TEST PROCEDURE FOR THE PERFORMANCE
OF METRIC ADHESIVE COATED PREVAILING-TORQUE SCREWS
Published and issued by the Industrial Fasteners Institute of Independence, OH
IFI
STANDARD ®
Issued:1982
Revid: Aug. 1, 2007
IFI-525
•ASME B1.3M, Screw Thread Gaging Sys-tems for Dimensional Acceptability — Inch and Metric Screw Threads (UN, UNR, UNJ, M, and MJ).•ASME B1.13M, Metric Screw Threads —
M Profile
•ASME B18.2.4.1M, Metric Hex Nuts, Style 1
•ASME B18.18.2M, Inspection and Quality
Assurance f or H igh-Volume M achine A smbly F asteners 2.2
ASTM Standards.剩饺子怎么做好吃
ASTM standards are available from The Ameri-can Society for Testing and Materials, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959.•ASTM A563, Standard Specification for
Carbon and Alloy Steel Nuts 2.3
ISO Standards.
ISO standards may be obtained from the
International Organization for Standardization, Ca postale 56, CH-1211 Geneva 20, Switzerland •ISO 4032 Hexagon Nuts, Style 1 – Product
Grades A and B 3.0
Designations.
3.1Types. There are two types of adhesive coated screws bad on when the adhesive coating is applied. Preapplied adhesive coatings are applied as part of screw manufacturing prior to delivery for as-mbly. Applied liquid adhesive coatings are applied as part of the asmbly operation or in rvice appli-cations.
3.2Design. The composition and application of the adhesive coating shall be in accordance with the practice of the manufacturer. For applications where temperatures may exceed 93ºC and/or a lubricant is prent or applied for protection or ea of asmbly,an adver effect may result on the prevailing-torque material. The manufacturer's data should be con-sulted to determine suitability of the lection.
1.0
Scope.
1.1This standard establishes a conformance test procedure for the performance of metric adhesive coated prevailing-torque screws in nominal thread diameters M3 thru M20 inclusive.
Torque values given in this standard are
conformance requirements for adhesive coated pre-vailing-torque screws and apply only to the combina-tion of test conditions described in the performance test procedure (Para. 5.1). If the conditions of the actual rvice application differ from tho of Para.5.1 (e.g., length of thread engagement, class of internal thread tolerance, different coating on screw or mating part) the torque values may differ. Such values can only be determined through testing the prevailing-torque screw in its actual asmbly.
维族人This standard is not concerned with dimen-sional features such as head styles, or with other mechanical or performance capabilities such as strength properties, corrosion resistance, aling,suitability for u in high or low temperatures, and/or consistency of torque-to-tension relationships during asmbly. Such features and properties are covered in other standards and specifications, and must be referenced when specifying an adhesive coated pre-vailing-torque screw to ensure that all of the rvice conditions of the particular engineering application are properly met.1.2
Definitions.图腾
1.2.1An adhesive coated prevailing-torque screw (hereinafter called "screw") is an externally threade
d fastener which is resistant to rotation due to a adhesive coating, and not becau of compressive load developed against the underhead bearing sur-face of the screw or a tensile load developed in the shank of the screw.2.0Referenced Standards.2.1
ASME Standards.
The may be obtained from ASME; Three
Park Avenue; New York, NY 10016-5990.Page 1 of 3
TEST PROCEDURE FOR THE PERFORMANCE
OF METRIC ADHESIVE COATED PREVAILING-TORQUE SCREWS知好色则慕少艾
Published and issued by the Industrial Fasteners Institute of Independence, OH
IFI
STANDARD ®
Issued:1982
Revid: Aug. 1, 2007
IFI-525
Page 2 of 3
NOTES:
1.Prevailing-on torque for screws with liquid coatings applied at the time of
asmbly is esntially zero.
2.Minimum value for any of the available liquid coatings. Higher removal
torques may be obtained through lective choice of liquid coating ud.
