Service Scheduling

SERVICE SCHEDULING

BRUSH Aftermarket Support services are fully equipped to provide all existing operators with a comprehensive, standard or bespoke support package, that may be adapted to suit each and every individual operator’s need, wherever the installation be situated.

Regular maintenance

The notion that "prevention is better than cure" lies at the heart of any maintenance programme. Regular maintenance may be categorised into the following terms:

  • Preventative maintenance utilising regular inspection packages and the holding of strategic stock of parts.
  • Predictive maintenance utilising specific maintenance based on regular inspections and assessments of equipment condition and replacement material requirements.
  • Life-cycle maintenance utilising maintained stock of parts and exchange of strategic parts.
Recommended servicing for BRUSH DAX 2 pole generators

Service Interval 
(whichever occurs first)

Item

Procedure

Running Hours

Time Period (Months)

Number of Starts

2000

3

.

Enclosure Seals

Look for water or dust leaks. Seal as necessary. Replace seals as required.

2000

3

.

Oil Pump Gear Type Coupling

Inject approximately 0.01 - 0.015kg of fresh Shell Retinax HDX2 grease into the coupling. Do not overfill the coupling sleeve.

2000

3

.

Oil

Check oil level and top up as required.

2000

3

.

Rotor Earth Fault Monitor (REFM)

Press test button to test monitor.

4000

6

.

Oil Pipes & Flanges

Joints & Gaskets

Inspect for leaks. When the opportunity arises, attention should be given to joints that are hidden i.e. within bedplates.

4000

6

.

Earthing/Grounding Brush

Inspect. Brush must be free in holder. Replace when worn down to 14mm long with genuine BRUSH replacement brush.

4000

6

.

Lube Oil Sample

Examine for oil contaminants: water, acidity and general condition in conjunction with local oil supply agent. Replace if oil does not meet original specification and/or is not in accordance with local oil supply agent's recommendations.

4000

6

.

Air Inlet Seals

Check seals and ensure that no oil or dirt is penetrating the machine enclosure.

4000

6

.

Bearing Oil Seals

Check that bearing oil seals are not leaking.

4000

6

.

Door hinges, locks & catches

Apply drops of oil to ensure proper operation. Use dry graphite lubricant on cylinder locks.

4000

6

.

Inlet Air Filter

Inspect and replace with genuine BRUSH replacement filters when the differential pressure switch indicates increased pressure drop.

4000

6

.

Air Make-Up Filter

Inspect and replace and replace filter as necessary.

8000

12

.

Oil Filter

Replace with genuine BRUSH replacement filter element every 12 months or when the pressure switch or transmitter indicates increased differential pressure, whichever occurs first.

8000

12

.

Bearing Insulation

Check resistance.

8000

12

.

Blow Open Shutters

Stainless steel shutters have nylon bearings, lubrication is not required but check that they operate correctly.

8000

12

.

Protection Devices

Check mechanical and electrical protective devices to supplier’s specifications/manual settings.

8000

12

.

Electrostatic Precipitator

Check operation by absence of oil vapour in discharge during normal running of generator.

8000

12

.

Jacking Oil

Measure shaft lift adjacent to each bearing to verify operation of jacking oil system.

10000

18

.

Oil Pump Gear Type Coupling

The coupling must be dismantled and the grease completely replaced. If excessive gear mesh wear is evident complete coupling must be replaced. During assembly the coupling must be lubricated with grease Typically approximately 0.12kg of Shell Retinax HDX2). The external teeth of both hubs must be well coated with grease and a small amount applied to the rubber sealing rings. The remainder of the grease should be applied to the internal teeth at both ends of the coupling sleeve and smoothed around the inside of the sleeve. Care must be taken not to overfill the coupling with grease since this may cause leakage from the seals.

16000

24

.

Paint work

Check paintwork to ensure that it is in good condition. If it has become damaged then the affected areas should be repainted.

25,000

50*

.

Knife Edge Seals

Check air pipes for signs of deterioration. Replace if necessary.

25,000

50*

.

Pressurised Seals

Check that air gap pressure at intermediate seal compartments is higher than in main bearing housing. If it is not, check air pipes and seal clearance.

