BS 1657:1950 - Specification for buttress threads
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BS 1657:1950

Specification for buttress threads

Status : Confirmed, Current   Published : August 1950



Included angle between pressure and trailing flanks of 52$0D; standard form of thread has a pressure flank angle of 7$0D; 'special' form has pressure flank normal to axis of screw. No rigid pitch/diameter relationship. Includes preferred series for diameters and pitches. Tables of tolerances and allowance for three classes of fit. System of gauging with notes on appropriate types and sizes of gauge. Method of measurement of effective diameter of buttress threads, tables of dimensions for the sizes of thread measuring cylinders.

Standard NumberBS 1657:1950
TitleSpecification for buttress threads
StatusConfirmed, Current
Publication Date17 August 1950
Confirm Date01 July 2017
Normative References(Required to achieve compliance to this standard)No other standards are normatively referenced
Informative References(Provided for Information)No other standards are informatively referenced
DescriptorsDimensions, Ring gauges, Thread pitch, Threads, Diameter, Linear measuring instruments, Dimensional tolerances, Asymmetrical threads, Calipers (instruments), Thread gauges, Nuts, Thread forms, Fits, Screws (bolts), Clearances, Diameter measurement
Title in FrenchFiletages de contreforts. Specification
Title in GermanTrapezgewinde. Spezifikation
ISBN0 580 35599 3
File Size592.1 KB

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