CN101501350A - High performance thread forming screw - Google Patents
High performance thread forming screw Download PDFInfo
- Publication number
- CN101501350A CN101501350A CNA2007800138679A CN200780013867A CN101501350A CN 101501350 A CN101501350 A CN 101501350A CN A2007800138679 A CNA2007800138679 A CN A2007800138679A CN 200780013867 A CN200780013867 A CN 200780013867A CN 101501350 A CN101501350 A CN 101501350A
- Authority
- CN
- China
- Prior art keywords
- screw
- self
- hardness
- tapping lock
- hrc
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Landscapes
- Heat Treatment Of Articles (AREA)
Abstract
The invention provides a thread forming screw and a method for forming the same. A thread forming screw having a minimum surface hardness of HRC 56. The screw can form threads in a workpiece having a surface hardness which exceeds HRC 23. A method of surface hardening a screw includes carbon enriching the screw to at least a 0.48% carbon level, and then quenching the screw. Then, the screw is tempered such that the surface hardness does not exceed the core hardness by more than 3 Rockwell C points, and both the surface and core are at a Rockwell C33-C39 hardness. Subsequently, the point is induction hardened, and the screw is quenched again. The screw is again tempered such that the lead threads and the first 3-4 full threads are at a Rockwell C56 minimum hardness, preferably to a depth of at least 0.008 inches, and the core of the fastener is at Rockwell C33-C39 hardness. Finally, a finish is applied.
Description
Technical field
The method that present invention relates in general to a kind of self-tapping lock screw and form described self-tapping lock screw, more specifically, relate to a kind of fastening piece, self-tapping lock screw for example, its at least a portion has the minimal surface hardness of HRC56 (RHC), and relates to a kind of method that forms this self-tapping lock screw.
Background technique
Now, proposing self-tapping lock screw in the industry can be that cold hobbing forms screw thread in C23 and the following workpiece at Rockwell hardness.The hardness of equally, present self-tapping lock screw is enough to form screw thread in this workpiece.Yet, also have and wish in some application that self-tapping lock screw can form screw thread above in the workpiece of HRC23 in hardness.For example, after forming High-Strength Low-Alloy (HSLA) material, for example by punching in material, near the hardness the hole can meet and exceed HRC 40.
The hardness of traditional self-tapping lock screw is not enough to successfully form screw thread above in the workpiece of HRC 23 by cold hobbing in hardness.For example, some self-tapping lock screws that can buy are treated to and make that the minimum hardness of the most advanced and sophisticated and junior three to four circle complete thread is a HRC 45, and the core hardness of fastening piece is a HRC 33 to 39.Cold hobbing forms screw thread to be not enough to surpass in the material of HRC23 continuously in hardness such as the hardness of the self-tapping lock screw of this screw.When this self-tapping lock screw being advanced to hardness is in HRC40 or the above HSLA material (or any other material) time, and subsiding appears in screw thread.Screw thread this subsides or is out of shape and make to connect and lost efficacy.When in such as the material of steel, forming screw thread, need make fastening piece have the material that will screw in and compare much higher hardness with fastening piece, can not subside correctly to form screw thread.
Because existing self-tapping lock screw is not enough to surpass cold hobbing formation screw thread in the workpiece of HRC23 in hardness, in the case, matching thread need be provided, for example by scyewed joint (needing boring and tapping operation) is provided in workpiece, perhaps, perhaps provide the similar approach of matching thread by providing like parts or use to be used to by welded nut, loose nut, solder-bump, screw thread embedded piece are provided.These structures/methods need extra operation, hardware and time, cause process cost higher, more consuming time.
Thereby, need on the market and can surpass the fastening piece that forms screw thread in the workpiece of HRC 23 (for example HSLA material or any other material) in hardness.
Summary of the invention
The purpose of embodiments of the invention provides a kind of self-tapping lock screw, and the surface hardness of its at least a portion is high enough to make this self-tapping lock screw to surpass cold hobbing formation screw thread in the workpiece of HRC23 in hardness.
Another purpose of embodiments of the invention provides a kind of self-tapping lock screw, and the surface hardness minimum of its at least a portion is HRC56.
