CN103674389B - Test method of determining catheter sealing joint tightening torque - Google Patents
Test method of determining catheter sealing joint tightening torque Download PDFInfo
- Publication number
- CN103674389B CN103674389B CN201310576887.4A CN201310576887A CN103674389B CN 103674389 B CN103674389 B CN 103674389B CN 201310576887 A CN201310576887 A CN 201310576887A CN 103674389 B CN103674389 B CN 103674389B
- Authority
- CN
- China
- Prior art keywords
- torque value
- screw
- down torque
- minimum
- tightening torque
- 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.)
- Active
Links
Landscapes
- Examining Or Testing Airtightness (AREA)
Abstract
The invention discloses a test method of determining a catheter sealing joint tightening torque. A minimum pre-tightening force and a maximum pre-tightening force are used to calculate a theoretical minimum tightening torque value and a theoretical maximum tightening torque value of the catheter sealing joint; while the theoretical minimum tightening torque value serves as a starting point, a tightening torque value gradually increases at a certain interval, and an air tightness test of the catheter sealing joint is carried out at each tightening torque value, so that a test minimum tightening torque value meeting a leakage ratio is obtained; the test minimum tightening torque value meeting the leakage ratio is multiplied by a torque attenuation coefficient so as to obtain a final tightening torque value; and based on the tightening torque which is obtained when the final tightening torque value is multiplied by 1.25, the catheter sealing joint is tightened, and a thread strength is determined whether thread strength meets requirements. If the thread strength does not meet the requirements, the catheter sealing joint structure is re-designed, and the final tightening torque value is determined; and if the thread strength meets the requirements, then the test comes to an end.
Description
Technical field
The present invention relates to a kind of test method determining conduit sealing adaptor screw-down torque.
Background technology
As shown in Figure 1, the step conduit sealing adaptor that certain carrier rocket newly grinds comprises concave station rank joint 1, boss rank joint 2, metallic gasket 3 and cap nut 4, its sealing principle relies on the pressure produced that is threaded to make metallic gasket generation yield deformation, realize the filling in microcosmic gap between joint face, thus ensure sealing.By special tightening tool (i.e. torque spanner) fastening nut, screw-down torque value can be shown in real time in rundown process.For this kind of conduit sealing adaptor, require to be not higher than 1 × 10 according to leak rate
-5pa.m
3the condition of/s, has carried out the research work that moment quantizes, has defined a set of test method rationally determining conduit sealing adaptor screw-down torque.
Summary of the invention
The object of the present invention is to provide a kind of test method determining conduit sealing adaptor screw-down torque, the request for utilization under the various operating mode of conduit sealing adaptor be threaded with satisfied dependence, particularly closes in seal request high field.
The present invention includes following technical scheme:
Determine a test method for conduit sealing adaptor screw-down torque, described conduit sealing adaptor comprises metallic gasket and nut, comprises the steps:
(1) theory minimum screw-down torque value and the maximum screw-down torque value of theory of conduit sealing adaptor is calculated according to minimum pretightning force and maximum pretightning force;
(2) using minimum for described theory screw-down torque value as starting point, increase screw-down torque value gradually at certain intervals, under each screw-down torque value, airtight detection carried out to described conduit sealing adaptor, draw the minimum screw-down torque value of the test meeting leak rate requirement;
(3) the described minimum moment values of test meeting leak rate requirement is multiplied by moment attenuation coefficient and draws final screw-down torque value;
(4) moment final screw-down torque being multiplied by 1.25 acquisitions tightens described conduit sealing adaptor, determines whether screw strength meets the demands;
If screw strength does not meet the demands, bamboo product need be carried out to conduit seal joint structure, and return step (1);
If screw strength meets the demands, then terminate.
Described minimum pretightning force is determined by the seal pressure of metallic gasket.
Described moment attenuation coefficient is 1.25 ~ 1.3.
The present invention compared with prior art tool has the following advantages:
In test method of the present invention using minimum for theory screw-down torque value as starting point, increase screw-down torque value gradually at certain intervals, under each screw-down torque value, airtight detection is carried out to described conduit sealing adaptor, draw the minimum screw-down torque value of the test meeting leak rate requirement; The described minimum moment values of test meeting leak rate requirement is multiplied by moment attenuation coefficient and draws final screw-down torque value.The determined final screw-down torque value of the present invention can realize joint leak rate lower than 10
-7pa.m
3the use of/s magnitude, far above its designing requirement, has certain reliability.
Accompanying drawing explanation
Fig. 1 is the structural representation of conduit sealing adaptor;
Fig. 2 is the process flow diagram of the test method determining conduit sealing adaptor screw-down torque.
Embodiment
Just by reference to the accompanying drawings the present invention is described further below.
