![\"\"](\"https:\/\/zecovalve.com\/wp-content\/uploads\/2022\/01\/20220105083122-61d5575ae65f4.jpg\")
<\/figure>\n<\/div>\n\n\nComo funciona uma v\u00e1lvula de diafragma?<\/h2>\n\n\n\n
A pot\u00eancia operacional de uma v\u00e1lvula de diafragma pode vir de diversas fontes. Uma v\u00e1lvula de diafragma pneum\u00e1tica usa press\u00e3o de ar para abri-la ou fech\u00e1-la. \u00c0s vezes, um solen\u00f3ide \u2013 um componente met\u00e1lico enrolado em fio que pode produzir um campo magn\u00e9tico na presen\u00e7a de eletricidade \u2013 \u00e9 empregado para acionar a v\u00e1lvula. Outras vezes, pode ser operado manualmente. Al\u00e9m disso, a press\u00e3o hidr\u00e1ulica tamb\u00e9m \u00e9 comumente utilizada.<\/p>\n\n\n\n
Tipos de v\u00e1lvulas de diafragma<\/h2>\n\n\n\n- V\u00e1lvulas de diafragma tipo Weir<\/strong>
- A v\u00e1lvula de diafragma tipo vertedor \u00e9 um dos designs mais comuns dispon\u00edveis e \u00e9 mostrada na Figura 2 acima. O design de l\u00e1bio\/sela elevado \u00e9 mais adequado para controle de fluxo pequeno e \u00e9 mantido \u00e0 prova de vazamentos gra\u00e7as \u00e0 tampa sobre o diafragma e o atuador. Este projeto \u00e9 ideal para l\u00edquidos e gases perigosos ou corrosivos, pois qualquer falha na membrana ser\u00e1 mantida contida por esta tampa. Al\u00e9m disso, o corpo inclinado torna esta v\u00e1lvula inerentemente autodrenante, mas esta drenagem pode ocorrer em ambas as dire\u00e7\u00f5es da v\u00e1lvula, o que pode n\u00e3o ser ideal para algumas aplica\u00e7\u00f5es. A v\u00e1lvula tipo vertedor \u00e9 especificada principalmente para fluidos limpos e homog\u00eaneos, pois lamas viscosas e sedimentos podem se acumular em ambos os lados da sela. Eles s\u00e3o encontrados com mais frequ\u00eancia em processos como aplica\u00e7\u00f5es aliment\u00edcias\/qu\u00edmicas, de produ\u00e7\u00e3o de g\u00e1s, corrosivas e de \u00e1gua.<\/li><\/ul><\/li>
- V\u00e1lvulas de diafragma do tipo direto<\/strong>
- A v\u00e1lvula de diafragma direta \u00e9 estruturalmente semelhante aos tipos de a\u00e7ude; no entanto, n\u00e3o cont\u00e9m a sela caracter\u00edstica e, em vez disso, possui um caminho completamente reto. Suas membranas s\u00e3o normalmente mais flex\u00edveis e permitem uma dist\u00e2ncia maior de deslocamento, pois devem tocar a parte inferior da v\u00e1lvula. Essas v\u00e1lvulas devem frequentemente passar por manuten\u00e7\u00e3o\/substitu\u00eddas, pois sua vida \u00fatil \u00e9 normalmente menor do que os projetos do tipo barragem devido \u00e0s suas membranas mais flex\u00edveis. As v\u00e1lvulas de diafragma direto s\u00e3o usadas para polpas, fluidos viscosos e outras aplica\u00e7\u00f5es onde o bloqueio deve ser reduzido. Eles tamb\u00e9m s\u00e3o \u00fateis para regimes de fluxo bidirecionais, pois n\u00e3o h\u00e1 sela para impedir a mudan\u00e7a r\u00e1pida da entrada para a sa\u00edda.<\/li><\/ul><\/li><\/ul>\n\n\n\n
Vantagens das v\u00e1lvulas de diafragma?<\/h2>\n\n\n\n- As v\u00e1lvulas de diafragma tamb\u00e9m podem ser usadas para servi\u00e7os de estrangulamento.<\/li>
- Suas caracter\u00edsticas de estrangulamento s\u00e3o essencialmente as de uma v\u00e1lvula de abertura r\u00e1pida devido \u00e0 grande \u00e1rea de fechamento ao longo da sede.<\/li>
- Uma v\u00e1lvula de diafragma tipo vertedor est\u00e1 dispon\u00edvel para controlar pequenos fluxos.<\/li>
- As v\u00e1lvulas de diafragma s\u00e3o particularmente adequadas para o manuseio de fluidos corrosivos, lamas fibrosas, fluidos radioativos ou outros fluidos que devem permanecer livres de contamina\u00e7\u00e3o.<\/li>
