WHITWORTH THREAD

Descriptions

Whitworth threads were the world's first national screw thread standard, devised by Sir Joseph Whitworth in 1841. They are an imperial (inch-based) system characterized by a distinct 55° thread angle and rounded roots and crests.

Key Characteristics

Thread Angle: All Whitworth threads, including BSW and BSF, have a symmetrical V-profile with a 55° included angle between the thread flanks. This is a key difference from the 60° angle used in modern metric and Unified threads.
Thread Profile: The threads feature unique rounded roots and crests, designed to distribute stress effectively and provide excellent fatigue resistance.
Designation: Dimensions are specified in imperial units, using inches and "Threads Per Inch" (TPI) rather than metric pitch measurements.
Standardization: The standard is codified in British Standard BS 84.

BSW vs. BSF Threads

The Whitworth system encompasses two main series for general engineering:

BSW (British Standard Whitworth): This is the original, coarse-pitch thread series, primarily designed for general engineering applications like holding cast iron components or locomotives together. Its coarse pitch provides superior strength in softer materials and resistance to stripping.
BSF (British Standard Fine): This series was developed later as a fine-pitch alternative to BSW. BSF threads have the same 55° profile as BSW but a finer pitch, which provides increased core strength and better resistance to loosening from vibration, making it common in automotive and aviation applications before metric standardisation.

Specifications

No detailed specifications are available for this product.

Downloads

There are no downloads for this product.

