When specifying oxygen manifold pigtails and cylinder connections, procurement teams often face ambiguity because the connection assembly involves two distinct interfaces: the manifold side and the cylinder side. The connecting assembly links the cylinder valve to the manifold cylinder-bank inlet. This article explains how to define both ends clearly in your RFQ, separate from cylinder valve ordering, and what to request from suppliers to ensure a precise quotation.

The Two Ends of a Pigtail

A pigtail has two connection points. One end attaches to the manifold cylinder-bank inlet; the other attaches to the cylinder valve. Each end requires a defined connection type, size, and standard. In an RFQ, state both ends explicitly. For example, specify the manifold-end thread and the cylinder-end thread, along with any required adapters. If the cylinder valve is ordered separately, ensure the pigtail cylinder-end matches the valve outlet. This avoids mismatches and rework.

Connection Identification and Gas Service

Connection identifiers vary by region and standard. Provide the exact connector designation and drawing reference for each end, as confirmed by the responsible technical team. State oxygen as the intended gas service on each relevant order line. Material compatibility and cleaning requirements depend on the gas. Ask the responsible engineer to specify the oxygen-service material and cleanliness requirements, then request supporting documents for the offered assembly. Do not assume that a standard connection implies suitability for a particular gas; confirm with the supplier.

Length, Quantity, and Supply Scope

Pigtail length affects flexibility and routing. Specify the required length from end to end, and whether a tolerance is acceptable. Quantity should be stated as the total number of assemblies, with any spare units. Clarify whether the supply includes protective caps, labels, or test certificates. If the manifold requires a specific number of pigtails, state that number and whether the pigtails are supplied as a set or individually.

Documentation and Verification

Request original manufacturer documentation for the pigtails and connections. This may include material certificates, pressure test reports, and cleaning certificates. Verify that the documentation matches the ordered specifications. If the supplier provides a drawing, check that both ends and the length are correctly depicted. For project teams, the qualified engineers should review and approve technical requirements before ordering.

Comparison Schedule for RFQ Clarity

Use this fillable schedule to capture key details for each pigtail assembly. Complete it with your project data and share it with suppliers.

Add rows as needed. Include gas service and quantity in the RFQ text. This schedule helps suppliers quote accurately and reduces back-and-forth.

Questions to Ask Suppliers

• What are the exact thread specifications for each end?

• Are the connections compatible with our cylinder valves? (Provide valve details.)

• What materials are used for the pigtail tubing and fittings?

• What cleaning process is used for oxygen service?

• What documentation is provided with each assembly?

• What is the lead time for the specified quantity?

• Are spare parts or adapters available?

Manifold Connection Enquiries

We are Kersai Medical, based in Qingdao, China, and our catalogue includes manual medical gas manifolds. To discuss your project, please share the gas service, existing cylinder connection details, and project scope with our team via the contact page. For manifold specifications, visit our manual manifold for medical gases page. If you are also ordering cylinder valves, refer to our oxygen cylinder valve ordering checklist to keep the two lists separate and complete.