Pneumatic fittings, tube connectors and quick couplers

A push-in fitting retains and seals a prepared tube end. A compression fitting uses a nut and sleeve or ferrule arrangement. A quick coupling separates a line through matching socket and plug halves. These names describe different interfaces, so specify the mechanism before comparing parts. Confirm the exact tubing, mating connection and assembly instructions for the proposed variant; similar appearance does not establish interchangeability.

Source: Parker Hannifin — Fluid System Connectors assembly guides · {"source_ids":["parker-assembly-guide","parker-compression-overview","parker-quick-coupling-guide"],"sources":[{"id":"parker-assembly-guide","publisher":"Parker Hannifin","title":"Fluid System Connectors assembly guides","url":"https://www.parker.com/content/dam/Parker-com/Literature/Brass-Products/bulletins/FSC-Assembly-Guides.pdf","accessed_at":"2026-10-30","access_status":"official PDF opened and readable; selected page screenshot requested","locator":"PDF pages 3-4: Push-to-Connect Fittings and Compression/Compress-Align/Poly-Tite/Hi-Duty assembly sections","excerpt":"Slide nut then sleeve onto tubing","supports_zh":"推入式与螺母/套环式装配机制不同；不同系列说明不同，本文不移植其圈数或扭矩作为通用安装值。"},{"id":"parker-compression-overview","publisher":"Parker Hannifin","title":"Fluid System Connectors quick reference guide","url":"https://www.parker.com/content/dam/Parker-com/Literature/Brass-Products/qrgs/Parker_FSC_Division_Overview_3500FSC-QRG.pdf","accessed_at":"2026-10-30","access_status":"official PDF opened and readable","locator":"August 2024; PDF page 19, printed page 19: Compression Fittings, Compress-Align, Poly-Tite and Hi-Duty","excerpt":"Pre-assembled with a captive sleeve","supports_zh":"卡套/压紧式连接具有不同套环、螺母和支撑结构，不能只凭卡套名称共用零件或安装步骤。品牌产品材料与参数不外推到本站。"},{"id":"parker-quick-coupling-guide","publisher":"Parker Hannifin","title":"Quick coupling selection and safety guide","url":"https://www.parker.com/content/dam/Parker-com/Literature/Brazil/Instrumentation/4220-Instrumentation-Quick-Couling---April-2008.pdf","accessed_at":"2026-10-30","access_status":"official historical PDF opened and readable; selected page screenshot requested","locator":"PDF/printed pages 31 and 35: series-specific mating profiles; page 46: coupling glossary; pages 47-48: selection and safety","excerpt":"Do not confuse burst pressure or other pressure values with rated pressure","supports_zh":"快换接头包含匹配的插头和插座；互换范围按系列/轮廓限定。选型需核对额定工作压力、介质与密封。2008年目录仅作结构和安全原则参考，不据此宣称当前供货或本站品牌互换。"}],"corpus_version":"2026-10-30.pneumatic-buying-guides.v1","corpus_sha256":"ea45a4ca2b449ccd1dd3c552729cc44972c43f124c3ea3955d769e706b9e0e25","hash_scope":"reviewed_editorial_corpus_file","scope":"General engineering guidance; not a certificate or specification for any listed product."} · Reviewed 2026-10-30

For a push-in tube connection, identify the outside diameter and state whether the units are metric or imperial. Also provide the tube material and manufacturer reference where known. The tube bore and the equipment port thread are separate details. If the sample is unidentified, request dimensional verification against the selected fitting's documentation rather than ordering from a photograph or an approximate size conversion.

Source: Festo — QS push-in fitting documentation · {"source_ids":["festo-qs-guide","festo-fitting-overview"],"sources":[{"id":"festo-qs-guide","publisher":"Festo","title":"QS push-in fitting documentation","url":"https://media.festo.com/media/204942_documentation.pdf","accessed_at":"2026-10-30","access_status":"official PDF opened and readable","locator":"June 2026; Characteristics and Pneumatic connection sections, PDF pages 2-4; product tables label tubing outside diameter","excerpt":"Check that the tubing connection is secure by pulling gently on the tube","supports_zh":"管接口按外径与适用管材选择；该系列G和R接口存在不同密封设计。其个别G/R组合说明不外推为任意品牌螺纹通配规则。"},{"id":"festo-fitting-overview","publisher":"Festo","title":"Pneumatic fittings overview","url":"https://www.festo.com/us/en/c/products/connectors-fittings-tubings/pneumatic-connectors/pneumatic-fittings-id_pim315","accessed_at":"2026-10-30","access_status":"official HTML opened and readable","locator":"Pneumatic fittings; connection types and selection by tubing material and diameter","excerpt":"choose fittings that match your hose material and diameter","supports_zh":"气动连接存在多种结构，管材与尺寸是选型输入；可支持采购询问维度，不支持本站型号的具体兼容性。"}],"corpus_version":"2026-10-30.pneumatic-buying-guides.v1","corpus_sha256":"ea45a4ca2b449ccd1dd3c552729cc44972c43f124c3ea3955d769e706b9e0e25","hash_scope":"reviewed_editorial_corpus_file","scope":"General engineering guidance; not a certificate or specification for any listed product."} · Reviewed 2026-10-30

