CN105065410A - High-strength bolt for tension control structure - Google Patents
High-strength bolt for tension control structure Download PDFInfo
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- CN105065410A CN105065410A CN201510436467.5A CN201510436467A CN105065410A CN 105065410 A CN105065410 A CN 105065410A CN 201510436467 A CN201510436467 A CN 201510436467A CN 105065410 A CN105065410 A CN 105065410A
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- 230000007704 transition Effects 0.000 claims abstract description 28
- 238000000034 method Methods 0.000 claims description 18
- 238000010438 heat treatment Methods 0.000 claims description 17
- 230000006698 induction Effects 0.000 claims description 10
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 6
- 239000000956 alloy Substances 0.000 claims description 5
- 238000007669 thermal treatment Methods 0.000 claims description 5
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 3
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 3
- 239000001257 hydrogen Substances 0.000 claims description 3
- 229910052739 hydrogen Inorganic materials 0.000 claims description 3
- 229910052757 nitrogen Inorganic materials 0.000 claims description 3
- 239000001301 oxygen Substances 0.000 claims description 3
- 229910052760 oxygen Inorganic materials 0.000 claims description 3
- 238000003754 machining Methods 0.000 claims description 2
- 238000013461 design Methods 0.000 abstract description 8
- 238000012545 processing Methods 0.000 abstract description 6
- 239000000463 material Substances 0.000 abstract description 3
- 238000003672 processing method Methods 0.000 abstract description 2
- 229910000831 Steel Inorganic materials 0.000 description 8
- 239000010959 steel Substances 0.000 description 8
- 238000010791 quenching Methods 0.000 description 5
- 230000000171 quenching effect Effects 0.000 description 5
- 238000005096 rolling process Methods 0.000 description 5
- 238000005496 tempering Methods 0.000 description 5
- 238000005097 cold rolling Methods 0.000 description 3
- 239000012141 concentrate Substances 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 2
- 238000001125 extrusion Methods 0.000 description 2
- 238000003723 Smelting Methods 0.000 description 1
- 229910000754 Wrought iron Inorganic materials 0.000 description 1
- 238000005275 alloying Methods 0.000 description 1
- 238000004873 anchoring Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000005266 casting Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000005261 decarburization Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000004093 laser heating Methods 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 239000011435 rock Substances 0.000 description 1
- 238000007493 shaping process Methods 0.000 description 1
- 230000003746 surface roughness Effects 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 239000002912 waste gas Substances 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
- 239000002351 wastewater Substances 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16B—DEVICES FOR FASTENING OR SECURING CONSTRUCTIONAL ELEMENTS OR MACHINE PARTS TOGETHER, e.g. NAILS, BOLTS, CIRCLIPS, CLAMPS, CLIPS OR WEDGES; JOINTS OR JOINTING
- F16B35/00—Screw-bolts; Stay-bolts; Screw-threaded studs; Screws; Set screws
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D27/00—Foundations as substructures
- E02D27/32—Foundations for special purposes
- E02D27/44—Foundations for machines, engines or ordnance
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Mining & Mineral Resources (AREA)
- Paleontology (AREA)
- Civil Engineering (AREA)
- Structural Engineering (AREA)
- Heat Treatment Of Articles (AREA)
Abstract
The invention relates to a high-strength bolt for a tension control structure. Through setting of the minor diameter of threads, the minor-diameter fillet radius, the thread angles and other sizes, not only is the demand on strength of the bolt met but also the technological requirements of thread processing are satisfied, and transition zones are arranged at the transition parts of threads and a screw, so that cross-section abrupt changes are eliminated, and generation of stress concentration point is avoided. Through design of the screw material and screw processing method, the bolt is relatively high in strength and cannot fracture under the tension condition.
Description
Technical field
The present invention relates to a kind of high-strength bolt, this bolt is applicable to the prestress anchoraging on wind-power generating tower basis, the stretch-draw of bridge, the stretch-draw of large-scale steel structure truss, the anchoring etc. of rock bank protection.
