BS 5053:1985 download. Methods of test for Cordage and webbing slings and for fibre cores for wire ropes.
1 Scope
BS 5053 describes methods of testing and the rate of sampling for cordage (see clause 2) made from either natural or man-made fibres, webbing slings made from man-made fibres and natural or man-made fibre cores for wire ropes.
NOTE 1 The testing of twines and cords for and in fishing nets is not covered in this standard. The testing of these materials is described in BS 4650 and BS 4674.
NOTE 2 The titles of the publications referred to in this standard are listed on the inside back cover.
2 Definitions
For the purposes of BS 5053 the definitions given in BS 3724 apply together with the following.
2.1
cordage
a load bearing article made by assembling fibres or filaments with twisting or plaiting, including twines, cords, lines and ropes
NOTE Fibre cores for wire ropes while not load bearing articles are included within this definition.
2.2
batch
the definite quantity of a commodity manufactured or produced under conditions that are presumed uniform, consisting of articles of the same type and dimensions
2.3
package
the unit of packaging in which the goods are supplied
2.4
webbing sling
a sling consisting of a narrow woven fabric generally of coarse weave and multiple plies, sometimes terminated in end fittings, the prime function of which is load bearing
2.5
representative sling
one of a production batch of slings having the same webbing type, material, strength and width, the same stitch pattern and the same end fittings (if any), but not necessarily the same length
3 Sampling
3.1 General
Determine the number of samples required in accordance with 3.2 to 3.6 and take the samples from the batch at random.
11 Procedure
11.1 General
Insert the specimen in the testing machine (8.1 or 8.2), increase the load continuously until the specimen breaks and record the maximum load attained. Should any specimen slip in the grips (movement around the bollards during tightening with bollard grips being ignored) disregard the result and take a further specimen for testing.
11.2 Location of rope fracture for cordage of 10 mm diameter and above
As damage caused by the holding devices can seriously reduce the results obtained, before applying the load, place limiting marks “r” on the specimen as follows:
a) for wedge grips (see Figure 3), in line with the grips:
b) for bollard grips (see Figure 4), 150 mm from the last turn of the splice;
c) for cor.de-chasse grips (see Figure 5). where the rope leaves the cor-de-chasse.
On completion of the test, determine the location of the fracture of the test length in order to establish whether or not the test result is truly representative of the rope strength.
Breaking should occur between the marks at both ends of the specimen. If breaking occurs outside these marks and the load recorded is at least 90 % of the specified breaking load, then regard the result as representative of the rope strength. Otherwise disregard the result and conduct a further test.
NOTE For test results to which the 90 % of the specified breaking load applies, it should not be assumed that the breaking load of either undamaged or unspliced rope would be represented by the application of the factor 10/9.
Enter the actual breaking load and the position of the break, e.g. “clear of the grips” or “adjacent to the grips” on any certificates. Enter also any contributory factors.
11.3 Calculation of breaking load of ropes from yarn breaking load tests
11.3.1 General. Where suitable gripping or holding facilities are not available, calculate the approximate breaking load of natural fibre ropes of 48 mm diameter and over and of man-made fibre ropes of 26 mm diameter and over from the average strength of the yarns.
NOTE 1 This should be agreed between the purchaser and the supplier.
NOTE 2 This method is not applicable to ropes having parallel cores, nor to ropes constructed from layers of different materials. Only an actual rope test is acceptable in these cases.
14 Determination of co-ordinates up to breaking point
Insert a specimen in accordance with 9.1.1 or 9.1.2 in the test machine and apply tension to the specimen in accordance with 5.1. Select a suitable gauge length L in accordance with 9.2. Increase the load continuously and record the force/elongation co-ordinates at intervals until the specimen breaks.
15 Determination of co-ordinates after simulated use
Insert a specimen in accordance with 9.1.1 or 9.1.2 in the test machine and apply tension to the specimen up to 50% of the specified minimum breaking load. Relax the tension and re-apply it for a total of 10 cycles, the times in the tensioned and relaxed states being as short as possible. Allow a period of I h in the relaxed state after the 10th cycle and then apply tension to the specimen in accordance with 5.1. Select a suitable gauge length L,, in accordance with 9.2. Increase the load continuously and record the force/elongation co-ordinates at intervals until a tension equal to 75 % of the specified breaking load is reached. At no point during the test shall the specimen be disturbed or removed from the test machine.
21 Resistance to solar degradation in
polypropylene cordage
21.1 Principle
A specimen of rope is weathered at an outdoor station for a given period concurrently with control specimens of a given formulation. The percentage retained strengths of both test and control specimens are compared.
21.2 Apparatus
2 1.2.1 Exposure frame. A wooden or aluminium alloy framework inclined at 45° to the horizon and aligned in a south-facing direction in the northern hemisphere or north-facing in the southern hemisphere. The area beneath and in the vicinity of the weathering racks shall be characterized by low reflectance. The racks shall be located so that no shadow from a neighbouring obstruction having an angle of elevation greater than 200 shall fall on them. There shall be a space of at least 750 mm between the base of the rack and the ground or other surface on which it stands.
21.2.2 Breaking load apparatus, as described in clause 8.
21.3 Specimens
2 1.3.1 General. Five specimens. both of the control rope and the test rope, shall he used for measurement of initial breaking load, and five specimens each also for exposure. Each specimen shall be of sufficient length to allow the measurement of breaking load in accordance with section 3.
The specimens shall be of nominally 12 mm diameter 3-strand plain or hawser laid construction and shall comply in all other respects with BS 4928.
21.3.2 Test specimens. Test specimens shall he of a construction as similar to that of the control specimens as possible.
2 1.3.3 (ontrol specimens. Control specimens shall be produced from fibrillated film yarn, and made from a polypropylene homo-polymer of melt index 3 to 3.5 containing 0.1 % of a phenolic antioxidant, 0.25 % of a thioester synergist identified and determined in accordance with BS 2782:Methods 434A and 434D and 1 % of iron(III) oxide by mass determined in accordance with clauses 19 and 20.
The iron(lll) oxide used shall be a synthetically produced iron(III) oxide consisting of at least 97 % iron(III) oxide, less than 3 % total oxide impurities such as alumina, silica or water, and shall be unaffected by calcination.