Record male or female, the full thread designation, diameter, pitch and whether the thread is tapered or parallel. Identify the intended sealing surface as well. NPT, BSPT, BSPP and metric designations require separate checking. Use the equipment drawing and appropriate identification tools to resolve uncertainty; a thread that begins to engage is not sufficient evidence that the connection and seal are correct.

Source: Parker Hannifin — Instrument tube fitting installation manual · {"source_ids":["parker-thread-identification","iso-228-public-abstract"],"sources":[{"id":"parker-thread-identification","publisher":"Parker Hannifin","title":"Instrument tube fitting installation manual","url":"https://www.parker.com/content/dam/Parker-com/Literature/Instrumentation-Products-Division/Installation-Instructions/Parker_Tube_Fitting_Installation_Manual.pdf","accessed_at":"2026-10-30","access_status":"official PDF opened and readable; selected page screenshot requested","locator":"Bulletin 4200-B4, January 2023; PDF pages 63-65, printed pages 63-65: NPT, BSPT, BSPP and metric identification","excerpt":"A parallel thread form uses the threads for holding power only","supports_zh":"识别需区分螺纹标准、牙距、锥/直形状和密封结构；仅目测或试拧不足以确认配套。不是所有直螺纹都采用同一种密封件。"},{"id":"iso-228-public-abstract","publisher":"ISO","title":"ISO 228-1:2000 public abstract","url":"https://www.iso.org/standard/33777.html","accessed_at":"2026-10-30","access_status":"official public abstract opened and readable; full paid standard not accessed","locator":"Abstract: parallel threads, external sealing surfaces and appropriate seal","excerpt":"Both internal and external threads are parallel threads","supports_zh":"ISO 228-1范围内的平行管螺纹不依靠螺纹本身形成压力密封。只引用公开摘要，不声称审阅了付费标准全文或本站产品合规。"}],"corpus_version":"2026-10-30.pneumatic-buying-guides.v1","corpus_sha256":"ea45a4ca2b449ccd1dd3c552729cc44972c43f124c3ea3955d769e706b9e0e25","hash_scope":"reviewed_editorial_corpus_file","scope":"General engineering guidance; not a certificate or specification for any listed product."} · Reviewed 2026-10-30

The rear connection thread and the plug-to-socket mating profile describe different interfaces. Specify the existing coupling series, body size and mating profile, with drawings or clear photographs where available. Confirm both halves and the required shut-off function against current manufacturer documentation. A matching thread designation alone does not establish coupling compatibility, and this website makes no blanket cross-brand interchange claim.

Source: Parker Hannifin — Quick coupling selection and safety guide · {"source_ids":["parker-quick-coupling-guide"],"sources":[{"id":"parker-quick-coupling-guide","publisher":"Parker Hannifin","title":"Quick coupling selection and safety guide","url":"https://www.parker.com/content/dam/Parker-com/Literature/Brazil/Instrumentation/4220-Instrumentation-Quick-Couling---April-2008.pdf","accessed_at":"2026-10-30","access_status":"official historical PDF opened and readable; selected page screenshot requested","locator":"PDF/printed pages 31 and 35: series-specific mating profiles; page 46: coupling glossary; pages 47-48: selection and safety","excerpt":"Do not confuse burst pressure or other pressure values with rated pressure","supports_zh":"快换接头包含匹配的插头和插座；互换范围按系列/轮廓限定。选型需核对额定工作压力、介质与密封。2008年目录仅作结构和安全原则参考，不据此宣称当前供货或本站品牌互换。"}],"corpus_version":"2026-10-30.pneumatic-buying-guides.v1","corpus_sha256":"ea45a4ca2b449ccd1dd3c552729cc44972c43f124c3ea3955d769e706b9e0e25","hash_scope":"reviewed_editorial_corpus_file","scope":"General engineering guidance; not a certificate or specification for any listed product."} · Reviewed 2026-10-30

Only consider another medium when the exact component documentation permits it under the intended conditions. Check the body, seals, tubing and mating parts, including any relevant external cleaning exposure. Compatibility is a material-and-application question, not a conclusion from appearance. Provide the actual medium and service conditions with the inquiry and request a variant-specific assessment; an air-service description does not establish general fluid compatibility.