Background technique
the high-strength bolt of wind-power generating tower basis, bridge, large-scale steel structure truss according to requirements and structural requirement, the diameter large (Mt30 ~ Mt64) of high-strength bolt, the body of rod long (3m ~ 12m).Traditional bolt processing technic featuring and existing bolt standard can not meet the requirement of production technology, in order to meet the requirement of structure to the mechanical property of bolt, fracture toughness, fatigue behaviour, relaxation property, boost productivity, reduce cost of production, on the basis of existing bolt standard, with reference to ASTM standard design at the bottom of high, the tooth of the thread form angle of the high-strength bolt of wind-power generating tower basis, bridge, large-scale steel structure truss, pitch, tooth and the parameter such as radius of rounded crest.
this bolt called after tension control structure high-strength bolt, the sublimate making tension control structure high-strength bolt alloy material requires higher, the very long surface that is not easy to of the body of rod due to bolt goes pin to process (not peeling), therefore require very high, it is desirable that the bar of the good free of surface defects of dimensional accuracy to the smelting casting of steel, rolling technique.
because the body of rod of bolt is very long, if the amount of deformation carrying out quenching with Subsequent tempering so bolt to bolt by traditional heat treatment process is very large, particularly the tortuosity of bolt cannot ensure at all, and the intensity of whole support bolt is inconsistent, so adopt induction heating rapid thermal treatment tempering product line to realize the mechanical property requirements of bolt, within the scope of overall length, tortuosity can be controlled within 6 ‰.
the processing of screw thread adopts cold rolling forming technique, the fatigue life impact of surface roughness on bolt of screw thread is very large, rolled thread can improve the degree of finish of thread surface, the particularly degree of finish on screw thread dental groove surface, thus the raising of bolt fatigue strength is conducive to, rolled thread can produce working hardening layer and higher residual compressive stress, cuts much ice to stoping the germinating of fatigue crack and early stage expansion.
Summary of the invention
the object of this invention is to provide a kind of tension control structure high-strength bolt, this bolt, by the screw thread specification of particular design, material and processing method, makes this bolt have higher-strength and can not rupture under stretching force condition.
for solving the problems of the technologies described above, technological scheme of the present invention is as follows:
a kind of tension control structure high-strength bolt, comprise screw rod and the screw thread being arranged on screw rod two ends, described screw thread has following specification:
when Major Diam is 30mm, the pitch of screw thread is 4.0mm, and thread form angle is 50 °, and screw thread height is 2.0mm, and lead angle is 2 ° 36 ', and fillet radius at the bottom of tooth is 0.6mm, and crest radius is 0.4mm, and screw-thread ending transition zone length is 24mm;
when Major Diam is 36mm, the pitch of screw thread is 4.5mm, and thread form angle is 50 °, and screw thread height is 2.2mm, and lead angle is 2 ° 24 ', and fillet radius at the bottom of tooth is 0.8mm, and crest radius is 0.6mm, and screw-thread ending transition zone length is 27mm;
when Major Diam is 42mm, the pitch of screw thread is 5.0mm, and thread form angle is 50 °, and screw thread height is 2.4mm, and lead angle is 2 ° 16 ', and fillet radius at the bottom of tooth is 1.0mm, and crest radius is 0.8mm, and screw-thread ending transition zone length is 30mm;
when Major Diam is 48mm, the pitch of screw thread is 5.5mm, and thread form angle is 50 °, and screw thread height is 2.6mm, and lead angle is 2 ° 13 ', and fillet radius at the bottom of tooth is 1.2mm, and crest radius is 1.0mm, and screw-thread ending transition zone length is 33mm;
when Major Diam is 56mm, the pitch of screw thread is 6.0mm, and thread form angle is 50 °, and screw thread height is 2.8mm, and lead angle is 2 ° 03 ', and fillet radius at the bottom of tooth is 1.4mm, and crest radius is 1.2mm, and screw-thread ending transition zone length is 36mm;
when Major Diam is 64mm, the pitch of screw thread is 6.5mm, and thread form angle is 50 °, and screw thread height is 3.0mm, and lead angle is 1 ° 58 ', and fillet radius at the bottom of tooth is 1.6mm, and crest radius is 1.4mm, and screw-thread ending transition zone length is 39mm;
wherein, described screw-thread ending transition zone refers to and arranges transition zone at the transition position of screw thread and screw rod, and transition zone is progressively transitioned into diameter of thread by effective diameter of thread.
screw thread is in rolling process,, in the external diameter i.e. screw thread of rod iron, warp carries out roll extrusion, pressure position is the bottom of trench of screw thread i.e. the path of screw thread, and the highest portion position of extruding is the large footpath of screw thread, thus transition zone is progressively transitioned into diameter of thread by effective diameter of thread.
