中文版The first chapter measure
Now in the world the length Measuring unit mainly has two kinds, one kind is the metric system, the Measuring unit for the rice (m), the centimeter (cm), the millimeter (mm) and so on, in Southeast Asia uses and so on Europe, our country and Japan are many, another kind is the British system, the Measuring unit mainly for the inch (inch), is equal in our country old system’s city inch, in European and American countries uses and so on US, Britain are many.
1st, metric measurement: (10 enter system)
1m =100 cm=1000 mm
2nd, British system measurement: (8 enter system)
1 inch =8 UK divides 1 inch =25.4 mm3/8¢¢×25.4 =9.52
3rd, 1/4¢¢ the following product expresses its name diameter with the designation, for example: 4#,5#,6#,7#,8#,10#,12#
The second chapter thread
First, the thread is one kind in the solid outside surface or on the internal surface section, has the even spiral line bulge shape. May divide into three broad headings according to its unique feature and the use:
(one), plain thread: The tooth shape is a triangle, uses in connecting or the fastening parts. The plain thread divides into the coarse thread and the fine thread two kinds according to the pitch, the fine thread joint strength is high. ((two), transmission thread: The tooth shape has the trapezoid, the rectangle, the sawtooth and the triangle and so on.
(three), seal thread: Uses in sealing the connection, is mainly is effective the thread, the awl thread and the awl pipe thread.
Second, thread grade of fit:
The thread coordination is turns on lathe gathers between the thread the pine or the tight size, the coordinate rank is the function in the inside and outside thread upper deviation and the common difference stipulation combination.
(one), to the unified inch thread, the external screw thread has three kind of thread ranks: 1A, 2A and the 3A level, the box thread has three ranks: 1B, 2B and the 3B level, is the clearance fit completely. The rank digit is higher, the coordination is tighter. In the inch thread, the deviation only stipulated that 1A and the 2A level, the 3A level’s deviation is zero, moreover 1A and the 2A level’s rank deviation is equal.
A rank number bigger common difference is smaller, like the chart shows:
1st, 1A and the 1B level, the very loose grade of tolerance, it is suitable for the inside and outside thread allowable deviation coordination.
2nd, 2A and the 2B level, is the British system series mechanical fastener stipulates the most general thread tolerance rank.
3rd, 3A and the 3B level, turns on lathe gathers forms the tightest coordination, is suitable in the common difference tight fastener, uses in the secure key design.
4th, the foreign thread, 1A and the 2A level has a tolerance on fit, the 3A level does not have. 1A level common difference compared to 2A level common difference big 50%, compared to the 3A level big 75%, the internal thread, the 2B level common difference compared to the 2A common difference big 30%. 1B level compared to the 2B level big 50%, compared to the 3B level big 75%.
(two), the metric thread, the external screw thread has three kind of thread ranks: 4h, 6h and 6g, the box thread has three kind of thread ranks: 5H, 6 H, 7H. (date sign thread precision class divides into I, II, III third-level, usually under condition is II level) in the metric thread, H and the h basic deviation is zero. The G basic deviation is just, e, f and the g basic deviation is a negative value. Like the chart shows:
H is the box thread commonly used tolerance zone position, generally does not serve as superficial coating, or uses the extremely thin phosphorization level. The G position basic deviation uses in the special occasion, if thick coating, very little uses generally.
2nd, g often uses for to plate 6-9um the lightly coated level, if the product blueprint request is the 6h bolt, before it plates, the thread to use 6g the tolerance zone.
3rd, the thread coordination is best combines H/g, H/h or G/h, regarding purification fastener threads and so on bolt, nut, the standard recommendation uses 6H/6g the coordination.
(three), thread mark
Third, mechanical thread main geometric parameter:
(one), great diameter/tooth outer diameter (D, d): For external screw thread crest or in root of thread superposition ideal cylinder diameter. Thread great diameter basic representative thread size nominal diameter.
(two), pitch diameter (D2, d2): D2=d2=D (d) - 2x3H/8, in the formula H is the primitive triangle is high: H= (√3 /2) P=0.866025P (60O tooth mountain angle; H=0.960491P (55 O tooth Shan Jia)
(three), trail/tooth bottom diameter (D1, d1): Ideal cylinder’s diameter which superpose for the external screw thread crest or the box thread crest.