Source: SMC — Fittings and tubing precautions · {"source_ids":["smc-fitting-tubing-precautions","festo-media-resistance"],"sources":[{"id":"smc-fitting-tubing-precautions","publisher":"SMC","title":"Fittings and tubing precautions","url":"https://www.smcworld.com/upfiles/pl/recycle_bin/M-E03-3-10.pdf","accessed_at":"2026-10-30","access_status":"official PDF opened and readable; selected page screenshot requested","locator":"PDF page 2: Design/Selection and Mounting/Piping; PDF page 4, printed page 54: Maintenance and residual pressure","excerpt":"cut off the supply pressure and electric power","supports_zh":"该目录对适用介质、工作边界与维护作明确限制；拆卸前需防坠落/失控运动、隔离并排出残压。本文不把该目录的适用范围套给我方所有型号。"},{"id":"festo-media-resistance","publisher":"Festo","title":"Media resistance selection tool","url":"https://www.festo.com/us/en/s/media-resistance","accessed_at":"2026-10-30","access_status":"official explanatory HTML opened and readable; interactive compatibility calculation not run","locator":"Calculation / Media resistance, explanatory introduction","excerpt":"evaluate the resistance of different material types and tubing","supports_zh":"介质兼容性应针对材料和使用条件评估；工具介绍不能证明任意我方产品对某介质兼容，也未在本次运行具体化学兼容计算。"}],"corpus_version":"2026-10-30.pneumatic-buying-guides.v1","corpus_sha256":"ea45a4ca2b449ccd1dd3c552729cc44972c43f124c3ea3955d769e706b9e0e25","hash_scope":"reviewed_editorial_corpus_file","scope":"General engineering guidance; not a certificate or specification for any listed product."} · Reviewed 2026-10-30

Use the selected part's technical documentation and traceable identification instead of inferring ratings or material grade from its colour or finish. State your operating pressure, temperature and medium, then ask which documented variant is proposed. Working-pressure selection must not use a burst-pressure figure. If material documentation is required, request confirmation of its availability and its connection to the proposed part before purchase approval.

Source: Parker Hannifin — Quick coupling selection and safety guide · {"source_ids":["parker-quick-coupling-guide","festo-media-resistance"],"sources":[{"id":"parker-quick-coupling-guide","publisher":"Parker Hannifin","title":"Quick coupling selection and safety guide","url":"https://www.parker.com/content/dam/Parker-com/Literature/Brazil/Instrumentation/4220-Instrumentation-Quick-Couling---April-2008.pdf","accessed_at":"2026-10-30","access_status":"official historical PDF opened and readable; selected page screenshot requested","locator":"PDF/printed pages 31 and 35: series-specific mating profiles; page 46: coupling glossary; pages 47-48: selection and safety","excerpt":"Do not confuse burst pressure or other pressure values with rated pressure","supports_zh":"快换接头包含匹配的插头和插座；互换范围按系列/轮廓限定。选型需核对额定工作压力、介质与密封。2008年目录仅作结构和安全原则参考，不据此宣称当前供货或本站品牌互换。"},{"id":"festo-media-resistance","publisher":"Festo","title":"Media resistance selection tool","url":"https://www.festo.com/us/en/s/media-resistance","accessed_at":"2026-10-30","access_status":"official explanatory HTML opened and readable; interactive compatibility calculation not run","locator":"Calculation / Media resistance, explanatory introduction","excerpt":"evaluate the resistance of different material types and tubing","supports_zh":"介质兼容性应针对材料和使用条件评估；工具介绍不能证明任意我方产品对某介质兼容，也未在本次运行具体化学兼容计算。"}],"corpus_version":"2026-10-30.pneumatic-buying-guides.v1","corpus_sha256":"ea45a4ca2b449ccd1dd3c552729cc44972c43f124c3ea3955d769e706b9e0e25","hash_scope":"reviewed_editorial_corpus_file","scope":"General engineering guidance; not a certificate or specification for any listed product."} · Reviewed 2026-10-30

Provide the connection mechanism and shape, tube outside diameter and material, each port's full designation, intended medium and operating conditions. Include existing part references, photographs and a drawing revision where available. List any required technical or material documents, requested quantity and unresolved questions. Ask for an exact proposed part and a clear response to your requirements; documentation and commercial terms still need confirmation for that inquiry.