An also purpose of embodiments of the invention provides a kind of self-tapping lock screw, and the minimal surface hardness of its at least a portion screw thread is HRC56, and the degree of depth is 0.02cm (0.008 inch) at least.
Briefly, according in the aforementioned purpose at least one, embodiments of the invention provide a kind of self-tapping lock screw, the threaded bar portion that it has head and extends from this head.At least a portion screw thread of this bar portion is through surface hardening, and preferably minimal surface hardness is HRC56, makes this self-tapping lock screw be used in surface hardness subsequently and surpasses cold hobbing formation screw thread in the workpiece of HRC23.
Another aspect of the present invention provides a kind of method that forms this self-tapping lock screw.This method comprises the execution heat treatment process, thereby makes this screw carburetting to carbon content at least 0.48%, and for example at oil quenching.Then, this screw tempering is to reduce fragility and to allow to have more ductile core.Preferably, tempering is controlled as and makes surface hardness be no more than 3 Rockwell hardness numbers of core hardness.Preferably, after tempering, the surface of this fastening piece and core hardness all are HRC 33 to 39.Subsequently, for example most advanced and sophisticated sensed sclerosis of three to four of helical pitch screw thread and this screw circle complete threads, and this screw for example quenches in water or in polymer solution quenchant.Then, this screw once more tempering to reduce fragility.Preferably, this tempering step is controlled as and for example makes that helical pitch screw thread and the junior three to four circle complete thread minimum hardness are HRC 56, preferably the degree of depth is at least 0.02cm (0.008 inch), and the core hardness of this fastening piece is a HRC 33 to 39.At last, preferably, to this fastening piece fine finishing.
Description of drawings
The tissue of structure of the present invention and operation and mode and other purpose thereof and advantage can be in conjunction with the drawings, understand better with reference to following explanation, the wherein similar similar element of reference character representative, wherein:
Fig. 1 be according to the embodiment of the invention can case-hardened a kind of screw side view;
Fig. 2 is the partial cross sectional view of the screw shown in Fig. 1; With
Fig. 3 is that the flow chart through the method for case-hardened self-tapping lock screw is made in explanation, and wherein this method is according to embodiments of the invention.
Embodiment
Although the present invention can be used for various forms of embodiments, illustrate in the drawings here and described a kind of embodiment in detail, should be appreciated that this specification is the example of principle of the present invention, rather than limit the present invention to scope described herein and that describe.
One aspect of the present invention relates to a kind of fastening piece, self-tapping lock screw for example, and the surface hardness of its at least a portion is HRC56.The method that relates to surface hardening fastening piece (for example self-tapping lock screw) on the other hand makes that the surface hardness of its at least a portion is HRC56.Although this method can be used for many screws, U.S. Patent No., 3935,785 disclose a kind of screw, and method can be used for this screw according to an embodiment of the invention, and introduces the full text of this patent by reference at this.
Shown in Fig. 1 and above-mentioned patent of the application, screw 10 comprises head 12 and 12 threaded bar portions 14 of extending from the head.End 16 places relative with head 12 near screw 10 have a plurality of helical pitch screw threads 18, and this helical pitch screw thread is somewhat tapered towards the tip 16 of screw 10.Between helical pitch screw thread 18 and head 12 a plurality of complete threads 20, wherein, reference character 22 expression first lap complete threads, reference character 24 expressions the 4th circle complete thread.About the shape of this concrete screw and the more details of function can find in above-mentioned patent.Yet, the example of preferred specific embodiment of the present invention as shown in Figure 2, wherein the helical pitch screw thread 18 and the junior three or four circle complete thread surface hardening are to Rockwell hardness HRC56 at least, and the degree of depth (be among Fig. 2 marked size 26) is at least 0.02cm (0.008 inch).Preferably, the core hardness of screw 10 is a HRC 33 to 39, makes screw 10 cores have ductile relatively core.As shown in Figure 2, reference character 28 represented parts have the minimum induction hardening zone of minimum Rockwell hardness C56, and reference character 30 represented parts have the maximum induction hardening zone of minimum Rockwell hardness C56 simultaneously.The part of reference character 32 expressions is sclerosis, quenching and tempering zone, and surface hardness departs from 3 Rockwell hardness numbers of core hardness.