(four), pitch (P): Corresponds two spots for the neighboring of tooth on the diameteral wire distance between the axial distances either the neighboring tooth mountain or two neighboring tooth valley. In the British system by each inch (25.4 mm) in tooth number indicated that pitches (the following table).
|
Specification |
Pitching |
Specification |
Calling Shouting Diameter |
Tooth number | ||||||
|
Coarse thread |
Fine thread |
Extremely fine thread |
Coarse thread |
Fine thread |
Webster tooth | |||||
|
M3 |
0.5 |
0.35 |
4# |
2.9 |
40 |
48 |
||||
|
M4 |
0.7 |
0.5 |
6# |
3.5 |
32 |
40 |
||||
|
M5 |
0.8 |
0.5 |
8# |
4.2 |
32 |
36 |
||||
|
M6 |
1.0 |
0.75 |
10# |
4.8 |
24 |
32 |
||||
|
M7 |
1.0 |
0.75 |
12# |
5.5 |
24 |
28 |
||||
|
M8 |
1.25 |
1.0 |
0.75 |
1/4 |
6.35 |
20 |
28 |
20 | ||
|
M10 |
1.5 |
1.25 |
1.0 |
5/16 |
7.94 |
18 |
24 |
18 | ||
|
M12 |
1.75 |
1.5 |
1.25 |
3/8 |
9.53 |
16 |
24 |
16 | ||
|
M14 |
2.0 |
1.5 |
1.0 |
7/16 |
11.11 |
14 |
20 |
14 | ||
|
M16 |
2.0 |
1.5 |
1.0 |
1/2 |
12.7 |
13 |
20 |
12 | ||
|
M18 |
2.5 |
2.0 |
1.5 |
9/16 |
14.29 |
12 |
18 |
12 | ||
|
M20 |
2.5 |
2.0 |
1.5 |
5/8 |
15.86 |
11 |
18 |
11 | ||
|
M22 |
2.5 |
2.0 |
1.5 |
3/4 |
19.05 |
10 |
16 |
10 | ||
|
M24 |
3.0 |
2.0 |
1.5 |
7/8 |
22.23 |
9 |
14 |
9 | ||
|
M27 |
3.0 |
2.0 |
1.5 |
1 |
25.40 |
8 |
12 |
8 | ||
|
M30 |
3.5 |
3.0 |
2.0 |
|||||||
(five), tooth half-angle (α/2): The tooth side and between the thread spool thread’s included angle perpendicular line’s, the plain thread tooth half-angle is 60O/2, the Webster tooth (BSW) the thread tooth half-angle is 55O/2. Generally the wood screw tooth mountain angle is 60 O, tail point angle 60O.
(six), the thread turns on lathe gathers the length: For two coordinate the thread, turns on lathe mutually along the thread axis direction gathers the part the length.
Fourth, from attacks, from drills the thread the main geometric parameter:
1st, great diameter/tooth outer diameter (d1), for crest of screw thread superposition ideal cylinder diameter. Thread great diameter basic representative thread size nominal diameter.
2nd, trail/tooth bottom diameter (d2): For root of thread superposition ideal cylinder diameter. , pitches (p): Corresponds two spots for the neighboring tooth in the warp the axial distances. (25.4 mm) in tooth number indicates in the British system by each inch pitches.
The next table enumerates the commonly used specification to pitch (metric system) the tooth number (British system)
1st, the metric system from attacks the tooth:
|
Specification |
S T 1.5 |
S T 1.9 |
S T 2.2 |
S T 2.6 |
S T 2.9 |
S T 3.3 |
S T 3.5 |
S T 3.9 |
S T 4.2 |
S T 4.8 |
S T 5.5 |
S T 6.3 |
S T 8.0 |
S T 9.5 |
|
Pitching |
0.5 |
0.6 |
0.8 |
0.9 |
1.1 |
1.3 |
1.3 |
1.3 |
1.4 |
1.6 |
1.8 |
1.8 |
2.1 |
2.1 |
2nd, the British system from attacks the tooth:
|
Specification |
4# |
5# |
6# |
7# |
8# |
10# |
12# |
14# | |
|
Tooth Number |
AB tooth |
24 |
20 |
20 |
19 |
18 |
16 |
14 |
14 |
|
A tooth |
24 |
20 |
18 |
16 |
15 |
12 |
11 |
10 | |
3rd, date sign wall plate nail:
|
Specification |
6# |
7# |
8# |
10# | |
|
Coarse thread |
Tooth number |
9 |
9 |
9 |
8 |
|
Pitching |
2.82 |
2.82 |
2.82 |
3.18 | |
|
Fine thread |
Tooth number |
18 |
16 |
15 |
12 |
|
Pitching |
1.41 |
1.59 |
1.69 |
2.11 | |
4th, mechanical screw (mechanical tooth):
|
Specification |
The metric system (pitches) |
British system (tooth number) | ||||||||||||
|
M2.5 |
M3 |
M3.5 |
M4 |
M5 |
M6 |
M8 |
4# |
5# |
6# |
8# |
10# |
12# |
1/4 | |
|
Coarse thread |
0.45 |
0.5 |
0.6 |
0.7 |
0.8 |
1.0 |
1.2 |
40 |
40 |
32 |
32 |
24 |
24 |
20 |
|
Fine thread |
0.35 |
0.35 |
0.35 |
0.5 |
0.5 |
0.75 |
1.0 |
48 |
44 |
40 |
36 |
32 |
28 |
28 |
5th, drills the tail screw: Drills the tail screw to have CSD (mechanical tooth), BSD (from attacks the AB tooth) two kinds. It pitches or the tooth number may refer to the mechanical screw separately (the CSD tooth) and from the tapping (the BSD tooth).