- O mecanismo operacional de uma v\u00e1lvula de diafragma n\u00e3o fica exposto ao meio dentro da tubula\u00e7\u00e3o. Fluidos pegajosos ou viscosos n\u00e3o podem entrar no cap\u00f4 e interferir no mecanismo operacional.<\/li>
- Muitos fluidos que obstruiriam, corroeriam ou obstruiriam as pe\u00e7as funcionais da maioria dos outros tipos de v\u00e1lvulas passar\u00e3o por uma v\u00e1lvula de diafragma sem causar problemas. Por outro lado, os lubrificantes usados para o mecanismo de opera\u00e7\u00e3o n\u00e3o podem contaminar o fluido que est\u00e1 sendo manuseado.<\/li>
- N\u00e3o h\u00e1 veda\u00e7\u00f5es para manuten\u00e7\u00e3o e nenhuma possibilidade de vazamento na haste das v\u00e1lvulas.<\/li><\/ul>\n\n\n\n\n
Etiquetas relacionadas :<\/h2>\n\n\n\n\n\nV\u00e1lvula ZECO<\/a>\n\n<\/div>\n\n\n\n\nDiferen\u00e7a entre a v\u00e1lvula de gaveta e a v\u00e1lvula de borboleta<\/a>\n\n<\/div>\n\n\n\n\nO que s\u00e3o v\u00e1lvulas globo?<\/a>\n\n<\/div>\n\n\n\n\nV\u00e1lvula de gaveta de acionamento manual Fabricante<\/a>\n\n<\/div>\n\n\n\n\nO que \u00e9 uma v\u00e1lvula de gaveta?<\/a>\n\n<\/div>\n\n\n\n\nF\u00e1brica de v\u00e1lvulas redutoras de press\u00e3o de Xangai<\/a>\n\n<\/div>\n\n\n\n\nO que s\u00e3o v\u00e1lvulas de controlo autom\u00e1ticas?<\/a>\n\n<\/div>\n\n\n\n\nV\u00e1lvula de Globo vs V\u00e1lvula de Esfera<\/a>\n\n<\/div>\n\n\n\n\nFornecedor de v\u00e1lvula gaveta de 12 polegadas<\/a>\n\n<\/div>\n\n\n\n\nMateriais termopl\u00e1sticos como sede de v\u00e1lvula esf\u00e9rica e sede de v\u00e1lvula borboleta<\/a>\n\n<\/div>","protected":false},"excerpt":{"rendered":"As v\u00e1lvulas de diafragma n\u00e3o s\u00e3o, na maioria das situa\u00e7\u00f5es, uma considera\u00e7\u00e3o importante. Mas quando uma v\u00e1lvula pode melhorar seu desempenho em processos posteriores, ela\u2026 Ler mais<\/a><\/p>","protected":false},"author":2,"featured_media":13348,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_generate-full-width-content":"","kt_blocks_editor_width":"","footnotes":""},"categories":[1],"tags":[2702,2704,2703,3205],"class_list":["post-3059","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-uncategorized","tag-diaphragm-valve","tag-diaphragm-valve-diagram","tag-diaphragm-valve-function","tag-diaphragm-valve-manufacturers","generate-columns","tablet-grid-50","mobile-grid-100","grid-parent","grid-50"],"featured_image_src_large":["https:\/\/zecovalve.com\/wp-content\/uploads\/2022\/01\/20220105083122-61d5575ae65f4.jpg",924,1004,false],"author_info":{"display_name":"Jerry","author_link":"https:\/\/zecovalve.com\/pt\/author\/jerry"},"comment_info":0,"category_info":[{"term_id":1,"name":"Uncategorized","slug":"uncategorized","term_group":0,"term_taxonomy_id":1,"taxonomy":"category","description":"","parent":0,"count":452,"filter":"raw","cat_ID":1,"category_count":452,"category_description":"","cat_name":"Uncategorized","category_nicename":"uncategorized","category_parent":0}],"tag_info":[{"term_id":2702,"name":"Diaphragm Valve","slug":"diaphragm-valve","term_group":0,"term_taxonomy_id":2702,"taxonomy":"post_tag","description":"","parent":0,"count":3,"filter":"raw"},{"term_id":2704,"name":"diaphragm valve diagram","slug":"diaphragm-valve-diagram","term_group":0,"term_taxonomy_id":2704,"taxonomy":"post_tag","description":"","parent":0,"count":2,"filter":"raw"},{"term_id":2703,"name":"Diaphragm Valve Function","slug":"diaphragm-valve-function","term_group":0,"term_taxonomy_id":2703,"taxonomy":"post_tag","description":"\r\n\r\n\r\n\r\nGET DIAPHRAGM VALVE DIAGRAM INFORMATION<\/strong><\/a>\r\n\r\n\r\n\r\n\r\nWhat is a Diaphragm Valve?<\/h2>\r\n\r\n\r\n\r\n\r\nDiaphragm valves get their name from a flexible disc that comes into contact with a seat at the top of the valve body to form a seal. A diaphragm is a flexible, pressure-responsive element that transmits force to open, close, or control a valve. Diaphragm valves are related to pinch valves, but use an elastomeric diaphragm, instead of an elastomeric liner in the valve body, to separate the flow stream from the closure element.\r\n\r\n\r\n\r\n\r\n![\"\"](\"https:\/\/zecovalve.com\/wp-content\/uploads\/2022\/07\/20220708083634-62c7ec92aba44.jpg\")
