BS 8498-2008 pdf free download

BS 8498-2008 pdf free download.British Standards for screw threads and screw gauges Introduction and guidance.
This BS 8498 gives a general introduction to the series of British Standards specifying single start parallel screw threads of Whitworth, British Association (BA.). Unified and ISO metric forms, the series of British Standards specifying the corresponding screw gauges with which they are to be used, and the British Standard specifying the gauge blanks.
2 General
The screw thread standards and the corresponding screw gauge standards are listed in Table 1.
NOTE For details of the British Standard for gauge blanks (85 1044.1:2008), see Clause 6.
3.1 Screw threads
3.1.1 Whitworth threads (BS 84:2007)
85 84:2007 specifies external and internal threads in the following thread series:
a) a coarse thread series, the British Standard Whitworth (B.S.W.) series, with nominal diameters in the range ‘h in to 6 in.
b) a fine thread series, the British Standard fine (B.S.F.) series, with nominal diameters in the range i1 in to 4¼ in.
NOTE The tables of limits and tolerances for the B.S.F series extend up to the 3 in size only, since nominal sizes above 3 in are rarely used.
c) a supplementary selected thread (WHIT. S.) series with nominal diameters from /4 in to 7 in.
d) a truncated Whitworth form series.
BS 84:2007 specifies limits of sizes, and tolerances, for three tolerance classes of external threads, close, medium and free, and two classes of internal threads, medium and normal. BS 84:2007 specifies requirements for unpiated threads and also for metal plated threads (including threads plated with cadmium, nickel, tin or zinc) with a thickness of plating of the order of 0.000 2 in. A summary of the data tabulated in BS 84:2007 is given in Table 2.
NOTE The tables of limits and tolerances for the B.S.F series extend up to the 3 in size only, since nominal sizes above 3 in are rarely used.
c) a supplementary selected thread (WHIT. S.) series with nominal diameters from ¼ in to 7 in.
d) a truncated Whitworth form series.
BS 84:2007 specifies limits of sizes, and tolerances, for three tolerance classes of external threads, close, medium and free, and two classes of internal threads, medium and normal. BS 84:2007 specifies requirements for unplated threads and also for metal plated threads (including threads plated with cadmium, nickel, tin or zinc) with a thickness of plating of the order of 0.000 2 in. A summary of the data tabulated in BS 84:2007 is given in Table 2.BS 8498-2008 pdf free download.