When God nine perfect docking with Temple the moment , Shanghai Academy of Spaceflight Technology 805 reports cheering sound into a hall as a docking mechanism for research and development unit , every face was beaming with pride smile. 33 -year-old Geng Haifeng , deputy director of the docking mechanism is the designer , he told reporters about God nine docking with Temple was " seamless" secret --- seals.
"When Shenzhou nine successful docking with Temple One , luggage seals the channel is opened, the two connecting body will form a large airlock order to ensure the safety of the astronauts in the cabin , the entire capsule tightness is essential. How guarantee complete sealing ring is one of the key points . " Geng Haifeng said.
Ring was placed in the Shenzhou nine active docking groove in the surface structure of the butt . Common with people living in different O-ring , God seals on nine docking mechanism was T-type, was stuck in a groove , no force in the case of space , does not automatically fall off.
Before docking with Temple One , God of nine docking mechanism mounted on the seal on the " bare ." In the harsh environment of space , seals to withstand 100 degrees Celsius to minus 75 degrees Celsius high temperature test , but also to withstand a variety of space radiation ,security stickers which for the production of seals general materials, " Silastic " , it is almost impossible, because silicone rubber in a low temperature environment of " embrittlement " feature.
In order to study the special anti- brittle ring material , Geng Haifeng led the research team from the beginning of 2002 , before and after a six-year science and technology research . 2008 After the successful development of a single product , but also the whole together with a variety of validation tests and overcome countless difficulties
high security bolt seals
high security bolt seals
2013年9月13日星期五
2013年9月11日星期三
Detailed knowledge of the mechanical seal corrosion protection
The mechanical seal special structural form and the working environment and conditions, corrosion damage morphology are also diverse . PTFE seals, PTFE gasket seals and other mechanical damage to the main form of common corrosion damage , thermal damage and mechanical damage. Where corrosion damage greater harm .
A metal ring corrosion
1 , uniform surface corrosion. If the metal ring surface contact with corrosive media , and the metal itself impatience corrosion , it will produce surface corrosion , and its phenomena are leaks, early wear and tear , damage, sound and so on. Uniform corrosion of metal surfaces and non- film forming two forms , free film very dangerous metal corrosion , stress corrosion cracking is called , the choice of surfacing alloy and cast iron , tungsten carbide, titanium carbide seal ring , prone to stress corrosion rupture. Etching process with a constant speed , so that galvanic corrosion intensified.
2 , stress corrosion cracking. Metal corrosion and tensile stress at the same time under the effect of wear resistance. Corrosion fill F4 ring filled mainly refers selective etching , stripping damage or deterioration . If the hydrofluoric acid , the glass fiber molecule hot corrosion , these cracks communicate the seal faces , accelerated wear of the end face , an increase of leakage .
Two non-metallic corrosion ring
1 , graphite ring corrosion. Enterprise Information Network mentioned impregnated with resin impervious graphite ring , its corrosion for three reasons: First, when the face overheating when the temperature is higher than 180oC , to break away from the resin impregnated graphite ring , the ring wear down ; Second, if the resin impregnated inappropriate choice , so cable security seals cooling system establishment , which is mainly caused by the mistakes selection . The corrosion film , the passivation film characteristics generally has a protective effect , but the metal material used for the sealing ring , such as stainless steel , cobalt -chromium alloy such as a passivation film on the surface friction of the end face destruction , under hypoxic conditions New film is difficult to generate , select corrosion resistant impregnating resin , the use of high pressure impregnation , impregnation depth increase is necessary .
2 , the oxidation of the graphite ring . In an oxidizing medium, the end face or poor cooling in the dry friction generated when a temperature of 350 ~ 40o ℃ graphite ring can react with oxygen to produce CO, gas , can face becomes rough, or even rupture. Metallic ring , while chemical medium and under stress , will rupture.
3 , polytetrafluoroethylene ( PTFE gasket ) corrosion of the sealing ring . Will undergo chemical changes in the medium , but also the wear resistance decreased ; third resin impregnated deep enough, when rubbed impregnation layer , abrasion resistance decreases. F4 filler such as glass fiber , the first crack in the weakened area , and then to develop in depth , to rupture , crack trailer seals sealing ring generally radially diverging type, can be one or more . Graphite , metal powder to improve its heat resistance , wear resistance. Corrosion fill F4 ring filled mainly refers selective etching , stripping damage or deterioration . Such as hydrofluoric acid , hot corrosion of glass fiber molecules , so what things should be filled , as the case may be.