<\/figure>\r\n\r\n\r\n\r\nHow do Diaphragm Valves Work?<\/h2>\r\n\r\n\r\n\r\n\r\nDiaphragm valves are simple in construction and operation. A valve actuator is in contact with the inner membrane (or \u201cdiaphragm\u201d) of the valve in its open position. When the user desires the valve to be shut, the actuator is pressed and\/or turned and the membrane is pushed into the edge of the solid damn, closing the valve. Certain diaphragm valves can also have half open\/restricted positions where the membrane is partially closed, allowing a throttled flow through the valve. In the next section, we will examine the broad categories of diaphragm valves and where they are most useful.\r\n\r\n\r\n\r\n\r\nTypes of Diaphragm Valves<\/h2>\r\n\r\n\r\n\r\nWeir-Type Diaphragm Valves<\/h3>\r\n\r\n\r\n\r\n\r\nThe weir-type diaphragm valve is one of the most common designs available and is what is shown in Figure 2, above. The raised lip\/saddle design is best suited for small flow control and is kept leak-proof thanks to the bonnet over the diaphragm and actuator. This design is optimal for dangerous or corrosive liquid and gas, as any failure with the membrane will be kept contained by this bonnet. Also, the sloped body makes this valve inherently self-draining, but this draining can happen in both valve directions which may not be optimal for some applications. The weir-type valve is mostly specified for clean, homogenous fluids, as viscous slurries and sediments may build up on either side of the saddle. They are most often found in processes such as food\/chemical, gas production, corrosive, and water applications.\r\n\r\n\r\n\r\n\r\nStraight Through Type Diaphragm Valves<\/h3>\r\n\r\n\r\n\r\n\r\nThe straight-through diaphragm valve is structurally similar to weir-types; however, it does not contain the characteristic saddle and instead has a completely straight pathway. Their membranes are typically more flexible and allow for farther travel distance, as it must touch the very bottom of the valve. These valves must often be serviced\/replaced, as their lifespan is typically less than weir-type designs due to their more flexible membranes. Straight-through diaphragm valves are used for slurries, viscous fluids, and other applications where blocking must be reduced. They are also useful for bi-directional flow regimes, as there is no saddle to impede swift changing from inlet to outlet.\r\n\r\n\r\n\r\n\r\nDiaphragm Valve Parts<\/h2>\r\n\r\n\r\n\r\n\r\nThe components of diaphragm valves are the following:\r\n\r\n\r\n\r\n\r\nDiaphragm Valve Bonnet<\/h3>\r\n\r\n\r\n\r\n\r\nThe bonnet serves as the top cover and is bolted to the valve body. It protects the compressor, stem, diaphragm, and other non-wetted components of the diaphragm valve.\r\n\r\n\r\n\r\n\r\nDiaphragm Valve Body<\/h3>\r\n\r\n\r\n\r\n\r\nThe valve body is the component directly connected to the pipeline wherein the fluid passes. The flow area inside the valve body depends on the type of diaphragm valve.\r\n\r\n\r\n\r\n\r\n\r\nBoth the valve body and bonnet are constructed from strong, rigid, and corrosive resistant materials.