mating screws and nuts_t14u

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T 14 ver b2a Mating screws and nuts Nuts of a higher property class can nomally be used in the place of nuts of a lower property class. * Property classes 14.9 are not ISO or ANSI standard = quenched and tempered Property classes bolts, screws, studs 3.6 4.6 4.8 5.6 5.8 6.8 8.8 9.8 10.9 12.9 14.9 Property classes nuts 5 6 8 9 10 12 14 Property classes The symbol for the property classes of bolts, screws and studs consists of two numbers separated by a point. The first number, when multiplied by one hundred, indicates the nominal tensile strength in newtons per square millimeter. The second figure, multi- plied by ten, states the ratio between the lower yield stress and the nominal tensile strength (yield stress ratio) as a percentage. The multiplication of these two figures will give one tenth of the yield stress in newtons per square millimeter. Example of a screw in property class 5.8 Nominal tensile strength 5 ¥ 100 = 500 N/mm 2 (MPa) Yield stress ratio 8 ¥ 10 = 80% Yield stress 80% of 500 = 400 N/mm 2 (MPa) For nuts, the main characteristic property is the thread stripping strength (proof stress). The property classes of nuts are designated by a figure to indicate the maximum appropriate property class of bolts with which they may be mated. Thus, nut property class is the same as the first figure of the bolt designation. Internationally, mechanical stress is ex- pressed in newtons per square area, in bolting N/mm 2 . US practice is to use the term megapascal (MPa), which correspond to N/mm 2 . Ex. 500 /mm 2 = 500 MPa In this cataloque the term N/mm 2 is used only. MARYLAND METRICS P.O.Box 261 Owings Mills, MD 21117 USA (410)358-3130 (800)638-1830 Faxes: (410)358-3142 (800)872-9329 http://mdmetric.com [email protected] TECHNICAL INFORMATION and DATA

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Tolerance of thread of screw

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Page 1: Mating Screws and Nuts_T14u

T 14 ver b2a

Mating screws and nuts

Nuts of a higher property class can nomally be used in the place of nuts of a lowerproperty class.

* Property classes 14.9 are not ISO or ANSI standard

= quenched and tempered

Property classesbolts, screws, studs 3.6 4.6 4.8 5.6 5.8 6.8 8.8 9.8 10.9 12.9 14.9

Property classesnuts 5 6 8 9 10 12 14

Property classesThe symbol for the property classes of bolts,screws and studs consists of two numbersseparated by a point. The first number, whenmultiplied by one hundred, indicates thenominal tensile strength in newtons persquare millimeter. The second figure, multi-plied by ten, states the ratio between thelower yield stress and the nominal tensilestrength (yield stress ratio) as a percentage.The multiplication of these two figures willgive one tenth of the yield stress in newtonsper square millimeter.

Example of a screw in property class 5.8

Nominal tensile strength5 ¥ 100 = 500 N/mm2 (MPa)

Yield stress ratio 8 ¥ 10 = 80%

Yield stress 80% of 500 = 400 N/mm2 (MPa)

For nuts, the main characteristic property isthe thread stripping strength (proof stress).

The property classes of nuts are designatedby a figure to indicate the maximumappropriate property class of bolts with whichthey may be mated. Thus, nut property classis the same as the first figure of the boltdesignation.

Internationally, mechanical stress is ex-pressed in newtons per square area, in bolting N/mm2. US practice is to use the termmegapascal (MPa), which correspond toN/mm2

.

Ex. 500 /mm2 = 500 MPa

In this cataloque the term N/mm2 is used only.

MMAARRYYLLAANNDD MMEETTRRIICCSSP.O.Box 261 Owings Mills, MD 21117 USA

(410)358-3130 (800)638-1830 Faxes: (410)358-3142 (800)872-9329http://mdmetric.com [email protected]

TECHNICAL INFORMATION and DATA