Fig. 3 illustrates method according to an embodiment of the invention, and this method can be used for forming the self-tapping lock screw 10 shown in Fig. 1 and 2.This method provides the steel wire of for example being made by steel 4037 steel or similar alloy, and draws this steel wire on cold header.This material can be an alloyed steel, and AISI C4037 grade analysis, composition are carbon 0.35～0.40%; Manganese 0.70～0.90%; Sulphur maximum 0.040%; Phosphorus maximum 0.035%; Silicon 0.20～0.35% and molybdenum 0.20～0.30%, those skilled in the art are referred to as crystal grain thinning spheroidizing annealing steel usually.Certainly, other material also can use, and also integral body falls into scope of the present invention.In case cold-heading is finished, just on screw, form screw thread.These steps are conventional and known.
In case the formation screw is just carried out heat treatment process according to an embodiment of the invention.In heat treatment process, in quality furnace, use controlled method to make screw carburetting, make the Kohlenstoffgehalt of screw be at least 0.48%.Carburetting allows the surface hardening of fastening piece to being stiffer than body material.Particularly, screw can be placed in the stove 90 minutes, and furnace temperature is 1600～1700 Fahrenheits.The ring border preferably is controlled to be carbon potential 0.6%-0.7% (not having nitriding).Preferably, the degree of depth in carburetting zone (being the size 26 among Fig. 2) is at least 0.02cm (0.008 inch).Preferably, tempering rear surface hardness (under according to the core requirement chosen temperature) can not surpass core hardness more than 3 Rockwell hardness numbers (30 Vickers value).In selected furnace parameters, the surface hardness increase of 1 to 2 Rockwell hardness number (10～20 Vickers value) will be a purpose.Microhardness testers can be used for measuring the hardness and the degree of depth in carburetting zone, thereby help to set furnace parameters.
In case screw is through carburetting, screw just for example quenches in temperature is the oil of 140～160 Fahrenheits.After the quenching, for example tempering 90 minutes when temperature is 850～950 Fahrenheits of screw has more malleable core to reduce fragility and can form in fastening piece.Preferably, this step is controlled as and makes surface hardness can not surpass core hardness more than 3 Rockwell hardness numbers.At this moment, preferably, the surface of fastening piece and core hardness are HRC 33 to 39.
Subsequently, the sensed quenching in the tip of screw (for example helical pitch screw thread 18 and the junior three to four circle complete thread), thereby wherein the helical pitch screw thread of fastening piece instantaneous be subjected to effect of electric field with the screw thread induction heating to hardening temperature (about 1650～1750 Fahrenheits).This screw immediately quenches, for example water spray or polymer solution quenchant.
Subsequently, for example tempering at least 1 hour when 300 Fahrenheits of screw is to reduce fragility.The carburetting step of this tempering step and front is preferably effectively in conjunction with being HRC 56 so that the complete thread minimum hardness is enclosed in the helical pitch screw thread and the junior three to four, preferably the degree of depth is at least 0.02cm (0.008 inch), and the core hardness of fastening piece is a HRC 33 to 39.Although can use different tempering temperatures and endurance, temperature is preferably enough low to be HRC 56 to keep most advanced and sophisticated minimum hardness.At last, preferably, to fastening piece fine finishing.
One aspect of the present invention provides a kind of fastening piece, and the minimal surface hardness of its at least a portion is HRC56.For example, this fastening piece can be a U.S. Patent No. 3,935 for example, the self-tapping lock screw shown in 785, and wherein the minimal surface hardness of helical pitch screw thread and the junior three or four circle complete threads are HRC56.Like this, this screw is used in hardness and surpasses cold hobbing screw thread in the workpiece of HRC23, and this workpiece for example HSLA material or hardness is HRC40 or above any other material.
Another aspect of the present invention provides the method for at least a portion of a kind of surface hardening fastening piece, this fastening piece for example is a U.S. Patent No. 3,935, self-tapping lock screw shown in 785, make that the helical pitch screw thread of this screw and the minimal surface hardness of the junior three or four circle complete threads are HRC56, thereby this screw is used in hardness surpasses cold hobbing screw thread in the workpiece of HRC23, and this workpiece for example HSLA material or hardness is HRC40 or above any other material.