\r\n\r\n\r\n\r\n\r\nDiaphragm Valve Diaphragm<\/h3>\r\n\r\n\r\n\r\n\r\nThe diaphragm is made from a highly elastic polymeric disc that moves down to touch the bottom of the valve body to limit or obstruct the passage of fluid. The diaphragm lifts if the fluid flow rate is to be increased or the valve is to be fully opened. The fluid flows underneath the diaphragm. However, this component limits the valve\u2019s operating temperature and pressure due to the diaphragm\u2019s material and structure. It must also be replaced periodically since its mechanical properties degrade during usage.\r\n\r\n\r\n\r\n\r\n\r\nThe diaphragm isolates the non-wetted components (compressor, stem, and actuator) from the flowing media. Therefore, solids and viscous fluids are less likely to interfere with the operating mechanism of the diaphragm valve. This also protects the non-wetted components from corrosion. Conversely, the fluid in the pipeline will not be contaminated with the lubricant used in operating the valve.\r\n\r\n\r\n\r\n\r\nMaterial of Diaphragm Valve Diaphragm<\/h4>\r\n\r\n\r\n\r\n\r\nUnlined or Rubber Lined Type<\/strong>\r\n\r\n\r\n\r\n\r\n\r\n \t- NR\/Natural Rubber<\/li>\r\n \t
- NBR\/Nitrile\/Buna-N<\/li>\r\n \t
- EPDM<\/li>\r\n \t
- FKM\/Viton<\/li>\r\n \t
- BUNA-N<\/li>\r\n \t
- SI\/Silicone rubber<\/li>\r\n \t
- Leather<\/li>\r\n<\/ul>\r\n\r\n\r\n\r\n\r\nFluorine Plastic Type<\/strong>\r\n\r\n\r\n\r\n\r\n
\r\n \t- FEP, with EPDM backing<\/li>\r\n \t
- PTFE, with EPDM backing<\/li>\r\n \t
- PFA, with EPDM backing<\/li>\r\n<\/ul>\r\n\r\n\r\n\r\n
Diaphragm Valve Compressor<\/h3>\r\n\r\n\r\n\r\n\r\nThe compressor is a disc that lies between the valve stem and the diaphragm. It supports the diaphragm valve and distributes the forces from the stem during linear movement. The compressor design is optimized to provide better flow throttling and control.\r\n\r\n\r\n\r\n\r\nDiaphragm Valve Stem<\/h3>\r\n\r\n\r\n\r\n\r\nThe stem is a vertical shaft connected to the compressor that exerts linear motion to move both compressor and diaphragm, thus operating the diaphragm valve. It transmits the motion exerted by the actuator. Diaphragm valves can either have piston- or threaded-type stems. As the name implies, piston-type valves are moved by a piston assembly inside the bonnet, with the valve stem likely acting as the piston rod. This type requires linear force exerted by fluid pressure. Threaded stem valves have a matching stem nut. This type requires torque to linearly move the stem, as well as lubrication for smooth motion.\r\n\r\n\r\n\r\n\r\n\r\nThe threaded stems of diaphragm valves can have a rising or non-rising mechanism:\r\n\r\n\r\n\r\n\r\n\r\n \t- Rising Stem<\/strong>: Rising stems or indicating stems extend their length up to the handwheel. As the handwheel is turned, the stem rises or descends to open or close the valve, respectively. Hence, it is easier to determine the extent to which the valve is opened by looking at the amount of stem exposed. However, rising stems take up more space than non-rising stems.<\/li>\r\n \t
- Non-Rising Stem:<\/strong> Non-rising stems or non-indicating stems are rotated to open or close the valve, but it does not cause the stem to move up or down. Non-rising stem valves are used in limited spaces, such as in underground piping systems.<\/li>\r\n<\/ul>\r\n\r\n\r\n\r\n
Advantages and Disadvantages of Diaphragm Valves<\/h2>\r\n\r\n\r\n\r\n\r\n
