Standard No.:	GB/T 1181-1998
English Name:	The interference-fit threads
Chinese Name:	过盈配合螺纹
Chinese Classification:	J04    Basic standards and general methods
Professional Classification:	GB    National Standard
Source Content Issued by:	State Quality and Technology Supervision Bureau
Issued on:	1998-08-28
Implemented on:	1999-7-1
Status:	valid
Superseding:	GB 1181-1974
Target Language:	English
File Format:	PDF
Word Count:	4000 words
Translation Price(USD):	100.0
Delivery:	via email in 1 business day

1 Scope This standard specifies the profiles, diameter and pitch series, tolerances, screwing length, technical requirements, assembly torques and symbols of the interference-fit threads. This standard is applicable to double end steel studs with an interference fit in the pitch diameter of thread, and the internal thread of the machine body is made of aluminum alloy, magnesium alloy, titanium alloy and steel. See Annex A (Normative) for the tolerances of the non-ferrous metal studs screwed into the interference-fit threads of an aluminum or magnesium alloy body. 2 Normative References The following normative document contains provisions which, through reference in this text, constitute provisions of this standard. At the time of publication, the edition indicated was valid. All standards are subject to revision, and parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent edition of the standard indicated below. GB/T 192-1981 General Purpose Metric Screw Threads — Basic Profile GB/T 197-1981 General Purpose Screw Threads — Tolerances and Fits for Diameter from 1 to 355 mm GB/T 14791-1993 The Terms of Screw Threads 3 Definitions The terms of screw threads used in this standard shall be in conformity with GB/T 14791. 4 Profile Basic profiles of screw threads shall be in accordance with the requirements given in GB/T 192. The profile design of external thread is a smooth connection curve, the requirements of the profile bottom arc shall be in accordance with the requirements of GB/T 197 for property class higher than class 8.8 fastener thread root, and the minimum radius of the profile bottom arc shall not be less than 0.125 P.

Foreword II 1 Scope 2 Normative References 3 Definitions 4 Profile 5 Diameter and Pitch Series 6 Basic Size 7 Tolerance 8 Screwing Length 9 Other Technical Requirements for Thread Parts 10 Assembly Quality Requirements 11 Designation Annex A (Normative) The Interference Fit Threads for Nonferrous Metal Studs Annex B (Informative) Calculation Formulae for Thread Tolerance Annex C (Informative) Calculation Formula of Assembly Torque