25,000

50*

2,500

Main Exciter

Rectifier Assembly

Remove any accumulated dust from the rotating rectifiers and the main exciter. Check electrical connections are secure. Verify integrity of armature end winding banding.

25,000

50*

.

Rotor End Windings

Remove excess deposits using vacuum cleaner, small bottle-brushes and dry, lint-free rags to achieve a uniform state on both sides of a diameter. CAUTION: Avoid moving contaminants further into the windings.

25,000

50*

.

Stator End Winding

Inspect and remove excess deposits of dust and grease. Use vacuum cleaner, brushes and lint-free cloth. If the dirt proves to be stubborn, wipe sparingly with `Pro Natur' Orange Oil) or equivalent. CAUTION: Avoid washing contaminants further into the windings.

40,000

60*

5,000

Main Bearings

Bearing Check - remove bushes. Examine for pressure concentration, scoring and drag marks. Damaged areas may be carefully scraped, taking care not to destroy bearing profile. Check bearing top clearance at each end of the bush by means of lead strips. Check bearing side clearances with feeler gauges.

Note: Hoses, along with other pipework and associated connectors, should be inspected for signs of deterioration during bush removal/reassembly and replaced as necessary.

100,000

12½ years

10,000

Complete Machine

Review with manufacturer for recommendations for full inspection/overhaul.

100,000

12½ years

10,000

Rotor End Caps

Perform non-destructive testing. Check for cracks on surfaces of rings, remove if necessary.

The schedule provided is an overview of the different kinds of condition inspections that are recommended to be carried out during inspection rounds.

The mentioned intervals are an indication only, and can be adjusted according to the maintenance rounds of the turbine, actual service duty and local circumstances

Recommended servicing for BRUSH DG 4 pole generators

Service Interval 
(whichever occurs first)

Item

Procedure

Running Hours (min)

Time Period

Number of Starts

24

Daily (2)

.

Electrical maintenance periods

Replacement of brushes

24

Daily

.

Others

General external visual inspection: look at, listen to and feel the machine

24

Daily

.

Lubrication system

Lubrication piping (leakage, operation)

24

Daily

.

Lubrication system

Lubrication oil (quality, quantity, flow)

24

Daily

.

Lubrication system

Oil ring/ flow regulator (operation)

24

Daily

.

Lubrication system

Oil tank (Cleanliness, leakage)

24

Daily

.

Electrical maintenance periods

Check/logging load conditions (kV, 3xAmps, kW, kVA, power factor, Hz)

24

Daily

.

Electrical maintenance periods

Check/logging excitation volts / amps

24

Daily

.

Electrical maintenance periods

Winding temperature check/logging

24

Daily

.

Electrical maintenance periods

Oil pumps and equipment

24

Daily

.

Cooling system maintenance

Cooling system temperature checks/loggings

24

Daily

.

Cooling system maintenance

Check pressure drop across air inlet filters (if applicable)

24

Daily

.

Bearings

Metal temperature check/logging

4000

6 months (3)

.

Lubrication system

Re-lubrication / Oil change

35000

4 years(1)

.

Electrical maintenance periods

Insulation Resistance measurements/ Anti-condensation heaters good operation

35000

4 years

.

Others

Check Spare Parts (general conditions, availability)

35000

4 years

.

Others

Jacking oil system (operation)

35000

4 years

.

Electrical maintenance periods

Polarization Index test (stator)

35000*

4 years

.

Electrical maintenance periods

Dielectric Loss Factor measurements (tan delta)

35000*

4 years

.

Electrical maintenance periods

Partial discharge analysis

35000

4 years

.

Electrical maintenance periods

Winding resistance measurements (stator, rotor, exciter, exc. field)

35000

4 years

.

Electrical maintenance periods

Cleaning/Inspection of stator (MV) - Windings

35000

4 years

.

Electrical maintenance periods

Cleaning/Inspection of rotor, exciter windings, diodes and fuses

35000

4 years

.

Electrical maintenance periods

Inspection/Cleaning of slip rings (wear, roundness, patina), brush gear (arching, clearance)

35000

4 years

.

Electrical maintenance periods

Inspection of brush holders (alignment)

35000

4 years

.

Electrical maintenance periods

Brushes conduction resistance measurements

35000

4 years

.

Electrical maintenance periods

Carbon brushes check

35000

4 years

.

Electrical maintenance periods

Inspection Terminal Boxes (Insulators, Neutral Earthing Resistors, Measuring Transformers, Connections etc.)

35000

4 years

.

Cooling system maintenance

Inspection of Air Inlet Filters (if applicable)

35000

4 years

.

Cooling system maintenance

Check on Water Leakages/Detectors (if applicable)

35000

4 years

.

Cooling system maintenance

Inspection of the Cooling Fans and motors

35000

4 years

.

Cooling system maintenance

Cleaning of the air guiding shields

35000

4 years

.

Cooling system maintenance

Water flow regulator (operation)

35000

4 years

.

Cooling system maintenance

Seals and gaskets (leakage, conditions)

35000

4 years

.

Bearings

Cleaning/Inspection Bearings, Bearing Houses, Journals, Clearance measurement

35000

4 years

.

Bearings

Seals and gaskets (leakage)

35000

4 years

.

Bearings

Dye check of Babbitt bonding

35000

4 years

.

Bearings

Check vibration level history and perform frequency analysis on existing data, if required

35000

4 years

.

Bearings

Check bearing instrumentation

100000

12 years

.

Stator

Whole structure (general conditions, visual inspection for oil leaks, rust patches or other defects)

100000

12 years

.

Stator

Core (fixing, cracks, welds)

100000

12 years

.

Stator

Slot wedges (movement, tightness)

100000

12 years

.

Stator

Terminal bars (fixing)

100000

12 years

.

Stator

Windings (general conditions, connections, insulation, tightness of bracing and tying material)

100000

12 years

.

Stator

Cable terminal fastenings and crimps (tightness, general conditions)

100000

12 years

.

Rotor

Remove, clean and inspect rotor

100000

12 years

.

Rotor

Poles (movement, tightness, fixing)

100000

12 years

.

Rotor

Coil supports (movement, bending)

100000

12 years

.

Rotor

Balancing weights (movement)

100000

12 years

.

Rotor

Shaft and rotor centre (crack, corrosion)

100000

12 years

.

Rotor

Air gap (equality)

100000

12 years

.

Rotor

Application of varnish layer

100000

12 years

.

Rotor

Balance Check

100000

12 years

.

Others

Alignment

100000

12 years

.

Others

Inspection Bolted Connections (tightness of all fastenings)

100000

12 years

.

Others

Inspection Machine housing (rust, leakage, general conditions)

100000

12 years

.

Cooling system maintenance

Inspection of the Cooling Circuit (flanges, tubes, etc.) (if applicable)

100000

12 years

.

Cooling system maintenance

Cleaning of the Air Cooler Pipes (if applicable)

100000

12 years

.

Cooling system maintenance

Pressure Test (Water Cooler)

(4)

(4)

.

Control and Protection equipment

Confirm generator breaker and HV line are tested

(4)

(4)

.

Control and Protection equipment

Functional test protection system

(4)

(4)

.

Control and Protection equipment

Confirm generator protection system is in good working operation

(4)

(4)

.

Control and Protection equipment

Confirm AVR is in good working conditions

The schedule provided is an overview of the different kinds of condition inspections that are recommended to be carried out during inspection rounds.

The mentioned intervals are an indication only, and can be adjusted according to the maintenance rounds of the turbine, actual service duty and local circumstances.

Schedule notes:

  1. Insulation resistances of stator windings, rotor winding, exciter windings, exciter field winding, brush gear, slip-rings, diode wheel (diodes to be short-circuited), heaters, temperature detectors, insulation of bearings should be measured.
  2. To avoid any risks for damages, brushes should be replaced at the moment the original brush length has been reduced to approximately 35% of original length.
  3. The oil change interval is dependent on the condition of the oil. BRUSH advises samples to be taken every 6 months.
  4. According to manufacturer's manual.