Code	Description	Price	Quantity
SKSTW012012	1/8 WH X 1/8 SOCKET SETSCREW 580 In Stock for despatch	Price Unavailable	- +
SKSTW012025	1/8 WH X 1/4 SOCKET SETSCREW Out of Stock	£29.50 (exc VAT) per HUND £35.40 (inc VAT)	- +
SKSTW012050	1/8 WH X 1/2 SOCKET SETSCREW 148 In Stock for despatch	Price Unavailable	- +
SKSTW019019	3/16 WH X 3/16 SOCKET SETSCREW 155 In Stock for despatch	Price Unavailable	- +
SKSTW019025	3/16 WH X 1/4 SOCKET SETSCREW 229 In Stock for despatch	Price Unavailable	- +
SKSTW019031	3/16 WH X 5/16 SOCKET SETSCREW 94 In Stock for despatch	Price Unavailable	- +
SKSTW019037	3/16 WH X 3/8 SOCKET SETSCREW 250 In Stock for despatch	Price Unavailable	- +
SKSTW019050	3/16 WH X 1/2 SOCKET SETSCREW 35 In Stock for despatch	Price Unavailable	- +
SKSTW019062	3/16 WH X 5/8 SOCKET SETSCREW 78 In Stock for despatch	Price Unavailable	- +
SKSTW019075	3/16 WH X 3/4 SOCKET SETSCREW 11 In Stock for despatch	£77.20 (exc VAT) per HUND £92.64 (inc VAT)	- +
SKSTW019100	3/16 WH X 1" SOCKET SETSCREW 214 In Stock for despatch	Price Unavailable	- +
SKSTW025025	1/4 WH X 1/4 SOCKET SETSCREW 143 In Stock for despatch	£23.77 (exc VAT) per HUND £28.52 (inc VAT)	- +
SKSTW025025CP	1/4 WH X 1/4 SOCKET SETSCREW CONE POINT Out of Stock	£124.00 (exc VAT) per HUND £148.80 (inc VAT)	- +
SKSTW025025P	1/4 WH X 1/4 SOCKET SETSCREW Out of Stock	£61.90 (exc VAT) per HUND £74.28 (inc VAT)	- +
SKSTW025031	1/4 WH X 5/16 SOCKET SETSCREW 170 In Stock for despatch	Price Unavailable	- +
SKSTW025037	1/4 WH X 3/8 SOCKET SETSCREW 58 In Stock for despatch	Price Unavailable	- +
SKSTW025037P	1/4 WH X 3/8 SOCKET SETSCREW ZINC PLATED Out of Stock	£67.80 (exc VAT) per HUND £81.36 (inc VAT)	- +
SKSTW025050	1/4 WH X 1/2 SOCKET SETSCREW 172 In Stock for despatch	£27.40 (exc VAT) per HUND £32.88 (inc VAT)	- +
SKSTW025050CP	1/4 WH X 1/2 SOCKET SETSCREW CONE POINT Out of Stock	£115.90 (exc VAT) per HUND £139.08 (inc VAT)	- +
SKSTW025062	1/4 WH X 5/8 SOCKET SETSCREW 240 In Stock for despatch	Price Unavailable	- +
SKSTW025075	1/4 WH X 3/4 SOCKET SETSCREW 243 In Stock for despatch	£19.46 (exc VAT) per HUND £23.35 (inc VAT)	- +
SKSTW025075P	1/4 WH X 3/4 SOCKET SETSCREW ZINC PLATED Out of Stock	£111.90 (exc VAT) per HUND £134.28 (inc VAT)	- +
SKSTW025100	1/4 WH X 1" SOCKET SETSCREW 100 In Stock for despatch	£33.20 (exc VAT) per HUND £39.84 (inc VAT)	- +
SKSTW025150	1/4 WH X 1.1/2 SOCKET SETSCREW 9 In Stock for despatch	Price Unavailable	- +
SKSTW025200	1/4 WH X 2" SOCKET SETSCREW Out of Stock	£525.40 (exc VAT) per HUND £630.48 (inc VAT)	- +
SKSTW031025	5/16 WH X 1/4 SOCKET SETSCREW 110 In Stock for despatch	Price Unavailable	- +
SKSTW031031	5/16 WH X 5/16 SOCKET SETSCREW 8 In Stock for despatch	Price Unavailable	- +
SKSTW031037	5/16 WH X 3/8 SOCKET SETSCREW 20 In Stock for despatch	£21.10 (exc VAT) per HUND £25.32 (inc VAT)	- +
SKSTW031037CP	5/16 WH X 3/8 SOCKET SETSCREW CONE POINT Out of Stock	£113.50 (exc VAT) per HUND £136.20 (inc VAT)	- +
SKSTW031050	5/16 WH X 1/2 SOCKET SETSCREW 166 In Stock for despatch	£193.10 (exc VAT) per HUND £231.72 (inc VAT)	- +
SKSTW031050P	5/16 WH X 1/2 SOCKET SETSCREW ZINC PLATED Out of Stock	£79.60 (exc VAT) per HUND £95.52 (inc VAT)	- +
SKSTW031062	5/16 WH X 5/8 SOCKET SETSCREW 55 In Stock for despatch	£45.00 (exc VAT) per HUND £54.00 (inc VAT)	- +
SKSTW031075	5/16 WH X 3/4 SOCKET SETSCREW 119 In Stock for despatch	£88.12 (exc VAT) per HUND £105.74 (inc VAT)	- +
SKSTW031100	5/16 WH X 1" SOCKET SETSCREW 27 In Stock for despatch	Price Unavailable	- +
SKSTW031125	5/16 WH X 1.1/4 SOCKET SETSCREW Out of Stock	Price Unavailable	- +
SKSTW031150	5/16 WH X 1.1/2 SOCKET SETSCREW 285 In Stock for despatch	Price Unavailable	- +
SKSTW031175	5/16 WH X 1.3/4 SOCKET SETSCREW Out of Stock	£262.80 (exc VAT) per HUND £315.36 (inc VAT)	- +
SKSTW031200	5/16 WH X 2" SOCKET SETSCREW 10 In Stock for despatch	Price Unavailable	- +
SKSTW037037	3/8 WH X 3/8 SOCKET SETSCREW 436 In Stock for despatch	Price Unavailable	- +