NOTE:
Values are bad on nut engagement in chemical area for a distance of one nominal screw diameter.
d
e i l p p a e r P h t i W s w e r c S r o
f s e u l a V e u q r o T 1e l b a T s
g n i t a o C e v i s e h d A m o N e
z i S w e r c S d
时间的脚步n a h c t i P d a e r h T n
O -g n i l i a v e r P e u q r o T m
•N y a w a k a e r B e u q r o T m
•N f
f O -
g n i l i a v e r P e u q r o T m
•N x a M n i M n i M 5.0×3M 6.0×5.3M 7.0×4M 8.0×5M 3.05.07.0151.03.04.08.070.051.03.05.01×6M 52.1×8M 5.1×01M 8.18.25.55.10.4118.00.20.457.1×21M 2×41M 2×61M 5
.2×0
2M 2.711412
26122335
40.701612
2h t i W s w e r c S r o f s e u l a V e u q r o T 2e l b a T d
e i l p p A s
g n i t a o C d i u q i L m o N e
z i S w e r c S d电脑电源怎么查看
n a h c t i P d a e r h T n
O -g n i l i a v e r P e u q r o T m
•N y a w a k a e r B e u q r o T m
•N f
f O -
g n i l i a v e r P e u q r o T m
•N x a M n i M n i M 1×6M 52.1×8M 5.1×01M ———65.00.24.343.00.11.157.1×21M 2×41M 2×61M 5
.2×0
2M ————8.40.68.63
12.10.28.25.5s
e t o N e e S 1
2
Tables 1 & 2 note: Values apply to tho listed. For the perfor-mance using other pitches contact the supplier.
乌龟好养吗TEST PROCEDURE FOR THE PERFORMANCE
OF METRIC ADHESIVE COATED PREVAILING-TORQUE SCREWS
Published and issued by the Industrial Fasteners Institute of Independence, OH
IFI
STANDARD ®
Issued:1982
Revid: Aug. 1, 2007
IFI-525
screw are fully engaged. The highest torque occurring while the test nut is in motion shall be measured and recorded. Speed of rotation shall be approximately 12RPM. Speed of rotation shall not exceed 30 RPM.
After 24 hours at 24ºC (±3º) in the asmbled
condition the breakaway torque of the test nut shall be measured. Breakaway torque is defined as the torque to start rotation in the looning direction. Removal shall be continued and the prevailing-off torque mea-sured and recorded. Prevailing-off torque is defined as the highest removal torque occurring during the next 360º of rotation following breakaway in the looning direction.
5.1.1Test Nut. Test nuts shall conform to the requirements of ASME B18.2.4.1M, Style 1 or ISO 4032, Style 1 having a plain or dry phosphate (oil free)finish. A new test nut shall be ud for testing each screw. Prior to u, the threads of each of the test nut (Class 6H thread) shall be inspected for acceptability following the requirements of Gaging System 21 of ASME B1.3M.
Refer to ASME B18.18.2M for sampling plan
(Table 3, destructive, Level A).6.0
Inspection.
6.1Inspection Procedure. Screws shall be inspected to determine conformance with the requirements of this standard.
Unless otherwi specified, from each lot of
screws the following number of tests shall be con-ducted to determine the acceptability of each of the requirements:
Page 3 of 3
4.0
Requirements.
4.1Finish. Screws shall be furnished plain or with a protective coating as specified by the pur-char.4.2
Threads.
4.2.1Thread Tolerances. Threads of prevailing-torque screws shall be tolerance class 6g as specified in ASME B1.13M.
4.2.2 Thread Start. Screws shall asmble a minimum of one full turn by hand into any mating internally threaded component before engaging the coating that has threads acceptable to Gaging Sys-tem 21 of ASME B1.3M.4.3
Performance.
4.3.1The prevailing-torque of screws occurring during the first installation shall not exceed the maximum prevailing-on torque specified in Table 1 or Table 2, as applicable, when tested as specified in Para.
5.1. In addition, the breakaway torque and highest prevailing-off torque occurring during the first removal shall not be less than minimum torques specified in Table 1 and Table 2, as applicable, when tested in accordance with Para. 5.1.
4.3.2Prevailing-Torque. Screws which are too short or which have thread lengths too short to permit testing in accordance with Para.
5.1, shall have their torque requirements and test procedure established by agreement between the purchar and manufacturer.5.0
Performance Test.
5.1Test Procedure. The sample screw shall be asmbled into the countersunk side of a test nut (Para. 5.1.1). During the performance of the test, the nut shall be turned using manual torque only,
while the test screw shall be restrained from turning. The nut shall be advanced until the coated threads of the
)s e c e i p (e z i S t o L s
t s e T f o .o N 05o t 005o t 15000,53o t 1050
00,53r e v o 2358
Alternate inspection procedures may be
年休假规定
specified by the purchar on the purcha order or engineering drawing.