A kind of by-product, a kind of specifically the fastening piece of also providing on the one hand of the present invention by using said method to make.
Although illustrated and described a plurality of embodiment of the present invention, what should imagine is that those skilled in the art can design various deformation of the present invention without departing from the spirit and scope of the present invention.For example, although surface hardness described above can be hardened in helical pitch screw thread and the junior three or four circle screw threads, surface hardness can be hardened on screw thread more or less, and this all within the scope of the invention.In addition, although the HSLA material has been discussed in the explanation of front particularly, the present invention is used in except forming screw thread in the HSLA materials other.
Claims (19)
1, a kind of self-tapping lock screw, it is configured to surpass cold hobbing formation screw thread in the workpiece of HRC 23 in surface hardness, described self-tapping lock screw is characterised in that, the threaded bar portion that it has head and extends from this head, wherein, the surface hardness of at least a portion screw thread of described bar portion is at least HRC 56, thereby the workpiece cold hobbing that allows this self-tapping lock screw to be used for surpassing in surface hardness HRC 23 forms screw thread.
2, self-tapping lock screw as claimed in claim 1 is characterized in that, described threaded bar portion comprises the helical pitch screw thread at the place, end relative with described head near this screw.
3, self-tapping lock screw as claimed in claim 2 is characterized in that, described helical pitch screw thread is tapered towards the end of described screw.
4, self-tapping lock screw as claimed in claim 2, its feature also be, a plurality of complete threads in the described threaded bar portion are arranged between the head of described helical pitch screw thread and described screw.
5, self-tapping lock screw as claimed in claim 4 is characterized in that, the surface hardness of the described helical pitch screw thread of described screw and at least three circle complete threads is at least HRC 56, and the degree of depth is at least 0.02cm (0.008 inch).
6, self-tapping lock screw as claimed in claim 5 is characterized in that, the core hardness of described screw is positioned at the scope of HRC 33 to 39.
7, self-tapping lock screw as claimed in claim 6, it is characterized in that, the first portion of the described screw of the end of close described screw has the minimum induction hardening zone that minimum value is a HRC 56, and the second portion of described screw has the maximum induction hardening zone that minimum value is a HRC 56.
8, self-tapping lock screw as claimed in claim 7 is characterized in that, the surface hardness of the third part of described screw departs from 3 Rockwell hardness numbers of described core hardness.
9, a kind of method that forms self-tapping lock screw, this self-tapping lock screw are configured to surpass cold hobbing screw thread in the workpiece of HRC 23 in surface hardness, and described method is characterised in that, the steel wire that is formed from steel is provided; This steel wire of traction on cold header; On this steel wire, form screw thread to form screw; On described screw, carry out heat treatment operation, make this screw carburetting, and the helical pitch screw thread of the described screw of induction hardening and at least three circle complete threads, make the threaded bar portion that described self-tapping lock screw has head and extends from described head, and the surface hardness of at least a portion screw thread of described bar portion is at least HRC 56.
10, the method for formation self-tapping lock screw as claimed in claim 9, its feature also are, after making this screw carburetting and before the described helical pitch screw thread of the described screw of induction hardening and at least three circle complete threads, make this screw quench and tempering.
11, the method for formation self-tapping lock screw as claimed in claim 9, its feature also are, after the described helical pitch screw thread and at least three circle complete threads of the described screw of induction hardening, make this screw quench and tempering.
12, the method for formation self-tapping lock screw as claimed in claim 9, its feature also is, the step of described screw carburetting is comprised stopped this screw 90 minutes in stove, furnace temperature is 1600～1700 Fahrenheits, and the carbon potential of controlling this stove is 0.6～0.7%, wherein, the degree of depth in the carburetting zone of this screw is at least 0.02cm (0.008 inch).
13, the method for formation self-tapping lock screw as claimed in claim 9, its feature also is, after making this screw carburetting and before the described helical pitch screw thread of the described screw of induction hardening and at least three circle complete threads, make this screw quench and tempering, wherein, the step that makes this screw quench comprises and makes the oil quenching of this screw in 140～160 Fahrenheits.