make that P content in the alloy material of high-strength bolt should be less than 0.009%, s content should be less than 0.004%, hydrogen content is less than 2mg/m
3
, nitrogen content is less than 12mg/m
3
, oxygen content 10mg/m
3
, c content 0.25 ~ 0.30%, Si content 0.06 ~ 0.08%, Mn content 1.06 ~ 1.07%, Cr content 0.25 ~ 0.27%, Ti content 0.03%, B content is 0.002%.
induction heating is adopted to carry out rapid thermal treatment to screw rod.
adopt roll forming techniques machining screw.
the outstanding mechanical property of tension control structure high-strength bolt of the present invention will lean on ensure at following 3:
1, the requirement of alloy material: the P of alloy material, content should be less than 0.009%, s content should be less than 0.004% hydrogen content and be less than 2mg/m
3,
nitrogen content is less than 12mg/m
3
, oxygen content 10mg/m
3
, c content 0.25 ~ 0.30, Si content 0.06 ~ 0.08, Mn content 1.06 ~ 1.07, Cr content 0.25 ~ 0.27, Ti content 0.03%, B content is 0.002%.The sublimate of tension control structure high-strength bolt steel, low alloying, microalloying ensure that the adaptability of engineering structure part to environment and the obdurability of material from source.
, screw thread cold rolling technique, the design of threads geometrical parameters, ensure that the requirement of strength of bolt and the moulding process requirement of cold rolling, the tooth form of design is similar to trapezoidal, crest width is 2.46 times of regular screw threads crest width, ensure that the integrity of worm tooth in the ball blast technique before anticorrosion.
, the guarantee of mechanical property: the mechanical property reaching tension control structure high-strength bolt realizes on induction heating rapid thermal processing technique prepares, induction heating rapid thermal processing technique can improve uniformity and the stability of steel mechanics performance significantly, reducing oxidation prevents decarburization from improving the surface quality of heat treatment steel, the bolt of two types is at laser heating, quenching, the full-automatic heat treatment production line of tempering completes quenching with Subsequent tempering, in heating quenching process, the running state of bolt is screw type straight line motion, the thread surface of the original precision of bolt can be kept, bolt heats in induction coil, under the high temperature conditions, rarefaction of air in induction coil, bolt heats in air of low density therein media environment, because bolt waiting time under higher than the high temperature condition of 850 DEG C is no more than 8 seconds, bolt surface only forms slight oxide layer, namely bolt maintains original surface accuracy, also ensure that the straightness accuracy of bolt.
the technique effect that the present invention has:
the development of tension control structure high-strength bolt and the use in wind power foundation make the excavated volume of basic earthwork reduce 25%, and quick and easy for installation, cost of labor reduces, and construction period shortens.
tension control structure high-strength bolt heating efficiency when induction heating fast heat treatment device carries out quenching with Subsequent tempering is powerful can realize being rapidly heated energy saving.Accurately can control heat treatment temperature, reduce energy loss.Reduce ambient heat loss and reduce energy consumption.In induction heating rapid thermal treatment process, do not produce waste gas, waste water and waste residue, can not to environment.Induction heating rapid thermal treatment and prior heat treatment process ratio, can save the energy of about 40%, thus decrease atmospheric CO2 emissions, is environmental type heat treatment process.
Accompanying drawing explanation
below in conjunction with accompanying drawing, the present invention will be further described
fig. 1 is the structural representation of high-strength bolt of the present invention;
fig. 2 is the partial enlarged drawing of part A in Fig. 1;
embodiment.
embodiment 1
as shown in Figure 1, a kind of tension control structure high-strength bolt, comprise screw rod and the screw thread being arranged on screw rod two ends, the specification of bolt has 6 kinds, and the Major Diam Mt of requirement is 30mm, 36mm, 42mm, 48mm, 56mm, 64mm respectively, and length is 3m ~ 12m.Intensity rank has two kinds namely 8.8 grades and 10.9 grades, is 4.0mm, 4.5mm, 5.0mm, 5.5mm, 6.0mm, 6.5mm respectively to the pitch of its design of the threaded bolt in two end part; Thread form angle 50 °, screw thread height is 2.0mm, 2.2mm, 2.4mm, 2.6mm, 2.8mm, 3.0mm respectively, and other geometric parameters of bolt are in table one.