- A v\u00e1lvula de diafragma tipo vertedor \u00e9 um dos designs mais comuns dispon\u00edveis e \u00e9 mostrada na Figura 2 acima. O design de l\u00e1bio\/sela elevado \u00e9 mais adequado para controle de fluxo pequeno e \u00e9 mantido \u00e0 prova de vazamentos gra\u00e7as \u00e0 tampa sobre o diafragma e o atuador. Este projeto \u00e9 ideal para l\u00edquidos e gases perigosos ou corrosivos, pois qualquer falha na membrana ser\u00e1 mantida contida por esta tampa. Al\u00e9m disso, o corpo inclinado torna esta v\u00e1lvula inerentemente autodrenante, mas esta drenagem pode ocorrer em ambas as dire\u00e7\u00f5es da v\u00e1lvula, o que pode n\u00e3o ser ideal para algumas aplica\u00e7\u00f5es. A v\u00e1lvula tipo vertedor \u00e9 especificada principalmente para fluidos limpos e homog\u00eaneos, pois lamas viscosas e sedimentos podem se acumular em ambos os lados da sela. Eles s\u00e3o encontrados com mais frequ\u00eancia em processos como aplica\u00e7\u00f5es aliment\u00edcias\/qu\u00edmicas, de produ\u00e7\u00e3o de g\u00e1s, corrosivas e de \u00e1gua.<\/li><\/ul><\/li>
- V\u00e1lvulas de diafragma do tipo direto<\/strong>
- A v\u00e1lvula de diafragma direta \u00e9 estruturalmente semelhante aos tipos de a\u00e7ude; no entanto, n\u00e3o cont\u00e9m a sela caracter\u00edstica e, em vez disso, possui um caminho completamente reto. Suas membranas s\u00e3o normalmente mais flex\u00edveis e permitem uma dist\u00e2ncia maior de deslocamento, pois devem tocar a parte inferior da v\u00e1lvula. Essas v\u00e1lvulas devem frequentemente passar por manuten\u00e7\u00e3o\/substitu\u00eddas, pois sua vida \u00fatil \u00e9 normalmente menor do que os projetos do tipo barragem devido \u00e0s suas membranas mais flex\u00edveis. As v\u00e1lvulas de diafragma direto s\u00e3o usadas para polpas, fluidos viscosos e outras aplica\u00e7\u00f5es onde o bloqueio deve ser reduzido. Eles tamb\u00e9m s\u00e3o \u00fateis para regimes de fluxo bidirecionais, pois n\u00e3o h\u00e1 sela para impedir a mudan\u00e7a r\u00e1pida da entrada para a sa\u00edda.<\/li><\/ul><\/li><\/ul>\n\n\n\n
Vantagens das v\u00e1lvulas de diafragma?<\/h2>\n\n\n\n
- As v\u00e1lvulas de diafragma tamb\u00e9m podem ser usadas para servi\u00e7os de estrangulamento.<\/li>
- Suas caracter\u00edsticas de estrangulamento s\u00e3o essencialmente as de uma v\u00e1lvula de abertura r\u00e1pida devido \u00e0 grande \u00e1rea de fechamento ao longo da sede.<\/li>
- Uma v\u00e1lvula de diafragma tipo vertedor est\u00e1 dispon\u00edvel para controlar pequenos fluxos.<\/li>
- As v\u00e1lvulas de diafragma s\u00e3o particularmente adequadas para o manuseio de fluidos corrosivos, lamas fibrosas, fluidos radioativos ou outros fluidos que devem permanecer livres de contamina\u00e7\u00e3o.<\/li>
- O mecanismo operacional de uma v\u00e1lvula de diafragma n\u00e3o fica exposto ao meio dentro da tubula\u00e7\u00e3o. Fluidos pegajosos ou viscosos n\u00e3o podem entrar no cap\u00f4 e interferir no mecanismo operacional.<\/li>
- Muitos fluidos que obstruiriam, corroeriam ou obstruiriam as pe\u00e7as funcionais da maioria dos outros tipos de v\u00e1lvulas passar\u00e3o por uma v\u00e1lvula de diafragma sem causar problemas. Por outro lado, os lubrificantes usados para o mecanismo de opera\u00e7\u00e3o n\u00e3o podem contaminar o fluido que est\u00e1 sendo manuseado.<\/li>
- N\u00e3o h\u00e1 veda\u00e7\u00f5es para manuten\u00e7\u00e3o e nenhuma possibilidade de vazamento na haste das v\u00e1lvulas.<\/li><\/ul>\n\n\n\n\n
Etiquetas relacionadas :<\/h2>\n\n\n\n\n
