Abstract： ASME B1.1:2019 pdf download.Unified Inch Screw Threads (UN,UNR, and UNJ Thread Forms). 2.4 Formulas and Nomenclature The formulas and nomenclature pertaining to the basic profile and the design profiles are given in section 10. 3 SCREW THRE...

ASME B1.1:2019 pdf download.Unified Inch Screw Threads (UN,UNR, and UNJ Thread Forms).

2.4 Formulas and Nomenclature

The formulas and nomenclature pertaining to the basic profile and the design profiles are given in section 10.

3 SCREW THREAD SERIES

3.1 Thread Series Definition

Thread series are groups of diameter-pitch combinations distinguished from each other by the number of threads per Inch applied to a series of specific diameters. There are two general series classifications: standard and special.

3.1.1 Standard Series. The standard series consists of

three series with graded pitches (coarse, fine, and extra

fine) and eight series with constant pitches (4,6.8. 12, 16,

20. 28. and 32 threads per inch). The standard series is

shown In Table 1. Limitsolsizeare shown In Tables ZAand

28 and discussed In section 8.

3.1.2 Speclat Series. The special series consists of all threads with diameter-pitch combinations that are not included in the

standard series. When allowances and tolerances of special series threads arc derived from unified formulation as shown in

section 5, the threads are designated UNS. UNIS. or UNRS. If allowance and toler• ance are not derived from unified formulation,

the threads are designated SPL 60•deg Form.” (Sec para. 6.1 and FIgure 13 for details of designation.)

3.2 Order of SeLection

Wherever possible, selection should be made Irorn Table 1, preference being given to the coarse- and fine-thread series. As second choice, if the threads in the standard series in Table 1 do not meet the requirements ofthe design, special thread sizes should be selected from Table E-1 and their limits calculated using the formulas in section 8. The limits in Table 0-1 are for reference only and are not recommended for new applications.

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