Economisers
The economiser (ECO, feedwater preheater) uses the residual heat of the flue gas to heat the feedwater before it enters the evaporator. We supply economiser packages to your drawing – coils of bare or finned tube with inlet and outlet headers, welded, tested and documented. ROHRLINE, based in Grafenwörth (Lower Austria), supplies Economisers to drawing – tested, with 3.1 or 3.2 certificates to EN 10204 – worldwide.
Scope of supply & execution
| Item | Detail |
|---|---|
| Basis of manufacture | Drawing, parts list or survey of the existing package |
| Tube type | Bare tube, spirally finned or H-finned tube to drawing |
| Tube size | Outside diameter 25 to 60.3 mm, wall thickness as designed |
| Headers | Inlet and outlet headers with nozzles, vent and drain to drawing |
| Materials | P235GH, P265GH, 16Mo3; stainless grades for condensing flue gases |
| Code | EN 12952 or EN 12953, Pressure Equipment Directive 2014/68/EU |
| Testing | Visual inspection, NDT of the butt welds, pressure test with report, ball passage test |
| Documentation | 3.1 or 3.2 certificate to EN 10204, test reports, weld map |
Materials we supply for this
The grade follows from medium, temperature and pressure. The list below is a selection, not a limitation – we supply the grade that design and specification call for. Each grade has a data sheet with composition, properties and standards.
Typical fields of use
- Feedwater preheating in steam and hot-water boilers
- Heat recovery boilers downstream of gas turbines and engines
- Waste incineration and biomass plants
- Replacement of complete packages during outages or after corrosion damage
- Flue gas heat exchangers and condensing heat recovery
The records you receive
Inspection certificate 3.1 or 3.2 to EN 10204
Batch-related test results for every pressure-bearing item, countersigned on request.
Non-destructive testing
Visual, penetrant, magnetic particle, ultrasonic or radiographic testing of the welds as specified.
Pressure test
Hydrostatic test to the applicable code and drawing, with test report.
Traceability
Batch and heat number of every item remain traceable through the documentation.
From drawing to delivery
1. Drawing or sketch
Send us the drawing, isometric or bill of material – a hand sketch with dimensions is enough to start.
2. Agree material and code
We settle grade, standard, pressure rating and the required certificate with you.
3. Quotation
You receive a quotation with price, execution and a firm delivery date.
4. Delivery with documentation
The component arrives ready to install, with certificates and test reports.
Economisers – frequently asked questions
What is an economiser?
The economiser is a heat exchanger in the flue gas path of the boiler that preheats the feedwater with the residual heat of the flue gas before it reaches the evaporator. This lowers the flue gas temperature and raises boiler efficiency. ROHRLINE supplies economiser packages to drawing with a certificate to EN 10204.
Bare tube or finned tube?
Finned tubes enlarge the heating surface on the flue gas side and make the package more compact; they suit clean flue gases, for example from natural gas. With dusty or fouling flue gases, as in waste incineration and biomass, bare tube is usually the better choice because it is easier to clean.
Can you supply a replacement for an existing economiser?
Yes. The basis is the original drawing or, if it is missing, a survey of the existing package with tube pitch, number of coils and header connections. We check material and wall thickness against the original design before ordering.
What do you need for a quotation?
Drawing or survey, tube size and material, tube type, number of coils, design pressure and temperature and the required certificate to EN 10204. A dimensioned sketch is enough for a first calculation.
Send your drawing – we will clarify the rest together
A drawing, bill of materials or short description is enough to get started. If already available, the following details help us prepare your quotation quickly.
- Drawing of the package or survey of the existing economiser
- Tube size, material and tube type (bare, spirally finned, H-finned)
- Number of coils, run lengths and header connections
- Design pressure and temperature
- Certificate 3.1 or 3.2, required date and delivery address
Economisers – request a quote
Drawing, material and quantity are enough – we come back with price and lead time.