(four), tooth mountain angle and tail point angle: Tooth Shan Jiawei the tooth side and the tooth side’s included angle, the tail acute angle has not carried the acute angle for the thread.
1st, from attacks the tooth: The tooth mountain angle is 60O, the tail point angle is 45 O±5 O.
2nd, wall plate nail: The tooth mountain angle is 60O, (may also depend on customer request production, like 45 O±5 O) the tail point angle is 25 O±3O.
3rd, clamping plank nail: (Chip board screws) the tooth mountain angle is 40 O±3 O, the tail point angle for 25O±3 O or 34O±3O (customer special request).
4th, drills the tail screw: The tooth mountain angle is 60 O±5 O, the rear part selects the different model in view of the different specification product to clamp the tail needle, clamps tail’s main geometric parameter to clamp the tail diameter and to stretch out the quantity.
The third chapter material
First, in the present market the standard letter mainly has the carbon steel, the stainless steel, the copper three materials.
(one) carbon steel. We foresee accurately the carbon by the carbon steel the content to differentiate the low-carbon steel, the medium carbon steel and the high-carbon steel as well as the alloy steel.
1st, the low-carbon steel C%≤0.25% homes usually are called a3 steel. Overseas is called 1008,1015,1018,1022 and so on basically. Mainly uses in 4.8 levels of bolts and 4 levels of nuts, the small screw and so on non-degree of hardness request product. (note: Drills the tail nail mainly to use 1022 materials. )
2nd, the medium carbon steel 0.25%<C%≤0.45% homes usually are called 35, 45 steel, overseas is called 1035, CH38F,1039,40ACR basically and so on. Mainly uses in 8 levels of nuts, 8.8 levels of bolts and 8.8 level in hexagonal products.
3rd, high-carbon steel C%>0.45%. At present in the market basic has not used
4th, alloy steel: Joins the alloying element in the Pu carbon steel, increases the steel products some special performances: Like 35, 40 chromium molybdenum, SCM435,10B38. Lives the screw mainly to use the SCM435 chromium molybdenum alloy steel fragrant, the principal constituent has C, Si, Mn, P, S, Cr, Mo.
(two) stainless steel. Performance rating: 45,50,60,70,80
The main minute austenite (18%Cr, 8%Ni) the thermal stability is good, the inoxidizability is good, the weldability is good. A1, A2, A4 martensite, the 13%Cr inoxidizability is bad, the intensity is high, the resistance to wear is good. C1, C2, C4 ferritic stainless steel. 18%Cr dui hammers the nature to be good, inoxidizability strong in martensite. At present in the market the imported material is mainly the Japanese product. According to rank main minute SUS302, SUS304, SUS316.
(three) copper. The commonly used material is the brass…Zinc copper alloy. In the market mainly with H62, H65, the H68 copper makes the standard letter.
Second, the carbon steel product uses wire rod:
|
Serial number |
Type |
May select material quality |
|
1 |
4.8 level of hexagon bolts |
1008K 1010 1015K |
|
2 |
6.8 level of hexagon bolts |
1032 1035 1040 CH38F 1039 |
|
3 |
8.8 level of hexagon bolts |
1035ACR (below M10) 1040ACR (above M12) CH38F 1045ACR 1039 10B21 10B33 10B38 |
|
4 |
8.8 level in hexagon bolts |
CH38F 1039 10B21 (M10-M12) 10B33 (M14) 10B38 (M12-M24) 10B21 |
|
5 |
10.9 level of hexagon bolts |
1045ACR10B38 |
|
6 |
│8│ level cap nut |
1008K 1010 |
|
7 |
8 levels of cap nuts |
1015(M<16) CH38F (M≥16) |
|
8 |
10 levels of cap nuts |
CH38F 1039 10B21 10B33 |
|
9 |
12 levels of cap nuts |
1039 10B21 10B33 10B38 |
|
10 |
Horse-drawn vehicle screw |
1008 1010 1015 |
|
11 |
Six square staff raised bolts |
CH38F 1039 10B21 10B33 10B38 |
|
12 |
Hexagonal wood screw |
1008K1010 |
|
13 |
From attacks the nail, the wall plate nail Drills the tail nail, the clamping plank nail |
10181022CH22A |
Third, in material each kind of element to steel nature influence:
1st, carbon (C): Enhances the steel stock intensity, particularly its heat treatment performance, but along with carbon amount increase, the plasticity and toughness drops, and will affect steel stock Leng Dui the performance and the welding performance.