14, the method for formation self-tapping lock screw as claimed in claim 9, its feature also is, after making this screw carburetting and before the described helical pitch screw thread of the described screw of induction hardening and at least three circle complete threads, make this screw quench and tempering, wherein, make the step of this screw tempering comprise to make the tempering 90 minutes when the temperature of 850～950 Fahrenheits of this screw, wherein, the surface hardness of described screw surpasses no more than 3 Rockwell hardness numbers of this core hardness, wherein, the surface of described screw and core hardness are HRC 33 to 39.
15, the method for formation self-tapping lock screw as claimed in claim 9, it is characterized in that, thereby the step of the described helical pitch screw thread of the described screw of described induction hardening and at least three circle complete threads comprises the instantaneous hardening temperature that is subjected to effect of electric field with described screw thread induction heating to 1650～1750 Fahrenheits of helical pitch screw thread of this screw.
16, the method of formation self-tapping lock screw as claimed in claim 9, its feature also is, after the described helical pitch screw thread and at least three circle complete threads of the described screw of induction hardening, this screw is quenched and tempering, wherein, described tempering step comprises makes the tempering at least one hour when 300 Fahrenheits of described screw, thereby reduce the fragility of this screw, wherein, described tempering step and carburetting step make that the minimum hardness of described helical pitch screw thread and at least junior three circle complete thread is a HRC 56, the degree of depth is at least 0.02cm (0.008 inch), and the core hardness of described fastening piece is a HRC 33 to 39.
17, the method for formation self-tapping lock screw as claimed in claim 9, its feature also is, after the described helical pitch screw thread and at least three circle complete threads of the described screw of induction hardening, make this screw quench and tempering, wherein, described tempering step and described carburetting step make that the minimum hardness of described helical pitch screw thread and at least junior three circle complete thread is a HRC 56, and the degree of depth is at least 0.02cm (0.008 inch), and the core hardness of described fastening piece is a HRC 33 to 39.
18, the method for formation self-tapping lock screw as claimed in claim 9, its feature are that also described steel wire comprises alloyed steel, press American Iron and Steel Institute C4037 grade analysis, and composition is a carbon 0.35～0.40%; Manganese 0.70～0.90%; Sulphur maximum 0.040%; Phosphorus maximum 0.035%; Silicon 0.20～0.35% and molybdenum 0.20～0.30%.
19, the method for formation self-tapping lock screw as claimed in claim 9 is characterized in that, makes the step of described screw carburetting comprise and makes described screw carburetting make the Kohlenstoffgehalt of described screw be at least 048%.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US74497406P | 2006-04-17 | 2006-04-17 | |
| US60/744,974 | 2006-04-17 | ||
| US11/695,341 | 2007-04-02 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN101501350A true CN101501350A (en) | 2009-08-05 |
Family
ID=40947381
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNA2007800138679A Pending CN101501350A (en) | 2006-04-17 | 2007-04-03 | High performance thread forming screw |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101501350A (en) |
Cited By (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104668414A (en) * | 2015-02-06 | 2015-06-03 | 舟山市7412工厂 | Forming method for locking thread |
| CN105008062A (en) * | 2013-02-26 | 2015-10-28 | 喜利得股份公司 | Method for producing a concrete screw |