SKSTW037050	3/8 WH X 1/2 SOCKET SETSCREW 176 In Stock for despatch	£286.05 (exc VAT) per HUND £343.26 (inc VAT)	- +
SKSTW037050P	3/8 WH X 1/2 SOCKET SETSCREW ZINC PLATED Out of Stock	£32.10 (exc VAT) per HUND £38.52 (inc VAT)	- +
SKSTW037062	3/8 WH X 5/8 SOCKET SETSCREW Out of Stock	£119.50 (exc VAT) per HUND £143.40 (inc VAT)	- +
SKSTW037075	3/8 WH X 3/4 SOCKET SETSCREW 87 In Stock for despatch	Price Unavailable	- +
SKSTW037087	3/8 WH X 7/8 SOCKET SETSCREW 50 In Stock for despatch	Price Unavailable	- +
SKSTW037100	3/8 WH X 1" SOCKET SETSCREW 81 In Stock for despatch	Price Unavailable	- +
SKSTW037100P	3/8 WH X 1" SOCKET SETSCREW ZINC PLATED Out of Stock	£171.40 (exc VAT) per HUND £205.68 (inc VAT)	- +
SKSTW037125	3/8 WH X 1.1/4 SOCKET SETSCREW Out of Stock	Price Unavailable	- +
SKSTW037150	3/8 WH X 1.1/2 SOCKET SETSCREW 2 In Stock for despatch	Price Unavailable	- +
SKSTW037175	3/8 WH X 1.3/4 SOCKET SETSCREW 33 In Stock for despatch	Price Unavailable	- +
SKSTW037200	3/8 WH X 2" SOCKET SETSCREW 185 In Stock for despatch	£271.11 (exc VAT) per HUND £325.33 (inc VAT)	- +
SKSTW044050	7/16 WH X 1/2 SOCKET SETSCREW Out of Stock	Price Unavailable	- +
SKSTW044050P	7/16 WH X 1/2 SOCKET SETSCREW ZINC PLATED Out of Stock	£243.70 (exc VAT) per HUND £292.44 (inc VAT)	- +
SKSTW044075	7/16 WH X 3/4 SOCKET SETSCREW Out of Stock	Price Unavailable	- +
SKSTW044100	7/16 WH X 1" SOCKET SETSCREW Out of Stock	£230.70 (exc VAT) per HUND £276.84 (inc VAT)	- +
SKSTW050050	1/2 WH X 1/2 SOCKET SETSCREW 100 In Stock for despatch	£150.10 (exc VAT) per HUND £180.12 (inc VAT)	- +
SKSTW050062	1/2 WH X 5/8 SOCKET SETSCREW 10 In Stock for despatch	Price Unavailable	- +
SKSTW050075	1/2 WH X 3/4 SOCKET SETSCREW 56 In Stock for despatch	£155.80 (exc VAT) per HUND £186.96 (inc VAT)	- +
SKSTW050075P	1/2 WH X 3/4 SOCKET SETSCREW ZINC PLATED Out of Stock	£237.70 (exc VAT) per HUND £285.24 (inc VAT)	- +
SKSTW050100	1/2 WH X 1" SOCKET SETSCREW 45 In Stock for despatch	£255.20 (exc VAT) per HUND £306.24 (inc VAT)	- +
SKSTW050125	1/2 WH X 1.1/4 SOCKET SETSCREW 36 In Stock for despatch	£98.09 (exc VAT) per HUND £117.71 (inc VAT)	- +
SKSTW050150	1/2 WH X 1.1/2 SOCKET SETSCREW Out of Stock	Price Unavailable	- +
SKSTW050200	1/2 WH X 2" SOCKET SETSCREW 8 In Stock for despatch	Price Unavailable	- +
SKSTW050250	1/2 WH X 2.1/2 SOCKET SETSCREW 10 In Stock for despatch	Price Unavailable	- +
SKSTW050300	1/2 WH X 3" SOCKET SETSCREW Out of Stock	£2,200.70 (exc VAT) per HUND £2,640.84 (inc VAT)	- +
SKSTW062062	5/8 WH X 5/8 SOCKET SETSCREW Out of Stock	£243.00 (exc VAT) per HUND £291.60 (inc VAT)	- +
SKSTW062075	5/8 WH X 3/4 SOCKET SETSCREW Out of Stock	Price Unavailable	- +
SKSTW062100	5/8 WH X 1" SOCKET SETSCREW Out of Stock	£423.40 (exc VAT) per HUND £508.08 (inc VAT)	- +
SKSTW062125	5/8 WH X 1.1/4 SOCKET SETSCREW Out of Stock	Price Unavailable	- +
SKSTW062150	5/8 WH X 1.1/2 SOCKET SETSCREW 2 In Stock for despatch	Price Unavailable	- +
SKSTW062200	5/8 WH X 2" SOCKET SETSCREW 33 In Stock for despatch	£776.77 (exc VAT) per HUND £932.12 (inc VAT)	- +
SKSTW062250	5/8 WH X 2.1/2 SOCKET SETSCREW Out of Stock	£773.10 (exc VAT) per HUND £927.72 (inc VAT)	- +
SKSTW075075	3/4 WH X 3/4 SOCKET SETSCREW Out of Stock	£3,214.40 (exc VAT) per HUND £3,857.28 (inc VAT)	- +
SKSTW075150	3/4 WH X 1.1/2 SOCKET SETSCREW Out of Stock	£3,348.87 (exc VAT) per HUND £4,018.64 (inc VAT)	- +
SKSTW075200	3/4 WH X 2" SOCKET SETSCREW Out of Stock	£1,553.80 (exc VAT) per HUND £1,864.56 (inc VAT)	- +
SKSTW075250	3/4 WH X 2.1/2 SOCKET SETSCREW 3 In Stock for despatch	£1,150.00 (exc VAT) per HUND £1,380.00 (inc VAT)	- +
SKSTW087200	7/8 WH X 2" SOCKET SETSCREW Out of Stock	£1,362.30 (exc VAT) per HUND £1,634.76 (inc VAT)	- +
SKSTW100150	1" WH X 1.1/2 SOCKET SETSCREW Out of Stock	£8,570.00 (exc VAT) per HUND £10,284.00 (inc VAT)	- +

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