As shown in Figure 1, to be realized the steps type seal joint of sealing by compressed metal packing ring, determine that the test method step of screw-down torque is as follows:
1, according to the relational expression of pretightning force and screw-down torque, the theory minimum screw-down torque value of sealing and maximum screw-down torque value is met.
The relational expression of pretightning force and screw-down torque is as follows:
wherein M: screw-down torque, N.m; Q: pretightning force, N; Dc: the central diameter of screw thread, mm; β: flank angle 30 °; P: pitch, mm; r
f: rubbing surface mean radius, mm; μ: friction factor.
Wherein minimum pretightning force is determined (namely the minimum seal pressure of metallic gasket is multiplied by compression area) by the seal pressure of metallic gasket, and maximum pretightning force is determined according to the yield stress of thread material.The yield stress of described thread material comprises screw thread shear stress τ, bending stress σ
w.According to screw thread shear stress τ, bending stress σ
wbe respectively with the relational expression of pretightning force:
with
determine the pretightning force that shear stress is corresponding, the pretightning force that bending stress is corresponding respectively, using a pretightning force minimum in these two pretightning forces as described maximum pretightning force.Wherein, Q: pretightning force, N; F
j: single pitch thread shear(ing) area, F
j=0.875 π dP, mm
2; X
l: the screw thread arm of force, X
l=0.325P, mm; W: single pitch thread section factor, W=0.128 π dP
2, mm
3; N: thread turns; D: screw thread nominal diameter, mm; P: pitch, mm.
2, determine to test minimum screw-down torque value M by test
0, namely with the minimum screw-down torque of theory for starting point tightens joint, carry out the airtight detection of normal temperature, if leak rate does not meet the demands, then with certain moment interval multistage loadings, until leak rate meets the demands, corresponding moment values is M
0.Notice that moment loads and should not exceed theoretical maximum screw-down torque value.Moment interval is generally rule of thumb determined, if latus rectum specification is the pipe joint element of 4mm, and the desirable 3N.m in moment interval.The airtight test example of normal temperature is as used helium Mass Spectrometry detection method.
3, the minimum screw-down torque value M determined is being tested
0on basis, be multiplied by moment attenuation coefficient, obtain final screw-down torque value M.Described moment attenuation coefficient is 1.25 ~ 1.3.
4, with 1.25 times of final screw-down torque value M, examination screw strength;
If screw strength does not meet the demands (namely occurring thread biting locking or screw thread damage), then need to carry out bamboo product (such as changing thread material coupling etc.) to conduit seal joint structure, and redefine final screw-down torque value according to above-mentioned steps, if screw strength meets the demands (namely not occurring thread biting locking or screw thread damage), then terminate.
The unspecified part of the present invention belongs to general knowledge as well known to those skilled in the art.
Claims (3)
1. determine a test method for conduit sealing adaptor screw-down torque, described conduit sealing adaptor comprises metallic gasket and nut, it is characterized in that, described test method comprises the steps:
(1) theory minimum screw-down torque value and the maximum screw-down torque value of theory of conduit sealing adaptor is calculated according to minimum pretightning force and maximum pretightning force;
(2) using minimum for described theory screw-down torque value as starting point, increase screw-down torque value gradually at certain intervals, under each screw-down torque value, airtight detection is carried out to described conduit sealing adaptor, draw the minimum screw-down torque value of the test meeting leak rate requirement;
(3) the described test minimum screw-down torque value meeting leak rate requirement is multiplied by moment attenuation coefficient and draws final screw-down torque value;
(4) moment that final screw-down torque value is multiplied by 1.25 acquisitions is tightened described conduit sealing adaptor, determine whether screw strength meets the demands;
If screw strength does not meet the demands, bamboo product need be carried out to conduit seal joint structure, and return step (1);
If screw strength meets the demands, then terminate.
2. the method for claim 1, is characterized in that: described minimum pretightning force is determined by the seal pressure of metallic gasket.