| CN106402122A (en) * | 2016-10-27 | 2017-02-15 | 宁波长华长盛汽车零部件有限公司 | Gradient thread achieving automatic guide |
| CN107816483A (en) * | 2017-02-05 | 2018-03-20 | 超捷紧固系统(上海)股份有限公司 | Metric system self tapping backing-up screw and its manufacture method |
| CN108180206A (en) * | 2018-03-06 | 2018-06-19 | 江苏固德建筑机械有限公司 | A kind of hexagonal washer STAINLESS STEEL SELF DRILLING SCREWS and its preparation process |
| CN108180205A (en) * | 2018-03-06 | 2018-06-19 | 江苏固德建筑机械有限公司 | A kind of coiled hair cross STAINLESS STEEL SELF DRILLING SCREWS and its preparation process |
| CN108223534A (en) * | 2018-03-06 | 2018-06-29 | 江苏固德建筑机械有限公司 | A kind of round end washer cross Self Drilling Screws and its preparation process |
| CN108252999A (en) * | 2018-03-06 | 2018-07-06 | 江苏固德建筑机械有限公司 | A kind of coiled hair cross Self Drilling Screws and its preparation process |
| CN108252998A (en) * | 2018-03-06 | 2018-07-06 | 江苏固德建筑机械有限公司 | A kind of round end washer cross STAINLESS STEEL SELF DRILLING SCREWS and its preparation process |
| CN108278262A (en) * | 2018-03-06 | 2018-07-13 | 江苏固德建筑机械有限公司 | A kind of novel countersunk head cross Self Drilling Screws and its preparation process |
| CN108457957A (en) * | 2018-03-06 | 2018-08-28 | 江苏固德建筑机械有限公司 | A kind of countersunk head cross STAINLESS STEEL SELF DRILLING SCREWS and its preparation process |
| CN108488182A (en) * | 2018-03-06 | 2018-09-04 | 江苏固德建筑机械有限公司 | A kind of coiled hair cross Self Drilling Screws and its preparation process improving degree of being completely embedded |
| CN108561396A (en) * | 2018-03-06 | 2018-09-21 | 江苏固德建筑机械有限公司 | A kind of countersunk head cross Self Drilling Screws and its preparation process |
| CN108561395A (en) * | 2018-03-06 | 2018-09-21 | 江苏固德建筑机械有限公司 | A kind of novel round-head washer cross Self Drilling Screws and its preparation process |
| CN110983001A (en) * | 2019-12-27 | 2020-04-10 | 江苏南钢通恒特材科技有限公司 | 32CrB4 induction hardening and tempering process |
| CN111237312A (en) * | 2020-01-16 | 2020-06-05 | 芜湖强振汽车紧固件有限公司 | Self-locking bolt and manufacturing method thereof |
| CN112188874A (en) * | 2018-05-22 | 2021-01-05 | C·R·巴德股份有限公司 | System and method for sterile urine sampling |
| CN112522492A (en) * | 2020-10-28 | 2021-03-19 | 浙江自紧王机械有限公司 | Self-tightening nut and heat treatment process of self-tightening gasket |
| CN113814345A (en) * | 2021-09-18 | 2021-12-21 | 上海洋洋大多利五金制品有限公司 | Production process of self-tapping and self-drilling screw with strong fixing force |
-
2007
- 2007-04-03 CN CNA2007800138679A patent/CN101501350A/en active Pending
Cited By (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105008062A (en) * | 2013-02-26 | 2015-10-28 | 喜利得股份公司 | Method for producing a concrete screw |
| CN104668414A (en) * | 2015-02-06 | 2015-06-03 | 舟山市7412工厂 | Forming method for locking thread |
| CN106402122A (en) * | 2016-10-27 | 2017-02-15 | 宁波长华长盛汽车零部件有限公司 | Gradient thread achieving automatic guide |
| CN107816483A (en) * | 2017-02-05 | 2018-03-20 | 超捷紧固系统(上海)股份有限公司 | Metric system self tapping backing-up screw and its manufacture method |
| CN108252998A (en) * | 2018-03-06 | 2018-07-06 | 江苏固德建筑机械有限公司 | A kind of round end washer cross STAINLESS STEEL SELF DRILLING SCREWS and its preparation process |
| CN108488182A (en) * | 2018-03-06 | 2018-09-04 | 江苏固德建筑机械有限公司 | A kind of coiled hair cross Self Drilling Screws and its preparation process improving degree of being completely embedded |
| CN108223534A (en) * | 2018-03-06 | 2018-06-29 | 江苏固德建筑机械有限公司 | A kind of round end washer cross Self Drilling Screws and its preparation process |
| CN108252999A (en) * | 2018-03-06 | 2018-07-06 | 江苏固德建筑机械有限公司 | A kind of coiled hair cross Self Drilling Screws and its preparation process |
| CN108180206A (en) * | 2018-03-06 | 2018-06-19 | 江苏固德建筑机械有限公司 | A kind of hexagonal washer STAINLESS STEEL SELF DRILLING SCREWS and its preparation process |