2nd, manganese (Mn): Enhances the steel stock intensity, and enhances the hardening capacity to a certain extent. Namely when quenching increased the hard permeating intensity, the manganese has also been able to improve the surface quality, but too many manganese were disadvantageous to the ductility and the weldability. And will affect when the galvanization will coat control.
3rd, nickel (Ni): Enhances the steel stock intensity, improves under the low temperature toughness, enhances bears the atmospheric corrosion ability, and may guarantee that the stable heat treatment effect, reduces the hydrogen embrittlement the function.
4th, chromium (Cr): Can enhance the hardening capacity, the improvement resistance to wear, sharpens the anti-corrosive ability, and is advantageous under the high temperature maintains an intensity.
5th, molybdenum (Mo): Can help the control hardening capacity, reduces the steel to the temper brittleness sensitivity, to enhances under high temperature the tensile strength to have the very tremendous influence.
6th, boron (B): Can enhance the hardening capacity, and is helpful in causes the low-carbon steel to have the anticipated response to the heat treatment.
7th, vitriol (V): Refinement austenite crystal grain, improvement toughness.
8th, silicon (Si): Guaranteed that the steel stock the intensity, the suitable content may improve the steel stock plasticity and toughness.
Fourth, characteristic of synopsis about stainless steel material quality (304, 316)
These three kind of material qualities are 300 series austenite stainless steel, its chemical composition is as follows:
|
Name |
C |
Si |
Mn |
P |
S |
Ni |
Cr |
Mo |
Cu |
|
304M |
≤0.06 |
≤1.0 |
≤2.0 |
≤0.045 |
≤0.03 |
8.91-10.0 |
18.0-20.0 |
0 |
0 |
|
316 |
≤0.03-0.06 |
≤1.0 |
≤2.0 |
≤0.045 |
≤0.03 |
10.0-14.0 |
16.0-18.0 |
2.0-3.0 |
0 |
|
304HC |
≤0.08 |
≤1.0 |
≤2.0 |
≤0.045 |
≤0.03 |
8.0-10.5 |
17.0-19.0 |
0 |
1.0-3.0 |
Relations of main of chemical composition and the stainless steel performance.
1st, carbon C may the hardening and the intensity, the content is excessively high will reduce its ductility and the corrosion resistance
2nd, chromium Cr may increase the corrosion resistance, the oxidation resistance, causes a grain of refinement, the gain in strength, degree of hardness and the resistance to wear
3rd, nickel Ni may increase the strength at high temperatures, the corrosion resistance, cuts speed of the cold finishing hardening
4th, molybdenum Mo the gain in strength, is fine to the oxide compound and the sea water corrosion resistance
5th, copper Cu favors the cold finishing formation, reduces magnetism
(three) material quality other performance
1st, above material quality normal state nonmagnetic. after 304M cold finishing, slightly magnetic (about 1.6u-2.0u); the 304HC magnetism is (about 1.01u-1.6u); after 316 material quality cold finishings, magnetism is smaller than 1.01u.
2nd, various material qualities have the good ductility, the easy cold finishing formation, the tensile strength, the yield strength, to be possible to meet the requirements. (Ts tensile strength min700N/mm, Ys yield strength min 450N/mm)
(four) conclusion
1st, 304M, 304HC, 3163 kind of material qualities are the present 300 series austenite stainless steel use one of broadest material qualities. The various material qualities obvious difference is: After the cold finishing, material quality magnetism is 316<304HC<304M. 316 material quality anti-chemicals corrode, anti-Kong Shixing and the anti-sea water anticorrosion performance is opposite in 304M and 304HC must be fine.
2nd, in brief, stainless steel standard letter characteristic for anti-corrosive, artistic, health, therefore but in its intensity, the degree of hardness normal condition is equal in the carbon steel (6.8 levels) should not be possible to hit, strikes, the attention to maintain its surface smooth finish, the precision to the stainless steel product, and cannot be equally casual with the use carbon steel product exerts the strength, may also not the application of force be oversized, because simultaneously the stainless steel ductility is good, when use produces the cast steel filings easily to stick in the cap nut tooth level place, increases the Moroccan cha strength, easy to cause to deadlock, but uses the carbon steel, even if will produce the iron filings also to fall, will be opposite is not easy in the stainless steel to deadlock.