\nV\u00e1lvula ZECO<\/a>\n\n<\/div>\n\n\n\n\nDiferen\u00e7a entre a v\u00e1lvula de gaveta e a v\u00e1lvula de borboleta<\/a>\n\n<\/div>\n\n\n\n\nO que s\u00e3o v\u00e1lvulas globo?<\/a>\n\n<\/div>\n\n\n\n\nV\u00e1lvula de gaveta de acionamento manual Fabricante<\/a>\n\n<\/div>\n\n\n\n\nO que \u00e9 uma v\u00e1lvula de gaveta?<\/a>\n\n<\/div>\n\n\n\n\nF\u00e1brica de v\u00e1lvulas redutoras de press\u00e3o de Xangai<\/a>\n\n<\/div>\n\n\n\n\nO que s\u00e3o v\u00e1lvulas de controlo autom\u00e1ticas?<\/a>\n\n<\/div>\n\n\n\n\nV\u00e1lvula de Globo vs V\u00e1lvula de Esfera<\/a>\n\n<\/div>\n\n\n\n\nFornecedor de v\u00e1lvula gaveta de 12 polegadas<\/a>\n\n<\/div>\n\n\n\n\nMateriais termopl\u00e1sticos como sede de v\u00e1lvula esf\u00e9rica e sede de v\u00e1lvula borboleta<\/a>\n\n<\/div>","protected":false},"excerpt":{"rendered":"As v\u00e1lvulas de diafragma n\u00e3o s\u00e3o, na maioria das situa\u00e7\u00f5es, uma considera\u00e7\u00e3o importante. Mas quando uma v\u00e1lvula pode melhorar seu desempenho em processos posteriores, ela\u2026 Ler mais<\/a><\/p>","protected":false},"author":2,"featured_media":13348,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_generate-full-width-content":"","kt_blocks_editor_width":"","footnotes":""},"categories":[1],"tags":[2702,2704,2703,3205],"class_list":["post-3059","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-uncategorized","tag-diaphragm-valve","tag-diaphragm-valve-diagram","tag-diaphragm-valve-function","tag-diaphragm-valve-manufacturers","generate-columns","tablet-grid-50","mobile-grid-100","grid-parent","grid-50"],"featured_image_src_large":["https:\/\/zecovalve.com\/wp-content\/uploads\/2022\/01\/20220105083122-61d5575ae65f4.jpg",924,1004,false],"author_info":{"display_name":"Jerry","author_link":"https:\/\/zecovalve.com\/pt\/author\/jerry"},"comment_info":0,"category_info":[{"term_id":1,"name":"Uncategorized","slug":"uncategorized","term_group":0,"term_taxonomy_id":1,"taxonomy":"category","description":"","parent":0,"count":452,"filter":"raw","cat_ID":1,"category_count":452,"category_description":"","cat_name":"Uncategorized","category_nicename":"uncategorized","category_parent":0}],"tag_info":[{"term_id":2702,"name":"Diaphragm Valve","slug":"diaphragm-valve","term_group":0,"term_taxonomy_id":2702,"taxonomy":"post_tag","description":"","parent":0,"count":3,"filter":"raw"},{"term_id":2704,"name":"diaphragm valve diagram","slug":"diaphragm-valve-diagram","term_group":0,"term_taxonomy_id":2704,"taxonomy":"post_tag","description":"","parent":0,"count":2,"filter":"raw"},{"term_id":2703,"name":"Diaphragm Valve Function","slug":"diaphragm-valve-function","term_group":0,"term_taxonomy_id":2703,"taxonomy":"post_tag","description":"\r\n\r\n\r\n\r\nGET DIAPHRAGM VALVE DIAGRAM INFORMATION<\/strong><\/a>\r\n\r\n\r\n\r\n\r\n
What is a Diaphragm Valve?<\/h2>\r\n\r\n\r\n\r\n\r\nDiaphragm valves get their name from a flexible disc that comes into contact with a seat at the top of the valve body to form a seal. A diaphragm is a flexible, pressure-responsive element that transmits force to open, close, or control a valve. Diaphragm valves are related to pinch valves, but use an elastomeric diaphragm, instead of an elastomeric liner in the valve body, to separate the flow stream from the closure element.\r\n\r\n\r\n\r\n\r\n
<\/figure>\r\n\r\n\r\n\r\nHow do Diaphragm Valves Work?<\/h2>\r\n\r\n\r\n\r\n\r\nDiaphragm valves are simple in construction and operation. A valve actuator is in contact with the inner membrane (or \u201cdiaphragm\u201d) of the valve in its open position. When the user desires the valve to be shut, the actuator is pressed and\/or turned and the membrane is pushed into the edge of the solid damn, closing the valve. Certain diaphragm valves can also have half open\/restricted positions where the membrane is partially closed, allowing a throttled flow through the valve. In the next section, we will examine the broad categories of diaphragm valves and where they are most useful.\r\n\r\n\r\n\r\n\r\n
Types of Diaphragm Valves<\/h2>\r\n\r\n\r\n\r\n