wherein,
major Diam Mt refers to the diameter of the ideal cylinder tangent with outside thread crest;
pitch P refers to adjacent two teeth on screw thread at middle axial distance on the bus of cylndrical surface between corresponding 2;
thread form angle α refers in screw thread axial cross section, the angle of thread profile dual-side;
screw thread height h refers to the perpendicular distance of tip of thread and root of thread;
lead angle γ refers to the tangent line of helix on central diameter cylinder and the interplanar angle perpendicular to the axis of thread;
screw-thread ending transition zone refers to and arranges transition zone at the transition position of screw thread and screw rod, is progressively transitioned into diameter of thread by effective diameter of thread d.
specific to bolt connecting body, the screw thread ditch of mechanics factor bolt is the centrostigma of bolt stress under external force, root of thread diameter is more close to round steel diameter during rolling screw-threads, the bearing capacity of bolt is larger, also rolling screw-threads is beneficial to shaping, but thread depth affects not again the intensity of worm tooth, the basis of GB GB/T196-2003 regular screw threads base dimension increases the thread pitch 0.5mm of equivalent specifications, consider the process characteristic of rolling screw-threads processing, by to tooth form Strength co-mputation, to the Strength co-mputation of bolt minimum diameter (bottom of trench), scientific and reasonable test, accurate analog determination root of thread diameter, bottom of trench fillet radius, thread form angle, thread depth equidimension, the requirement of strength that should meet bolt meets the technological requirement of screw thread process again.
except screw thread ditch, the another weak part affecting the end bolt intensity particularly fatigue strength of bolt is the transition position in screw thread and bar portion, due to the sudden change in cross section, there is higher stress to concentrate, the for a change sudden change in cross section, screw-thread ending position devises the transition zone of about 20 ~ 40mm when designing, be progressively transitioned into diameter of thread, eliminate the abrupt change of cross-section by roll extrusion central diameter d, avoid the generation of stress concentration point, improve the working strength of bolt.Accompanying drawing 1 is seen at its shape and position
at the bottom of screw thread dental groove shape and tooth, the fatigue behaviour of fillet radius size to bolt also has a certain impact, when bolt bears stretching force, screw thread dental groove place will produce stress and concentrate, its value depends on the shape of dental groove to a great extent, the groove of bolt is more level and smooth, stress is concentrated less, and fatigue strength is higher.Design fillet radius size at the bottom of the corresponding tooth of the bolt design of different size during dental groove shape, make the groove of screw thread smooth-out, reduce stress and concentrate.
it will be recognized by those skilled in the art, under the prerequisite not departing from protection scope of the present invention, various amendment, change and combination can be carried out to above-mentioned mode of execution, and think that this amendment, change and combination are within the scope of originality thought.
Claims (4)
1. a tension control structure high-strength bolt, comprise screw rod and the screw thread being arranged on screw rod two ends, it is characterized in that, described screw thread has following specification:
When Major Diam is 30mm, the pitch of screw thread is 4.0mm, and thread form angle is 50 °, and screw thread height is 2.0mm, and lead angle is 2 ° 36 ', and fillet radius at the bottom of tooth is 0.6mm, and crest radius is 0.4mm, and screw-thread ending transition zone length is 24mm;
When Major Diam is 36mm, the pitch of screw thread is 4.5mm, and thread form angle is 50 °, and screw thread height is 2.2mm, and lead angle is 2 ° 24 ', and fillet radius at the bottom of tooth is 0.8mm, and crest radius is 0.6mm, and screw-thread ending transition zone length is 27mm;
When Major Diam is 42mm, the pitch of screw thread is 5.0mm, and thread form angle is 50 °, and screw thread height is 2.4mm, and lead angle is 2 ° 16 ', and fillet radius at the bottom of tooth is 1.0mm, and crest radius is 0.8mm, and screw-thread ending transition zone length is 30mm;
When Major Diam is 48mm, the pitch of screw thread is 5.5mm, and thread form angle is 50 °, and screw thread height is 2.6mm, and lead angle is 2 ° 13 ', and fillet radius at the bottom of tooth is 1.2mm, and crest radius is 1.0mm, and screw-thread ending transition zone length is 33mm;
When Major Diam is 56mm, the pitch of screw thread is 6.0mm, and thread form angle is 50 °, and screw thread height is 2.8mm, and lead angle is 2 ° 03 ', and fillet radius at the bottom of tooth is 1.4mm, and crest radius is 1.2mm, and screw-thread ending transition zone length is 36mm;
When Major Diam is 64mm, the pitch of screw thread is 6.5mm, and thread form angle is 50 °, and screw thread height is 3.0mm, and lead angle is 1 ° 58 ', and fillet radius at the bottom of tooth is 1.6mm, and crest radius is 1.4mm, and screw-thread ending transition zone length is 39mm;
Wherein, described screw-thread ending transition zone refers to and arranges transition zone at the transition position of screw thread and screw rod, and transition zone is progressively transitioned into diameter of thread by effective diameter of thread.