3. the method for claim 1, is characterized in that: described moment attenuation coefficient is 1.25 ~ 1.3.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310576887.4A CN103674389B (en) | 2013-11-18 | 2013-11-18 | Test method of determining catheter sealing joint tightening torque |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310576887.4A CN103674389B (en) | 2013-11-18 | 2013-11-18 | Test method of determining catheter sealing joint tightening torque |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN103674389A CN103674389A (en) | 2014-03-26 |
| CN103674389B true CN103674389B (en) | 2015-07-15 |
Family
ID=50312629
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201310576887.4A Active CN103674389B (en) | 2013-11-18 | 2013-11-18 | Test method of determining catheter sealing joint tightening torque |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103674389B (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106404245B (en) * | 2016-08-24 | 2019-04-16 | 北京星航机电装备有限公司 | A kind of flared type combined catheter cap nut mounting torque determines method |
| CN106931931B (en) * | 2017-03-29 | 2018-09-28 | 王洸泽 | A kind of flexible plough groove type pipe joint deflection angle automatic testing equipment of fire-fighting |
| CN106950109B (en) * | 2017-04-01 | 2023-08-08 | 山东省产品质量检验研究院 | Automatic test device for bearing moment of groove type pipe joint for fire control |
| CN107538211B (en) * | 2017-09-30 | 2019-02-19 | 安徽江淮汽车集团股份有限公司 | A kind of determination method of the urgent torque of suspension system attachment bolt |
| CN109397170B (en) * | 2018-11-23 | 2020-11-13 | 中国航发北京航科发动机控制系统科技有限公司 | Method for verifying effective tightening torque of lock nut |
| CN111062101B (en) * | 2019-12-18 | 2023-03-28 | 西安航天动力研究所 | Method for determining tightening torque of threaded connection of pipeline |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201876333U (en) * | 2010-12-02 | 2011-06-22 | 核动力运行研究所 | Torque testing device of valve electric actuating mechanism |
| CN102519652A (en) * | 2011-12-16 | 2012-06-27 | 天津大学 | Bolt pre-tightening force testing device and control method thereof |
| CN103149023A (en) * | 2013-03-18 | 2013-06-12 | 深圳市瑞格尔仪器有限公司 | Nut performance testing device and nut performance testing machine |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0354430A (en) * | 1989-07-24 | 1991-03-08 | Kawasaki Steel Corp | Method for tightening coupling of oil well pipe and method for judging abnormality in tightening |
| WO2001086185A1 (en) * | 2000-05-10 | 2001-11-15 | Sumitomo Metal Industries, Ltd. | Method of tightening pipe joint |
-
2013
- 2013-11-18 CN CN201310576887.4A patent/CN103674389B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201876333U (en) * | 2010-12-02 | 2011-06-22 | 核动力运行研究所 | Torque testing device of valve electric actuating mechanism |
| CN102519652A (en) * | 2011-12-16 | 2012-06-27 | 天津大学 | Bolt pre-tightening force testing device and control method thereof |
| CN103149023A (en) * | 2013-03-18 | 2013-06-12 | 深圳市瑞格尔仪器有限公司 | Nut performance testing device and nut performance testing machine |
Non-Patent Citations (1)
| Title |
|---|
| 螺纹结构力矩及其衰退机理分析;殷明霞等;《强度与环境》;20130831;第40卷(第4期);31－35 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN103674389A (en) | 2014-03-26 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103674389B (en) | Test method of determining catheter sealing joint tightening torque | |
| EP3126096B1 (en) | Interface device for tensioning a nut and a bolt assembly | |
| EP3708892B1 (en) | Threaded connection for steel pipe | |
| US3139294A (en) | Flared tube fitting | |
| US7017951B2 (en) | Strengthened pipe fitting having encapsulated reenforcing collar | |
| CN203585616U (en) | Son and mother sealing ring for connecting smooth metal pipes | |
| CN111062101B (en) | Method for determining tightening torque of threaded connection of pipeline | |
| CN204785169U (en) | Pipeline connecting structure | |
| CN110985783A (en) | Flexible graphite metal corrugated tooth composite gasket sealing structure | |
| CN105134673B (en) | The super-pressure conical surface is sealed from pretension accumulator firmly | |
| CN207349426U (en) | A kind of piston with durable seal circle | |
| CN203297798U (en) | High pressure delivery pipeline pipe end connector structure | |
| CN206468939U (en) | The Hermetical connecting structure of thin walled hard metal circular tube | |
| CN112628519B (en) | High-pressure self-tightening type pipeline plug and application thereof | |
| CN203035112U (en) | Novel structural oil pipeline for oil and gas well | |
| CN106404245B (en) | A kind of flared type combined catheter cap nut mounting torque determines method | |
| CN205824430U (en) | A kind of vacuum pipe retractor device of adjustable sealing specific pressure | |
| CN214579456U (en) | Pipeline sealing structure suitable for less oil equipment | |
| CN104075059A (en) | Expansion joint self-balance type structure | |
| CN210375510U (en) | Pressure gauge joint | |
| CN202901598U (en) | Hydraulic pneumatic pipe connector | |
| CN218914039U (en) | Low-pressure fluid conveying pipe connecting piece | |
| Dong et al. | The Design and Mechanical Study of the Pipe Joint Structure in a High-pressure Hydraulic System | |
| CN220870303U (en) | Water pump pipe connecting device | |
| CN211667299U (en) | Connecting device of compressed air pulse valve and dust remover box |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |