Filter House Performance Assessment Saves Full Set of Filters

A Midwestern peaking facility had changed filters less than 18 months earlier only to see progressive turbine output degradation. The Plant Manager of the facility contacted Nederman MikroPul to discuss the issue and agreed upon a plan to have a Certified Nederman Field Technician perform a field inspection to help identify any issues that could be contributing to the problem.

Tripod and gasket repairs addressed the bypass condition in all four systems along with recommended repairs to weather hoods and door gaskets.

Every Nederman Mikropul Field Services Technician goes through extensive design and equipment training and is certified for services on all styles of air inlet systems. After issues with improper tripod orientation and damaged gaskets were revealed it was recommended that several sets of filters be sent to an independent lab for testing. Once the gasket had been properly replaced and secured, the filters were confirmed to be in good shape. Nederman was contracted to perform the repairs and properly install filters that allowed all four systems to be up and available before the start of their running season.

Outages are the perfect time to assess maintenance needs and reduce unforeseen and expensive discovery down the road. Photographs along with comprehensive reports allow a full and complete understanding of the maintenance needs and to better prepare budgets and execution of work during future outages.

Below are typical assessment work scopes

Inspection Scope – Self-Cleaning (Pulse) Filter House

Inspection Summary – Dirty Air Side – Self-Cleaning Filter House
Item #	Report Section	Item’s Covered
1	Exterior Housing	Housing, weld seams, expansion joint,
2	Exterior Weather Hoods	Metal, seams, joints, bird screen, coalescing panels
3	Compressed Air Piping
4	Ladder/Stairs/Platform	Signs of corrosion, warpage, cracks
5	External Access Doors	Signs of corrosion, debris build up
6	Panel/gauges	Condition of lenses, housings,
7	Access to Dirty Air Plenum	Exterior of access door, signs of corrosion or warpage
8	Interior Access Door	Signs of corrosion, condition of door seals
9	Condition of Dirty Air Walkway	Corrosion, cracks debris buildup, signs of moisture
10	Supports, angles, beams	Corrosion, cracks, connections, joints
11	Horizontal Recognition	Check level and orientation of filters with lazor
12	Connecting Hardware	Corrosion, consistency of orientation to bolt
13	Gasket Compression	“go” “ no-go” gauge
14	Condition of tubesheet	Corrosion, debris buildup, warpage, seams, joints
15	Solenoid Boxes	Check for proper seal in panel, corrosion, wiring
16	Solenoids	Check wire and hose connection
17	Compressed Air Hoses	Check for flexibility, fit
18	Interior Weather Hood	Check alignment of  bird screens, droplet/mist panels
19	Pressure Tap	Inspect penetration of DP piping

Inspection Summary – Clean Air Side – Self-Cleaning Filter house
Item #	Report Section	Item’s Covered
1	Filter Grid	Signs of moisture, Debris settling, gasket Seal
2	Filter Grid	Dark Side – Light detection
3	Compressed Air Piping	Inspect penetrations for pulse systems
4	Structural	Signs of corrosion, warpage, cracks, condition of paint
5	Access Doors/portals	Signs of corrosion, leaks
6	Control lines/Tubes	Condition of lenses, tube connections
7	Drainage Trough	Inspect for debris and standing moisture
8	Air Augmentation	Evaporative Cooling Media, Basin, Piping, Valve, Pump, Distribution Header, Droplet eliminators
9	Interior Plenum	Inspect walls and floor for corrosion, cracks, connections, joints
10	Silencer	Inspection of leading edge of silencer baffles
11	nterior – Expansion Joint	Inspect for cracking, leaks, light
12	Report	Generate report on findings

Inspection Summary – Dirty Air Side Static House

Inspection Summary – Dirty Air Side Static House
Item #	Report Section	Item’s Covered
1	Exterior Housing	Housing, weld seams, expansion joint
2	Exterior Weather Hoods	Metal, seams, joints, bird screen, coalescing panels
3	Horizontal Hood Section	Inspect Droplet Eliminators and or Bird Screen
4	Ladder/Stairs/Platform	Signs of corrosion, warpage, cracks
5	External Access Doors	Signs of corrosion, debris build up
6	Monitoring Tube/Pipe	Inspect penetration and orientation
7	Access to Dirty Air Plenum	Exterior of access door, signs of corrosion or warpage
8	Interior Access Door	Signs of corrosion, condition of door seals
9	Condition of Dirty Air Walkway	Corrosion, cracks debris buildup, signs of moisture
10	Supports, angles, beams	Corrosion, cracks, connections, joints
11	Horizontal Recognition	Check level and orientation of filters
12	Connecting Hardware	Corrosion, consistency of orientation to bolt
13	Gasket Compression	Check for seal
14	Condition of tubesheet	Corrosion, debris  buildup, warpage, seams, joints
15	External Control Boxes	Confirm operation
16	External Gauges	Check if indications on gauge are visible
17	Air Hoses and tubes	Check fit

Inspection Summary – Clean Air Side – Static Filter house
Item #	Report Section	Item’s Covered
1	Filter Grid	Signs of moisture, Debris settling, Gasket seal
2	Filter Grid	Dark Side – Light detection
3	Structural	Signs of corrosion, warpage, cracks, condition of paint
4	Access Doors/portals	Signs of corrosion, leaks
5	Control lines/Tubes	Condition of lenses, tube connections
6	Drainage Trough	Inspect for debris and standing moisture
7	Air Augmentation	Evaporative Cooling Media, Basin, Piping, Valve, Pump, Distribution Header, Droplet eliminators
8	Interior Plenum	Inspect walls and floor for corrosion, cracks, connections, joints
9	Silencer	Inspection of leading edge of silencer baffles
10	Interior – Expansion Joint	Inspect for cracking, leaks, light
11	Report	Generate report on findings