Source: Festo — Pneumatic fittings overview · {"source_ids":["festo-fitting-overview","smc-fitting-tubing-precautions"],"sources":[{"id":"festo-fitting-overview","publisher":"Festo","title":"Pneumatic fittings overview","url":"https://www.festo.com/us/en/c/products/connectors-fittings-tubings/pneumatic-connectors/pneumatic-fittings-id_pim315","accessed_at":"2026-10-30","access_status":"official HTML opened and readable","locator":"Pneumatic fittings; connection types and selection by tubing material and diameter","excerpt":"choose fittings that match your hose material and diameter","supports_zh":"气动连接存在多种结构，管材与尺寸是选型输入；可支持采购询问维度，不支持本站型号的具体兼容性。"},{"id":"smc-fitting-tubing-precautions","publisher":"SMC","title":"Fittings and tubing precautions","url":"https://www.smcworld.com/upfiles/pl/recycle_bin/M-E03-3-10.pdf","accessed_at":"2026-10-30","access_status":"official PDF opened and readable; selected page screenshot requested","locator":"PDF page 2: Design/Selection and Mounting/Piping; PDF page 4, printed page 54: Maintenance and residual pressure","excerpt":"cut off the supply pressure and electric power","supports_zh":"该目录对适用介质、工作边界与维护作明确限制；拆卸前需防坠落/失控运动、隔离并排出残压。本文不把该目录的适用范围套给我方所有型号。"}],"corpus_version":"2026-10-30.pneumatic-buying-guides.v1","corpus_sha256":"ea45a4ca2b449ccd1dd3c552729cc44972c43f124c3ea3955d769e706b9e0e25","hash_scope":"reviewed_editorial_corpus_file","scope":"General engineering guidance; not a certificate or specification for any listed product."} · Reviewed 2026-10-30

Have qualified personnel follow the machine's isolation and maintenance procedure, control unintended movement or falling loads, isolate relevant supplies and release stored pressure as instructed. Verify the safe condition before touching the connection. Use the selected component's assembly instructions and the required restart checks. A general FAQ cannot define every stored-energy location or replace the safety assessment for the particular machine.

Source: SMC — KE-series maintenance instructions · {"source_ids":["smc-ke-maintenance-manual","iso-4414-public-abstract"],"sources":[{"id":"smc-ke-maintenance-manual","publisher":"SMC","title":"KE-series maintenance instructions","url":"https://static.smc.eu/binaries/content/assets/smc_global/sistema/im_kq-smw58en.pdf","accessed_at":"2026-10-30","access_status":"official PDF opened and readable","locator":"KQ-SMW58EN, page 1, section 6.1 General Maintenance","excerpt":"Maintenance of pneumatic systems should be performed only by qualified personnel","supports_zh":"该型号维护章节要求合格人员、隔离电源/气源、确认空气排至大气以及维护后功能/泄漏检查；文章仅借此说明维护核对维度，不推定本站有该阀或复制型号额定参数。"},{"id":"iso-4414-public-abstract","publisher":"ISO","title":"ISO 4414:2010 public abstract","url":"https://www.iso.org/standard/44790.html","accessed_at":"2026-10-30","access_status":"official public abstract opened and readable; full paid standard not accessed","locator":"Abstract: machinery pneumatic systems, significant hazards and intended use","excerpt":"general rules and safety requirements for pneumatic fluid power systems","supports_zh":"ISO 4414涉及机器用气动系统及部件的安全原则；引用摘要不等于产品获ISO认证，也不支持根据摘要编写完整隔离操作规程。"}],"corpus_version":"2026-10-30.pneumatic-buying-guides.v1","corpus_sha256":"ea45a4ca2b449ccd1dd3c552729cc44972c43f124c3ea3955d769e706b9e0e25","hash_scope":"reviewed_editorial_corpus_file","scope":"General engineering guidance; not a certificate or specification for any listed product."} · Reviewed 2026-10-30