| CN108278262A (en) * | 2018-03-06 | 2018-07-13 | 江苏固德建筑机械有限公司 | A kind of novel countersunk head cross Self Drilling Screws and its preparation process |
| CN108457957A (en) * | 2018-03-06 | 2018-08-28 | 江苏固德建筑机械有限公司 | A kind of countersunk head cross STAINLESS STEEL SELF DRILLING SCREWS and its preparation process |
| CN108180205A (en) * | 2018-03-06 | 2018-06-19 | 江苏固德建筑机械有限公司 | A kind of coiled hair cross STAINLESS STEEL SELF DRILLING SCREWS and its preparation process |
| CN108561396A (en) * | 2018-03-06 | 2018-09-21 | 江苏固德建筑机械有限公司 | A kind of countersunk head cross Self Drilling Screws and its preparation process |
| CN108561395A (en) * | 2018-03-06 | 2018-09-21 | 江苏固德建筑机械有限公司 | A kind of novel round-head washer cross Self Drilling Screws and its preparation process |
| CN112188874A (en) * | 2018-05-22 | 2021-01-05 | C·R·巴德股份有限公司 | System and method for sterile urine sampling |
| CN110983001A (en) * | 2019-12-27 | 2020-04-10 | 江苏南钢通恒特材科技有限公司 | 32CrB4 induction hardening and tempering process |
| CN111237312A (en) * | 2020-01-16 | 2020-06-05 | 芜湖强振汽车紧固件有限公司 | Self-locking bolt and manufacturing method thereof |
| CN112522492A (en) * | 2020-10-28 | 2021-03-19 | 浙江自紧王机械有限公司 | Self-tightening nut and heat treatment process of self-tightening gasket |
| CN113814345A (en) * | 2021-09-18 | 2021-12-21 | 上海洋洋大多利五金制品有限公司 | Production process of self-tapping and self-drilling screw with strong fixing force |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101501350A (en) | High performance thread forming screw | |
| JP5522548B2 (en) | Method for forming a high-performance screw forming screw | |
| JP2009533635A5 (en) | ||
| US6338600B2 (en) | Self-tapping, corrosion-resistant screw with hardened tip | |
| US20070062620A1 (en) | Fixing element comprising a low-alloyed steel and process for the production thereof | |
| CN107084181B (en) | Screw made of low-alloy carbon steel and method for manufacturing the same | |
| US6059898A (en) | Induction hardening of heat treated gear teeth | |
| US20210054866A1 (en) | Bimetallic screw with martensitically hardenable steel | |
| CN1274812A (en) | High-strength screw | |
| JP2020519757A (en) | Martensitic hardenable steel and its use, especially screw manufacturing | |
| DE102012216117A1 (en) | Method for producing a self-tapping screw | |
| JP4321974B2 (en) | Steel for high strength screws and high strength screws | |
| EP1371863B1 (en) | High-strength bolt excellent in delayed fracture resistance characteristics and its steel product | |
| JP4925971B2 (en) | Manufacturing method of tapping screws for high-tensile steel plate | |
| US5746845A (en) | Method for manufacturing high-strength member of precipitation hardening martensitic stainless steel | |
| US9267195B2 (en) | Tempered steel | |
| JPS62192531A (en) | Pin for clamp apparatus and its production | |
| JP4422924B2 (en) | Steel for high-strength tapping bolt, high-strength tapping bolt and method for producing high-strength tapping bolt | |
| US20150010376A1 (en) | Bolt-like fastening element, in particular drilling screw, and connection established thereby | |
| WO2024127490A1 (en) | Pc steel rod and high-strength bolt having excellent delayed fracture resistance and having structure for preventing falling-out of screw, and method for producing same | |
| TWI816092B (en) | Method for manufacturing a screw, and screw | |
| US20060169374A1 (en) | Process for the production of an articulated structural part having improved wear resistance | |
| DE69525276T2 (en) | Threaded fastener made of alloy steel with high fatigue resistance and its manufacturing process | |
| DE102008050319A1 (en) | Method of case-hardening steel gear wheels or other components used in e.g. automobile industry, work-hardens before carburization and heat treatment |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Open date: 20090805 |