, subsequent amendments (excluding amending errors) to, or revisions of, any of these publications do not apply. However, all parties coming to an agreement according to this Part are encouraged to study whether the latest editions of these references are applicable. For undated references, the latest editions apply.
GB 251-1995 Gray Scale for Assessing Staining(idt ISO 105/A 03: 1993)
GB/T 16825.1 Verification of Static Uniaxial Testing Machines - Part 1: Tension/compression Testing Machines - Verification and Calibration of the Force-measuring System (GB/T, 16825.1 - 2002, ISO 7500-1.1999, DT)
GB/T 16856 Safety of Machinery - Principles for Risk Assessment (eqv pr EN1050: 1994)
GB/T 19001 Quality Management Systems - Requirements (idt ISO 9001: 2000)
3 Terminologies and Definitions
For the purposes of this Part, the following terminologies and definitions apply.
3.1
Round sling
Endless flexible sling consisting of a loadbearing core of yarn, completely enclosed in a woven cover, with or without fitting (see Figure 1).
3.2
Multi-leg sling assembly
Sling assembly, consisting of two, three or four identical slings attached to a master link (See table 2).
3.3
Representative sample
Sling representative of slings of the same type, which is used for verification purposes (See 6.2 and 6.3)
Note: This may differ from the production sling in length only.
JB/T 8521.2-2007 The following standards are cited：