A metal ring corrosion
1 , uniform surface corrosion. If the metal ring surface contact with corrosive media , and the metal itself impatience corrosion , it will produce surface corrosion , and its phenomena are leaks, early wear and tear , damage, sound and so on. Uniform corrosion of metal surfaces and non- film forming two forms , free film very dangerous metal corrosion , stress corrosion cracking is called , the choice of surfacing alloy and cast iron , tungsten carbide, titanium carbide seal ring , prone to stress corrosion rupture. Etching process with a constant speed , so that galvanic corrosion intensified.
2 , stress corrosion cracking. Metal corrosion and tensile stress at the same time under the effect of wear resistance. Corrosion fill F4 ring filled mainly refers selective etching , stripping damage or deterioration . If the hydrofluoric acid , the glass fiber molecule hot corrosion , these cracks communicate the seal faces , accelerated wear of the end face , an increase of leakage .
Two non-metallic corrosion ring
1 , graphite ring corrosion. Enterprise Information Network mentioned impregnated with resin impervious graphite ring , its corrosion for three reasons: First, when the face overheating when the temperature is higher than 180oC , to break away from the resin impregnated graphite ring , the ring wear down ; Second, if the resin impregnated inappropriate choice , so cable security seals cooling system establishment , which is mainly caused by the mistakes selection . The corrosion film , the passivation film characteristics generally has a protective effect , but the metal material used for the sealing ring , such as stainless steel , cobalt -chromium alloy such as a passivation film on the surface friction of the end face destruction , under hypoxic conditions New film is difficult to generate , select corrosion resistant impregnating resin , the use of high pressure impregnation , impregnation depth increase is necessary .
2 , the oxidation of the graphite ring . In an oxidizing medium, the end face or poor cooling in the dry friction generated when a temperature of 350 ~ 40o ℃ graphite ring can react with oxygen to produce CO, gas , can face becomes rough, or even rupture. Metallic ring , while chemical medium and under stress , will rupture.
3 , polytetrafluoroethylene ( PTFE gasket ) corrosion of the sealing ring . Will undergo chemical changes in the medium , but also the wear resistance decreased ; third resin impregnated deep enough, when rubbed impregnation layer , abrasion resistance decreases. F4 filler such as glass fiber , the first crack in the weakened area , and then to develop in depth , to rupture , crack trailer seals sealing ring generally radially diverging type, can be one or more . Graphite , metal powder to improve its heat resistance , wear resistance. Corrosion fill F4 ring filled mainly refers selective etching , stripping damage or deterioration . Such as hydrofluoric acid , hot corrosion of glass fiber molecules , so what things should be filled , as the case may be.
Can I use car lights Mifengbuyan warm baked
A: This time is often heavy rain phenomenon , it finished the rain , my car 's headlights is a fine mist of water inside ; think of the car when a mist , use baking way to remove warm air ,truck seal I do not know whether it also applies to headlights do ?
Q: As lights Mifengbuyan in cleaning and when it rains is likely to cause the water , and when large temperature difference between inside and outside , when it will form a mist. This time is best not to carry high temperature baking, headlight plastic materials are generally qualitative , if the baking temperature is too high , it may cause the headlights look in softening deformation , affecting the use and appearance. In addition , the lights are generally monolithic , transparent lamp , the lamp will stick with a protective body back , between the two will result in high-temperature baking gum melt adhesive , increasing the vehicle lights the possibility of water . In general, the moisture inside the headlights in the daytime sunlight can quickly evaporate . If your headlights frequent water phenomenon,security seal labels it should go to the service station to check the lamp body , to see is not due to damage caused by the collision lights , resulting in frequent water.
Q: As lights Mifengbuyan in cleaning and when it rains is likely to cause the water , and when large temperature difference between inside and outside , when it will form a mist. This time is best not to carry high temperature baking, headlight plastic materials are generally qualitative , if the baking temperature is too high , it may cause the headlights look in softening deformation , affecting the use and appearance. In addition , the lights are generally monolithic , transparent lamp , the lamp will stick with a protective body back , between the two will result in high-temperature baking gum melt adhesive , increasing the vehicle lights the possibility of water . In general, the moisture inside the headlights in the daytime sunlight can quickly evaporate . If your headlights frequent water phenomenon,security seal labels it should go to the service station to check the lamp body , to see is not due to damage caused by the collision lights , resulting in frequent water.
Car sealing strip composition and application
There is a very important car body sealing member is made of a synthetic rubber seal, also known as protective molding gibs . Mainly used in door frames, side windows , front and rear windshield , hood and trunk lid , make the seal , the other also played vibration protection.