2. a kind of tension control structure high-strength bolt as claimed in claim 1, is characterized in that: make that P content in the alloy material of high-strength bolt should be less than 0.009%, s content should be less than 0.004%, and hydrogen content is less than 2mg/m
3, nitrogen content is less than 12mg/m
3, oxygen content 10mg/m
3, c content 0.25 ~ 0.30%, Si content 0.06 ~ 0.08%, Mn content 1.06 ~ 1.07%, Cr content 0.25 ~ 0.27%, Ti content 0.03%, B content is 0.002%.
3. a kind of tension control structure high-strength bolt as claimed in claim 1, is characterized in that adopting induction heating to carry out rapid thermal treatment to screw rod.
4. a kind of tension control structure high-strength bolt as claimed in claim 1, is characterized in that adopting roll forming techniques machining screw.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510436467.5A CN105065410A (en) | 2015-07-23 | 2015-07-23 | High-strength bolt for tension control structure |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510436467.5A CN105065410A (en) | 2015-07-23 | 2015-07-23 | High-strength bolt for tension control structure |
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| Publication Number | Publication Date |
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| CN105065410A true CN105065410A (en) | 2015-11-18 |
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|---|---|---|---|
| CN201510436467.5A Pending CN105065410A (en) | 2015-07-23 | 2015-07-23 | High-strength bolt for tension control structure |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108213864A (en) * | 2017-12-19 | 2018-06-29 | 深圳航空标准件有限公司 | The method and its bolt of bolt processing |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201074626Y (en) * | 2007-08-10 | 2008-06-18 | 南车资阳机车有限公司 | Check bolt |
| JP2013139872A (en) * | 2011-12-09 | 2013-07-18 | National Institute For Materials Science | High tensile bolt and method for manufacturing the same |
| CN203098519U (en) * | 2013-03-20 | 2013-07-31 | 浙江晋吉汽车配件有限公司 | Bolt with enlarging radius of rounded roof in thread ending position |
| CN203230707U (en) * | 2013-05-16 | 2013-10-09 | 湖北德克特种异型高强螺栓有限公司 | Fine-thread high-strength screw used for fan foundation |
| CN104033462A (en) * | 2014-06-10 | 2014-09-10 | 福建海源自动化机械股份有限公司 | Prestressed threaded pull rod device as well as production method and application thereof |
| CN104329346A (en) * | 2014-10-09 | 2015-02-04 | 青海金阳光特种钢材股份有限公司 | High-strength prestressed anchor bolt |
| CN204851925U (en) * | 2015-07-23 | 2015-12-09 | 南通汇能电力科技有限公司 | Tension control is high strength bolt for structure |
-
2015
- 2015-07-23 CN CN201510436467.5A patent/CN105065410A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201074626Y (en) * | 2007-08-10 | 2008-06-18 | 南车资阳机车有限公司 | Check bolt |
| JP2013139872A (en) * | 2011-12-09 | 2013-07-18 | National Institute For Materials Science | High tensile bolt and method for manufacturing the same |
| CN203098519U (en) * | 2013-03-20 | 2013-07-31 | 浙江晋吉汽车配件有限公司 | Bolt with enlarging radius of rounded roof in thread ending position |
| CN203230707U (en) * | 2013-05-16 | 2013-10-09 | 湖北德克特种异型高强螺栓有限公司 | Fine-thread high-strength screw used for fan foundation |
| CN104033462A (en) * | 2014-06-10 | 2014-09-10 | 福建海源自动化机械股份有限公司 | Prestressed threaded pull rod device as well as production method and application thereof |
| CN104329346A (en) * | 2014-10-09 | 2015-02-04 | 青海金阳光特种钢材股份有限公司 | High-strength prestressed anchor bolt |
| CN204851925U (en) * | 2015-07-23 | 2015-12-09 | 南通汇能电力科技有限公司 | Tension control is high strength bolt for structure |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108213864A (en) * | 2017-12-19 | 2018-06-29 | 深圳航空标准件有限公司 | The method and its bolt of bolt processing |
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