An injection quill introduces a chemical into a process pipeline at a defined insertion point. A complete request for quotation helps the supplier review the quill arrangement, materials, connection, insertion length and isolation requirements against the actual service conditions.
This guide is for engineering teams, EPC contractors, skid builders, plant operators and procurement departments preparing an injection quill enquiry in India. Final selection should be based on the confirmed chemical and process data, piping arrangement and project specification.
What information does an injection quill supplier need?
The RFQ should describe both the injected chemical and the receiving process stream. Compatibility and mechanical design cannot be reviewed reliably from the chemical name alone.
- Injected chemical name and concentration
- Chemical flow rate at minimum, normal and maximum duty
- Chemical pressure and temperature
- Main process fluid, pressure, temperature and flow rate
- Line size, piping schedule and pipe material
- Nozzle or branch connection size and rating
- Required quill material and gasket requirements
- Project tag number and quantity
- Applicable project and client specifications
If the chemical can crystallise, polymerise, form deposits or attack common alloys, state this in the enquiry. The supplier should not have to infer compatibility from a trade name.
Fixed or retractable injection quill
A fixed injection quill is normally installed or removed when the line is safely isolated and depressurised. A retractable arrangement is intended for services where the project requires withdrawal without removing the complete process connection. The exact arrangement depends on the operating pressure, isolation method and site procedure.
The RFQ should not simply state retractable without defining the operating and maintenance requirement. Include the line pressure during withdrawal, the expected frequency of inspection, the available access space and the required isolation arrangement.
How to define insertion length
Insertion length affects where the chemical enters the process stream. To review it, provide the pipe outside diameter, wall thickness, nozzle projection, flange or threaded connection details and any internal lining. A marked piping sketch is often more useful than a nominal line size alone.
The proposed outlet position should also consider nearby elbows, reducers, valves, instruments and other fittings. If the project specification defines a preferred injection point, attach the relevant detail.
Outlet, nozzle and dispersion requirements
Injection quills can use different outlet arrangements depending on the dosing objective and process conditions. The requested arrangement may include a plain outlet, an angled tip, multiple openings or a separate nozzle concept. Do not specify an outlet pattern only from a reference photograph.
Explain the dosing objective and provide the chemical and process flow data. If atomisation, spray coverage or droplet size is required, state the acceptance criteria and whether a separate atomising medium is available. A chemical injection quill and a chemical atomiser are not automatically the same item.
Material selection information
Material selection should consider both sides of the quill. The wetted material must be reviewed against the injected chemical as well as the main process fluid. The RFQ should identify:
- Required body, tube and tip materials
- Flange or connection material
- Seal and gasket materials
- Corrosion allowance, if applicable
- Any sour-service or low-temperature requirement
- Required material certification
If the material is to be selected by the supplier, provide the complete service composition and the client’s approved material restrictions.
Check valve and isolation scope
A check valve may be used to reduce the risk of reverse flow into the chemical line. The RFQ should state whether it is integral to the quill, supplied separately or already included in the dosing system. Required isolation valves and fittings should also be listed clearly.
Do not assume that every injection quill quotation includes a check valve, isolation valve, mating flange, tube fitting or spray nozzle. Define the full supply boundary.
Documents and testing to request
Documentation requirements should match the project and service. The enquiry may request:
- General arrangement drawing with insertion dimensions
- Material certificates
- Pressure test records when applicable
- Inspection and test plan
- Welding and non-destructive examination records when applicable
- Installation, operation and maintenance instructions
- Tagging, nameplate and data book requirements
Injection quill RFQ checklist
- Identify the chemical, concentration and dosing rate.
- Provide chemical pressure and temperature.
- Provide main-line fluid, flow, pressure and temperature.
- State line size, schedule, material and internal lining.
- Attach the branch connection or nozzle detail.
- Define fixed or retractable construction.
- State the required insertion point and available clearance.
- Define materials, seals and applicable service restrictions.
- List check valve, isolation valve and fitting scope.
- State inspection, testing and document requirements.
Common enquiry mistakes
A frequent mistake is providing the dosing chemical data but omitting the main process conditions. Another is specifying only a nominal insertion length without the pipe schedule or nozzle projection. These gaps can produce an arrangement that does not place the outlet at the intended location.
Also avoid using injection quill, dosing quill, injection nozzle and chemical atomiser as interchangeable terms without explaining the required function. The correct product description follows from the service and performance requirement.
Frequently asked questions
What is the difference between a fixed and retractable injection quill?
A fixed quill is generally removed after the process connection has been isolated and depressurised. A retractable quill uses a withdrawal arrangement defined for the service and maintenance procedure. The project must state the conditions under which withdrawal is expected.
Is a check valve always included?
No. The required check valve, isolation valve and fitting scope should be stated in the RFQ. The quotation should identify what is included.
Can insertion length be selected from pipe size alone?
No. Pipe schedule, connection projection, lining and the desired outlet location also affect the required insertion length.
Prepare the enquiry for review
Review the IPS Automation injection quill page and send the completed service data, piping information and documentation requirements through the contact page. Clear inputs help reduce clarification time and support a more useful technical quotation.