Production of sealing material is mainly polyvinyl chloride (PVC), ethylene propylene rubber (EPDM), synthetic rubber-modified polypropylene (PP-EPDM) , etc., by extrusion molding or injection molding method is made.
Compartment door seal mainly refers to the door frame and the door seal head and said seal. Door seal by definition is mounted on the door frame seal. Door seal not only to ensure tightness , but also bear the impact force when closed , hence it must be flexible , but also toughness , mainly by the dense gel matrix and sponge rubber foam tube composed of two parts . Dense gel containing metal skeleton, serve to strengthen the stereotypical strip and fixation. Sponge rubber foam tube is soft and elastic , plays compression deformation, pressure relief bounce function. In addition, some seal lip portion constituted by the color or affixed with glue fabric , color and beautiful decorative effect.
Door head and said seal structure , there are two , one for the whole sponge rubber foam tube , and another by a dense rubber and sponge rubber matrix composition . This seal glue or embedded in the door, and the door seal with , in order to increase the door and the body of the seal. Door seal head and said not every car are used , such as some economy cars would not , mainly from cost savings considerations.
Bonnet sealing strip made of pure foam sponge rubber sponge rubber foam tube or pipe and compacting plastic composite structure for the engine cover with the front section of the seal. Trunk lid or rear door seal by a dense skeleton containing gum base and sponge rubber foam tubes that can withstand a certain impact, ensure that the back cover is closed seal.
There are front and rear window seal of windshield seals, glass run channel and window seals inside and outside bar .
Front and rear windshield seal surrounded by the pure gum type of connection is made , it also has considerable flexibility hardness, in between the windshield and the body play mat care, fixation and seal. Glass run channel seal by a different hardness dense rubber composition with inlaid into the body to ensure the accuracy of dimensions , to cable seals against leakage , noise effect. The lip seal is also flocked surface is attached , when the glass moves up and down the glass can be reduced and the sliding friction between the strips , but also can reduce the noise. This form is also used for sealing sunroof seal. Inside and outside the window type of glue made from the pure or pure plastic and plastic composite type of structure, it comes with flocking surface , in addition to reducing the friction with the glass , but also play a decorative role .
Since the doors , hood and more complex geometry of the window , in the corner where the shape is often compared to adopt special seal. Therefore, there are car seal inscribed angle connector type and a variable cross-section type and other special seal, conventional sealing strip with a special seal both ends connected by molding processing or single-ended and then meet at the corner parts of the overall seal and parts of the installation requires special shape .
Past security seals produced using artificial compression molding , process simple backward , shape a single , mostly H-shaped . The seal is now under the control produced using extrusion molding machine or injection molding techniques , including the composite extrusion , variable diameter extrusion, microwave curing , the surface coating technology. For example , under the control of the computer , the variable diameter seal extrusion technology in the extrusion process can change the size and shape of the cross-section shape varied , go. Thus, the seal can be close to the body , good sealing effect .
Production of sealing material is mainly polyvinyl chloride (PVC), ethylene propylene rubber (EPDM), synthetic rubber-modified polypropylene (PP-EPDM) , etc., by extrusion molding or injection molding method is made.
Compartment door seal mainly refers to the door frame and the door seal head and said seal. Door seal by definition is mounted on the door frame seal. Door seal not only to ensure tightness , but also bear the impact force when closed , hence it must be flexible , but also toughness , mainly by the dense gel matrix and sponge rubber foam tube composed of two parts . Dense gel containing metal skeleton, serve to strengthen the stereotypical strip and fixation. Sponge rubber foam tube is soft and elastic , plays compression deformation, pressure relief bounce function. In addition, some seal lip portion constituted by the color or affixed with glue fabric , color and beautiful decorative effect.
Door head and said seal structure , there are two , one for the whole sponge rubber foam tube , and another by a dense rubber and sponge rubber matrix composition . This seal glue or embedded in the door, and the door seal with , in order to increase the door and the body of the seal. Door seal head and said not every car are used , such as some economy cars would not , mainly from cost savings considerations.
Bonnet sealing strip made of pure foam sponge rubber sponge rubber foam tube or pipe and compacting plastic composite structure for the engine cover with the front section of the seal. Trunk lid or rear door seal by a dense skeleton containing gum base and sponge rubber foam tubes that can withstand a certain impact, ensure that the back cover is closed seal.
There are front and rear window seal of windshield seals, glass run channel and window seals inside and outside bar .
