1. Fans & Heaters technical seminar
Howden APH field services
Henry Castro

2. Improve Your Plant Reliability and Availability1
Introduction to Howden field services 2
Air Pre-heater description 3
Air Pre-heater operation and maintenance 4
Air Pre-heater retrofit works 5
Best practice 6
What is next? Challenge Howden

3. Introduction to Howden Field Services
Responsibilities and contributions
Provide technical support to the day to day needs of plant personnel for the optimum operation and adequate maintenance of their equipment
Provide guidance in programming of activities and supervision of works on air heaters maintenance
Help with the implementation of industry proven improvements and best practices which are suitable to individual clients need
Assure on site health and safety policy: Howden developed a Heater Rotation Procedure which emphasizes the personnel safety inside the APH

4. Air Pre-heater description

5. APH description Typical power plant schematic Air Preheater
Gas-Gas Heater

6. APH description Rotating matrix (LJUNGSTROM)
Rotating and stationary matrix APH
Rotating matrix (LJUNGSTROM)
Stationary matrix (ROTHEMUHLE)
Typical Rotating Matrix Air Preheater
Typical Stationary Matrix Air Preheater

7. Top Connecting Flanges Bottom Connecting Flanges
APH Description
Rotating Matrix Major Components
Radial Seals
Top Drive Unit
Rotor
Heating Elements
Top Access Door
Rotor Casing
Guide Bearing
Top Connecting Flanges
End Pillars
Axial Sealing
Bottom Connecting Flanges
Bottom Access Door
Circumferential Seals

8. APH Description Commonly known as ROTHEMULHE
Stationary Matrix Major Components
Commonly known as ROTHEMULHE

9. APH operation and maintenance

10. APH operation and maintenance
Operation checklist
Typical operation checklist on Air Heater
Temperatures
Check that the incoming and outgoing air and gas temperatures are within the design values
Check the Combined Cold End Temperature (CCET) is within the minimum required value
Check the soot blower steam (if applicable) temperature is within the minimum required value
Check the bearings and drive unit lube oil temperature are within the permitted level
Pressures
Check that the incoming and outgoing air and gas pressures are within the design values
Check that the differential pressures across the equipment are within the permitted level.
Others
Check for the air leakage by monitoring the O2 and/or CO2 level upstream and downstream of the equipment
Check for rotor seals rubbing, especially after replacement of seals
Check for air/gas leakage on shaft packings
Check for oil level on bearings and drive unit gear boxes.

11. APH operation and maintenance
Maintenance checklist
Typical list of maintenance work on Air Heater
Replacement of Heating Element
Replacement of rotor seals
Overhauling of the soot blowers
Overhauling or replacement of rotor support and guide bearing
Overhauling or replacement of the drive unit
General repair works on rotor, housing, and transition ducts
Repair or replacement of the sector plates
Repair or replacement of the sector plate static seals
Repair or replacement of the axial plates
Repair or replacement of the expansion joints
Dry test of the fire protection and detection system

12. Basket replacement

13. Replacement of cold end baskets from the lateral side of the rotor
Basket replacement
Vertical shaft heater
Replacement of cold end baskets from the lateral side of the rotor
Replacement of hot and intermediate baskets from the upper end of the rotor

14. Basket replacement
Horizontal shaft APH
Replacement of hot and intermediate end baskets from the lateral side
Replacement of sector baskets from the top end side of the APH

15. Horizontal shaft APHs
Points to consider
It must lock the rotor every time it is at a rest position to avoid possibility of movement due to imbalance. It is also recommended to install a provisional locking device in addition to the brake in the drive unit for additional safety measure.
Replacement of the baskets should be done in a sequence where rotor imbalance is minimized to one sector.
Rotor balancing should be conducted after completion of baskets replacement.
Drive unit equipped with break assembly
Rotor Additional Blocking

16. Horizontal APH Installation of balancing plates
Balancing plates welded on the rotor shell after completion of baskets replacement

17. Seals replacement

18. Seals replacement
Wireless seal plates levelness measuring device
Howden developed a unique wireless laser measuring tool for a very precise measurement of the sealing plates, which results in an accurate and efficient setting of the rotor seals.

19. Seals replacement
Radial seals

20. Outer circumferential seals
Seals replacement
Outer circumferential seals
Replacement of Lower Outer Circumferential Seals
Replacement of Upper Outer Circumferential Seals

21. Inner circumferential seals
Seals replacement
Inner circumferential seals
Replacement of upper inner circumferential seals
Replacement of lower inner circumferential seals

22. Seals replacement
Axial seals

23. Seals setting chart and rotor reformation
Seals replacement
Seals setting chart and rotor reformation

24. APH retrofit works

25. Complete rotor replacement and conversion to double sealing
APH retrofit works
Complete rotor replacement and conversion to double sealing

26. APH retrofit works
Replacement of the rotor bottom section and installation of new heating elements

27. APH retrofit works
Complete replacement of the cold end side of a GGH for corrosion Issues

28. Replacement of the rotor due to fire incidence
APH retrofit works
Replacement of the rotor due to fire incidence

29. Installation of new jet blowers
APH retrofit works
Installation of new jet blowers

30. Installation of new fire detection and extinction system
APH retrofit works
Installation of new fire detection and extinction system

31. Best practice

32. Best practice
For optimum sealing, verify the actual combined deformation of the rotor and the stationary components at unit full load. Set the rotor seals against these values.
Always verify soot blowing steam quality, ascertain that pressure and temperature are within the recommended values and that the condensate drains are functioning well.
Use health checks as preventive maintenance where comprehensive inspection reports are submitted and discussed with plant personnel.
Ask for support from Howden experienced personnel. Our Service Technical Advisors have worked in more than 100 plants in 30 different country all over the world.

33. What can Howden do for you next?
What next?
Challenge Howden
What can Howden do for you next?
Outage Planning?
Product Training?
Spare Parts Audit?
Maintenance Planning and Advice?
Product Performance Analysis?
Challenge Howden

34. Our experience at your service Thank you for your time