Copper Tube Information

Company dynamics

12x1.75 brass female tub drain bolt

author:MF manufacturerstime:2022-03-15 23:11:50

12x1.75 brass female tub drain bolt

one、Bolt performance level

a.Steel structure connection bolt performance grade3.6、4.6、4.8、5.6、6.8、8.8、9.8、10.9、12.9Wait10Level,in8.8Level and above bolts are low carbon alloy steel or medium carbon steel and heat treatment(Quench、Temper),Ten high strength bolt,The rest is known as ordinary bolts。Bolt performance rating label has two part numbers,Nominal tensile strength value and flexor ratio of bolt material respectively。

General bolts are used"X.Y"Indicate strength

X*100=This bolt tensile strength

X*100*(Y/10)=Yield strength of this bolt

E.g,Performance level4.6Level bolt,Its meaning is:

1、Bolt material Nominal tensile strength400MPaclass;

2、The flexor ratio of the bolt material is0.6;

3、Name yield strength of bolt material400×0.6=240MPaThe meaning of bolt performance rating is the international general standard,Bolts of the same performance level,Regardless of its material and origin,Its performance is the same,Use only performance grades in design。Strength grade so-called8.8Level and10.9Level is the shear stress grade of bolts8.8GPaand10.9Gpa

12x1.75 brass female tub drain bolt

b.Stainless steel bolt common level:Stainless steel60,70,80(Austenite);

50,70,80,110(Martensite);45,60(Tie)Three categories。

(12x1.75 brass female tub drain bolt)E.g,Performance levelA2-70Bolt,Its meaning is:

(12x1.75 brass female tub drain bolt)1、strength levelArepresent”Austenite”;


3、70Representative strength grade is700MPa;

Common materials areA2andA4,Be304and316Material,But as long as you can guarantee mechanical properties,Chemical composition can have been put in.

12x1.75 brass female tub drain bolt

two、Thread-fit grade:

(12x1.75 brass female tub drain bolt)Thread fit is a loose size between spinning threads,The grade of the mating is a set of specified combinations that act on both internal and external threads and tolerances。

(one)、Unified British thread,Three thread grades:1A、2Aand3Aclass,Three levels of internal threads:

1B、2Band3Bclass,All are gaps。The higher the rank number,Teamwork。Incomputory,Deviation only1Aand2Aclass,3ALevel deviation is zero,and1Aand2ALevel grade deviation is equal。

(12x1.75 brass female tub drain bolt)The bigger the number of tolerances, the smaller the tolerance。

1、1Aand1Bclass,Very loose tolerance level,It is suitable for the tolerance of internal and external threads。

(12x1.75 brass female tub drain bolt)2、2Aand2Bclass,It is the most common thread tolerance level for the British series mechanical fasteners.。

3、3Aand3Bclass,Circular formation,Suitable fasteners for tolerance,Key design for security。

(two)、Metric thread,Three thread grades:4h、6hand6g,The internal thread has three thread grades:5H、6H7H。(Daily standard score is divided intoⅠ、Ⅱ、ⅢLevel three,UsuallyⅡclass)In the metric thread,HandhBasic deviation is zero。GBasic deviation is positive,e、fandgBasic deviation is negative。as the picture shows:

1、HIt is a tolerance zone commonly used in internal threads,Generally not used as a surface plating,Or use very thin phosphating layer。GBasic deviations for special occasions,Thick coating,Generally used。

2、gCommonly plated6-9umThin plating,If the product drawing requirements are6hBolt,Its plating thread6gTolerance band。

3、Both threads are best combinedH/g、H/horG/h,For bolts、Refined fasteners such as nuts,Standard recommendation6H/6gCooperation。

12x1.75 brass female tub drain bolt