Weir-Type Diaphragm Valves<\/h3>\r\n\r\n\r\n\r\n\r\nThe weir-type diaphragm valve is one of the most common designs available and is what is shown in Figure 2, above. The raised lip\/saddle design is best suited for small flow control and is kept leak-proof thanks to the bonnet over the diaphragm and actuator. This design is optimal for dangerous or corrosive liquid and gas, as any failure with the membrane will be kept contained by this bonnet. Also, the sloped body makes this valve inherently self-draining, but this draining can happen in both valve directions which may not be optimal for some applications. The weir-type valve is mostly specified for clean, homogenous fluids, as viscous slurries and sediments may build up on either side of the saddle. They are most often found in processes such as food\/chemical, gas production, corrosive, and water applications.\r\n\r\n\r\n\r\n\r\n
Straight Through Type Diaphragm Valves<\/h3>\r\n\r\n\r\n\r\n\r\nThe straight-through diaphragm valve is structurally similar to weir-types; however, it does not contain the characteristic saddle and instead has a completely straight pathway. Their membranes are typically more flexible and allow for farther travel distance, as it must touch the very bottom of the valve. These valves must often be serviced\/replaced, as their lifespan is typically less than weir-type designs due to their more flexible membranes. Straight-through diaphragm valves are used for slurries, viscous fluids, and other applications where blocking must be reduced. They are also useful for bi-directional flow regimes, as there is no saddle to impede swift changing from inlet to outlet.\r\n\r\n\r\n\r\n\r\n
Diaphragm Valve Parts<\/h2>\r\n\r\n\r\n\r\n\r\nThe components of diaphragm valves are the following:\r\n\r\n\r\n\r\n\r\n
Diaphragm Valve Bonnet<\/h3>\r\n\r\n\r\n\r\n\r\nThe bonnet serves as the top cover and is bolted to the valve body. It protects the compressor, stem, diaphragm, and other non-wetted components of the diaphragm valve.\r\n\r\n\r\n\r\n\r\n
Diaphragm Valve Body<\/h3>\r\n\r\n\r\n\r\n\r\nThe valve body is the component directly connected to the pipeline wherein the fluid passes. The flow area inside the valve body depends on the type of diaphragm valve.\r\n\r\n\r\n\r\n\r\n\r\nBoth the valve body and bonnet are constructed from strong, rigid, and corrosive resistant materials.\r\n\r\n\r\n\r\n\r\n
Diaphragm Valve Diaphragm<\/h3>\r\n\r\n\r\n\r\n\r\nThe diaphragm is made from a highly elastic polymeric disc that moves down to touch the bottom of the valve body to limit or obstruct the passage of fluid. The diaphragm lifts if the fluid flow rate is to be increased or the valve is to be fully opened. The fluid flows underneath the diaphragm. However, this component limits the valve\u2019s operating temperature and pressure due to the diaphragm\u2019s material and structure. It must also be replaced periodically since its mechanical properties degrade during usage.\r\n\r\n\r\n\r\n\r\n\r\nThe diaphragm isolates the non-wetted components (compressor, stem, and actuator) from the flowing media. Therefore, solids and viscous fluids are less likely to interfere with the operating mechanism of the diaphragm valve. This also protects the non-wetted components from corrosion. Conversely, the fluid in the pipeline will not be contaminated with the lubricant used in operating the valve.\r\n\r\n\r\n\r\n\r\n
Material of Diaphragm Valve Diaphragm<\/h4>\r\n\r\n\r\n\r\n\r\nUnlined or Rubber Lined Type<\/strong>\r\n\r\n\r\n\r\n\r\n
- \r\n \t
- NR\/Natural Rubber<\/li>\r\n \t
- NBR\/Nitrile\/Buna-N<\/li>\r\n \t
- EPDM<\/li>\r\n \t
- FKM\/Viton<\/li>\r\n \t
- BUNA-N<\/li>\r\n \t
- SI\/Silicone rubber<\/li>\r\n \t
- Leather<\/li>\r\n<\/ul>\r\n\r\n\r\n\r\n\r\nFluorine Plastic Type<\/strong>\r\n\r\n\r\n\r\n\r\n