Front and rear windshield seal surrounded by the pure gum type of connection is made , it also has considerable flexibility hardness, in between the windshield and the body play mat care, fixation and seal. Glass run channel seal by a different hardness dense rubber composition with inlaid into the body to ensure the accuracy of dimensions , to cable seals against leakage , noise effect. The lip seal is also flocked surface is attached , when the glass moves up and down the glass can be reduced and the sliding friction between the strips , but also can reduce the noise. This form is also used for sealing sunroof seal. Inside and outside the window type of glue made from the pure or pure plastic and plastic composite type of structure, it comes with flocking surface , in addition to reducing the friction with the glass , but also play a decorative role .
Since the doors , hood and more complex geometry of the window , in the corner where the shape is often compared to adopt special seal. Therefore, there are car seal inscribed angle connector type and a variable cross-section type and other special seal, conventional sealing strip with a special seal both ends connected by molding processing or single-ended and then meet at the corner parts of the overall seal and parts of the installation requires special shape .
Past security seals produced using artificial compression molding , process simple backward , shape a single , mostly H-shaped . The seal is now under the control produced using extrusion molding machine or injection molding techniques , including the composite extrusion , variable diameter extrusion, microwave curing , the surface coating technology. For example , under the control of the computer , the variable diameter seal extrusion technology in the extrusion process can change the size and shape of the cross-section shape varied , go. Thus, the seal can be close to the body , good sealing effect .
Liquid sealant effect it has five broad areas of application
Sealant is a primer with the shape of the sealing surface deformation, not flowing, there is a certain adhesion of the sealing material. Configuration is used to fill the gap , in order to play the role of the adhesive seal . Typically bituminous , natural resins or synthetic resins such as natural rubber or synthetic rubber or dry dry viscous material as the base material , with talc , clay , carbon black, titanium dioxide and inert fillers such as asbestos , then add plasticizers, solvents , curing agent and catalyst is made. Sealant has good sealing performance , and good heat resistance, pressure resistance, dense medium characteristics, use of simple , commonly used in mechanical and electrical products still seal between joints , as well as more complex threaded joints sealing , etc. , sealants, liquid sealant is generally divided into two categories with anaerobic ,security seals and more commonly used liquid sealant role has the following five effects:
1 , the surface effect
No matter how solid gasket compression , it will not completely fill the joints on uneven, there will always be a gap at the interface , and the liquid sealant was able to fill all depressions , showing a good sealing effect.
2 , adhesion results
Liquid sealant in liquid form , has a certain viscosity , having a joining surface of the metal adhesion , sealing beneficial .
3 , the thin film effect
In the joints between the liquid sealant is screw fastening , the formation of a film with the same space at the same time is very consistent with the surface . Meanwhile , the thinner the film , the greater resilience , the better seal.
4 , flow and pressure resistance
Using liquid metal sealant joints , gaps are generally less than 0.1mm , and the liquid sealant is a liquid of high viscosity , it is difficult to flow , thereby maintaining its good sealing .
5, the volume change and mobility
Solid gasket leak-proof effect is the compression of the cushion sheet elastic deformation . The liquid sealant is leakproof volume in the compression and stretching deformation , it does not exist solid gasket compression deformation, so there is no compression fatigue , pull tight seals elastic failure , stress relaxation and other phenomena , and it is always connected adhesion of the interface , the interface can be prevented leakage .
1 , the surface effect
No matter how solid gasket compression , it will not completely fill the joints on uneven, there will always be a gap at the interface , and the liquid sealant was able to fill all depressions , showing a good sealing effect.
2 , adhesion results
Liquid sealant in liquid form , has a certain viscosity , having a joining surface of the metal adhesion , sealing beneficial .
3 , the thin film effect
In the joints between the liquid sealant is screw fastening , the formation of a film with the same space at the same time is very consistent with the surface . Meanwhile , the thinner the film , the greater resilience , the better seal.
4 , flow and pressure resistance
Using liquid metal sealant joints , gaps are generally less than 0.1mm , and the liquid sealant is a liquid of high viscosity , it is difficult to flow , thereby maintaining its good sealing .
5, the volume change and mobility
Solid gasket leak-proof effect is the compression of the cushion sheet elastic deformation . The liquid sealant is leakproof volume in the compression and stretching deformation , it does not exist solid gasket compression deformation, so there is no compression fatigue , pull tight seals elastic failure , stress relaxation and other phenomena , and it is always connected adhesion of the interface , the interface can be prevented leakage .
2013年9月9日星期一
Sunshine plate sealing tape Caution
Sunshine board the original tape. Only used for temporary protection sheet edge is intolerant of aging in the installation project, according to size cutting board , after cutting the tape must be project-specific installation requirements of regulations by the end wire seals plate bore grid, replacing the original tape down . Special tape installation works should good weather resistance , long-term use without losing its adhesion and mechanical strength , the installation operation, when taping .
