BS 4060:1989 download free.Specification for Pressed wool felts.
1 Scope
BS 4060 specifies requirements for the following two types of pressed wool felt:
a) general purpose felts including packaging felts, and decorative felts:
b) precision felts.
Methods of test for chemical and physical properties are given in Appendix D and Appendix E respectively.
NOTE The titles of the publications referred to in BS 4060 are listed on the inside back cover.
2 Definitions
For the purposes of BS 4060 the following definitions apply:
2.1
felt
a fabric characterized by the entangled condition of most, or all, of the fibres of which it is composed
2.2
general purpose felts
felts used for packaging, clothing, decorative and similar purposes
2.3
precision felts
felts used in engineering applications, where close tolerances are necessary
2.4
pressed felt
a felt formed from a web or batt containing animal hair or wool, consolidated by the application of heat and mechanical action that causes the constituent fibres to mat together
2.5
white felt
felt which has the colour of natural unpigmented wool
NOTE White felts are used where the visual appearance is important
2.6
grey felt
felt, the colour of which has been obtained from using mixtures of coloured wools and other fibres
3 Materials
Felts shall be manufactured from wool, or mixtures of wool with natural or man-made fibres. The minimum wool content shall be as specified in Table I and Table 4.
NOTE 1 Felts complying with this standard may be white or grey, with a minimum wool content of 75 %, 90 % or 97 %, except for A9717D felt, which is dyed (see Table 1).
NOTE 2 The fibres should be blended, carded and felted to form a uniform product substantially free from permanent ridges and creases. The product should be free from all non-fibrous agents. e.g. stiffening, loading or reinforcing agents of any kind.
4 Designation
Felts shall be designated by a condensed technical description (see Table 1 and Table 4) containing the following:
a) a first letter to indicate whether the felt is general purpose (A) or precision (B);
b) a number, consisting of two digits, to indicate the minimum percentage wool content;
c) an oblique stroke;
d) a single digit number, 1 to 8, to indicate the hardness or density grade;
e) a letter to indicate the colour white (W), grey (G) or dyed (D);
NOTE If appropriate, interested parties may agree to include the additional designations in Table 6 and Table 7 to indicate that particular chemical andlor physical requirements have been
complied with (see 5.4 and 5.5):
Examples
A75/1W indicates the felt to be general purpose, with 75 % wool content, extra hard and white.
B97/1G6.1-6.6 indicates the felt to be a precision felt with 97 % wool content, extra hard, grey, having a minimum breaking strength of 5.5 MPa and having chemical properties conforming with 6.1 to 6.6 of Table 6.
5 Performance
5.1 General purpose felts
General purpose felts, including packaging felts, shall comply with Table 1 and Table 2.
NOTE Commonly manufactured thicknesses
are 1, 3, 5, 10. 15. 20 and 25 mm but other thicknesses may be specified by the customer.
5.2 Decorative felts
Decorative felts shall comply with 5.1 and shall, additionally, meet the minimum colour fastness ratings detailed in Table 3 (see also C.3.3).
5.3 Precision felts
Precision felts shall comply with Table 4 and Table 5.
5.4 Chemical properties
If felts are required to have particular chemical properties, the felts shall comply with the relevant requirements of Table 6.
NOTE 1 The purchaser should specify whether any particular chemical properties are required (see Appendix A). NOTE 2 For MoD purposes, general purpose felts and felts for aerospace purposes should comply with 5.1. 5.3 and Table 6.
5.5 Physical properties
If felts are required to have particular physical properties, such as breaking strength and oil retention, the felts shall comply with the relevant requirements of Table 7.
NOTE The purchaser should specify whether any particular physical properties are required (see Appendix A).
5.6 Special finishes
Felts shall be manufactured either with or without special finishes imparting. for example, rot, mildew, moth, flame or water resistance, or a combination of these properties.
NOTE 1 The purchaser should specify whether any special
finishes are required (see Appendix A).
NOTE 2 For aerospace purposes. felts should be rot-proofed
(see 3.7 of Table 6) in accordance with PCPL (normal process) of
BS 2087-1.
6 Inspection, sampling, conditioning
and testing atmosphere
6.1 Inspection
Each manufactured piece shall be visually inspected for defects, e.g. permanent ridges and/or creases and holes.
NOTE 1 Interested parties may agree to the nature and number of defects which may be permitted, on the marking of their positions in the roll or sheet and on the appropriate allowance to he made.
NOTE 2 Felts for MoD purposes should be substantially free from holes.
6.2 Sampling
6.2.1 Unless otherwise specified in the relevant test method, samples of the felt shall be taken from each lot of 200 m2 or less.
6.2.2 Samples shall be taken at least either 1 m from either end of a roll or 10 cm from either end of a sheet.
6.2.3 Each sample shall consist of a strip or strips cut from across the full width of the felt to give a total mass sufficient to perform all tests required and of adequate dimensions appropriate to the tests to be performed.
For chemical tests cut the sample into cubes having sides no more than 5 mm long. Condition the cubes for 24 h in accordance with 6.3. Mix the cubes together and randomly select a number of them to give a test specimen of mass appropriate to the test method under consideration.
6.3 Conditioning and testing atmosphere Unless otherwise specified in the relevant test method, conditioning and testing shall be carried out in the standard temperate atmosphere specified in BS 1051, i.e. a relative humidity of 65 ± 2 % and a temperature of 20 ± 2 °C.
Laboratory samples shall be conditioned by exposing them for at least 24 h in the conditioning atmosphere.
7 Marking
Pressed wool felts shall be marked with the following particulars:
a) the name, trade mark or other means of identification of the manufacturer;
b) the number and date of BS 4060, i.e. BS 4060:19891);
c) the felt type and designation in accordance with clause 4;
d) the nominal width, length and thickness of the piece or sheet.