- \r\n \t
- FEP, with EPDM backing<\/li>\r\n \t
- PTFE, with EPDM backing<\/li>\r\n \t
- PFA, with EPDM backing<\/li>\r\n<\/ul>\r\n\r\n\r\n\r\n
Diaphragm Valve Compressor<\/h3>\r\n\r\n\r\n\r\n\r\nThe compressor is a disc that lies between the valve stem and the diaphragm. It supports the diaphragm valve and distributes the forces from the stem during linear movement. The compressor design is optimized to provide better flow throttling and control.\r\n\r\n\r\n\r\n\r\n
Diaphragm Valve Stem<\/h3>\r\n\r\n\r\n\r\n\r\nThe stem is a vertical shaft connected to the compressor that exerts linear motion to move both compressor and diaphragm, thus operating the diaphragm valve. It transmits the motion exerted by the actuator. Diaphragm valves can either have piston- or threaded-type stems. As the name implies, piston-type valves are moved by a piston assembly inside the bonnet, with the valve stem likely acting as the piston rod. This type requires linear force exerted by fluid pressure. Threaded stem valves have a matching stem nut. This type requires torque to linearly move the stem, as well as lubrication for smooth motion.\r\n\r\n\r\n\r\n\r\n\r\nThe threaded stems of diaphragm valves can have a rising or non-rising mechanism:\r\n\r\n\r\n\r\n\r\n
- \r\n \t
- Rising Stem<\/strong>: Rising stems or indicating stems extend their length up to the handwheel. As the handwheel is turned, the stem rises or descends to open or close the valve, respectively. Hence, it is easier to determine the extent to which the valve is opened by looking at the amount of stem exposed. However, rising stems take up more space than non-rising stems.<\/li>\r\n \t
- Non-Rising Stem:<\/strong> Non-rising stems or non-indicating stems are rotated to open or close the valve, but it does not cause the stem to move up or down. Non-rising stem valves are used in limited spaces, such as in underground piping systems.<\/li>\r\n<\/ul>\r\n\r\n\r\n\r\n
Advantages and Disadvantages of Diaphragm Valves<\/h2>\r\n\r\n\r\n\r\n
\r\n - Non-Rising Stem:<\/strong> Non-rising stems or non-indicating stems are rotated to open or close the valve, but it does not cause the stem to move up or down. Non-rising stem valves are used in limited spaces, such as in underground piping systems.<\/li>\r\n<\/ul>\r\n\r\n\r\n\r\n
- Rising Stem<\/strong>: Rising stems or indicating stems extend their length up to the handwheel. As the handwheel is turned, the stem rises or descends to open or close the valve, respectively. Hence, it is easier to determine the extent to which the valve is opened by looking at the amount of stem exposed. However, rising stems take up more space than non-rising stems.<\/li>\r\n \t
- A v\u00e1lvula de diafragma direta \u00e9 estruturalmente semelhante aos tipos de a\u00e7ude; no entanto, n\u00e3o cont\u00e9m a sela caracter\u00edstica e, em vez disso, possui um caminho completamente reto. Suas membranas s\u00e3o normalmente mais flex\u00edveis e permitem uma dist\u00e2ncia maior de deslocamento, pois devem tocar a parte inferior da v\u00e1lvula. Essas v\u00e1lvulas devem frequentemente passar por manuten\u00e7\u00e3o\/substitu\u00eddas, pois sua vida \u00fatil \u00e9 normalmente menor do que os projetos do tipo barragem devido \u00e0s suas membranas mais flex\u00edveis. As v\u00e1lvulas de diafragma direto s\u00e3o usadas para polpas, fluidos viscosos e outras aplica\u00e7\u00f5es onde o bloqueio deve ser reduzido. Eles tamb\u00e9m s\u00e3o \u00fateis para regimes de fluxo bidirecionais, pois n\u00e3o h\u00e1 sela para impedir a mudan\u00e7a r\u00e1pida da entrada para a sa\u00edda.<\/li><\/ul><\/li><\/ul>\n\n\n\n