To note the following:
( A ) ensure the plate edges are smooth .
( 2 ) to all wells blown clean , compressed air must be free of any impurities and dry .
( 3 ) To guarantee that using profiles, metal cover , protective ends of the U-shaped groove of the tape completely covers the installation is complete, there should not be exposed parts.
( 4 ) was added to the pre- installed before installing the final tape to check whether the loss , metal seal damage is found tape , must be replaced.
To note the following:
( A ) ensure the plate edges are smooth .
( 2 ) to all wells blown clean , compressed air must be free of any impurities and dry .
( 3 ) To guarantee that using profiles, metal cover , protective ends of the U-shaped groove of the tape completely covers the installation is complete, there should not be exposed parts.
( 4 ) was added to the pre- installed before installing the final tape to check whether the loss , metal seal damage is found tape , must be replaced.
Brief sealant to save money
Recently , the famous American expert author doors sealant Analysis of how to reduce costs. Here we have to introduce the following is relatively feasible way to reduce the amount of binder . However, there is a sentence I still want to reiterate advice : Although the choice of the sealing glue to consider the cost issue , however, the choice really suitable for their sealing glue also need to consider aspects , should not suffer a great deal because they are cheap . Perhaps, inexpensive sealant can save a lot of money for us , but its performance is not necessarily perfect , and afterwards perhaps to compensate for the cost of expensive loophole . Therefore , the choice of sealant before sealing adhesions best first senior expert advice to determine the best match their needs with sealing glue . Delineation of the optional sealing glue , you can follow these steps to cut your costs sealant :
1 Do not use too much glue seal security . Sometimes , manufacturers that use more glue sealing , adhesion effect is more ideal , in fact , this is a wrong idea. Excessive use of adhesives, adhesives not only increase the cost , in fact, the connection will also affect results. If you have questions about the amount of sealant , it is best to consult a sealant product sales personnel or the manufacturer's technical staff, they will provide you with practical solutions .
(2) reduce the fill point of application equipment . If you often need to replace the adhesive residue , then try to reduce the fill point of application equipment .
3 prolong the shelf life of the sealing glue . If one could ever use a whole bucket of sealant, so as soon as possible to re- packaged sealant containers to prevent product freezing or evaporation .
4 Check the pressure equipment . If the device is too much pressure will cause the sealant waste and affect the life of the pump . Here you need to do is to determine a reasonable pressure setting , and to ensure strict compliance with the equipment operator settings .
5 regular testing and maintenance of your equipment . Regular maintenance will improve equipment performance , in addition, can also reduce equipment maintenance costs.
6 compared to other sealing products , water-based sealants can be significant cost savings. Therefore , the choice of sealant products , try to give priority to water seal products. Water-based sealing products easy to clean and easy to use conditions , unlike chemical truck seal glue , long-term maintenance of the equipment is required on the high investment .
7 repeated use of purified water and cleaning water . For the production of the device configuration can be used repeatedly washing water system, water purification and repeated use of the washing water .
1 Do not use too much glue seal security . Sometimes , manufacturers that use more glue sealing , adhesion effect is more ideal , in fact , this is a wrong idea. Excessive use of adhesives, adhesives not only increase the cost , in fact, the connection will also affect results. If you have questions about the amount of sealant , it is best to consult a sealant product sales personnel or the manufacturer's technical staff, they will provide you with practical solutions .
(2) reduce the fill point of application equipment . If you often need to replace the adhesive residue , then try to reduce the fill point of application equipment .
3 prolong the shelf life of the sealing glue . If one could ever use a whole bucket of sealant, so as soon as possible to re- packaged sealant containers to prevent product freezing or evaporation .
4 Check the pressure equipment . If the device is too much pressure will cause the sealant waste and affect the life of the pump . Here you need to do is to determine a reasonable pressure setting , and to ensure strict compliance with the equipment operator settings .
5 regular testing and maintenance of your equipment . Regular maintenance will improve equipment performance , in addition, can also reduce equipment maintenance costs.
6 compared to other sealing products , water-based sealants can be significant cost savings. Therefore , the choice of sealant products , try to give priority to water seal products. Water-based sealing products easy to clean and easy to use conditions , unlike chemical truck seal glue , long-term maintenance of the equipment is required on the high investment .
7 repeated use of purified water and cleaning water . For the production of the device configuration can be used repeatedly washing water system, water purification and repeated use of the washing water .
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