Moving Grate

Breiding is independent – we supply spare parts to OEM’s as well as end customers. Thus we know the different systems and the spare parts in use. From Breiding you can expect OEM quality (or better) by lower prices. As our engineers are inspecting between 3 and 10 grates each week, we have seen plenty of problems. Our impression is that:

  • Many customers feel left alone after completion of the plant.
  • Some don‘t have complete documentations of their plant.
  • Solutions are mostly: „One grate bar fits all“
  • Standard solutions lead to standard performance – or less.

From the many different individual plant problems we have developed a thorough understanding of cause and effects. We have seen interactions caused by grate design changes which lead to a completely unexpected new wear pattern or deteriorated combustion.

The grate is the heart of the boiler. A homogenous fire leads to

  • better emission values,
  • less suspended particles in the flue gas,
  • less cornice formation at the brick walls
  • and less damages to the tube systems in the superheater.

In the recent years we have developed new grate bars for a number of OEM’s – due to the focus on grate enhancements Breiding is known to have more experience in enhancements than the OEM’s themselves. Why?
We can transfer our know how from changes at one system to other systems from different OEM’s. We have seen and fixed problems, – we have seen what worked – and sometimes what did not work.

Grate bar portfolio – standard or customized? Small enhancements – huge impact

According to the customer´s individual wear patterns, our design team optimizes grate bars.

Shape adjustments

  • Extended life time through optimizations to prevent the occurrence of abrasion, erosion and corrosion
  • Design changes improve heat transfer:
    • T-shaped grate bar
    • U-shaped grate bar
    • Honeycomb pattern cooling grid structure
  • Potential areas of weaknesses are strengthened, e.g. head, foot and back
  • We generate savings in unit costs – e.g. doubled width leads (compared to two single grate bars) to a decrease of weight/cast iron needed for the casting process.

Air flow system adjustments

  • Air flow systems are adapted to fuel characteristics in order to increase the efficiency of the incineration and the durability of each bar.

Alternatives to screws and connection rods

  • Patented claws connect grate bars to each other.
  • Grate bars cannot lift out of line.
  • No displacement of individual grate bars out of the normal working position – no jamming of entire grate steps by lifts of individual grate bars.
  • Easy assembly! Bundling by connection rods becomes redundant.
  • Air gaps are constantly fixed and kept open – a homogenous fire is established.

Labyrinth seal

  • The patented labyrinth seal is for furnaces with very fine fuel.
  • The overlap prevents from uprising bars.
  • It minimizes ash leakages through the grate.
  • No air passes the overlap – no torch fire effect!

Material variations

  • Changes in the portion of nickel and/or chrome enhance the service life of wear parts.

Torch fire effects destroy grate bars as nozzles burn out. Ceramic is the solution!

Our research to increase the durability of grate bars has lead us to the idea of matching two efficiently proven materials (which usually exclude each other!): ceramic and heat resistant cast iron within one wear part!

The Problem: Nozzles are urged with ash, slag and fuel. The remaining active nozzles experience increasing air volumes passing through. This leads to high air speed and increasing temperatures: the feared forge-fire-effect takes place. The primary air cannot pass the nozzles in a controlled manner – the grate bars are rendered unusable within a short time. Nozzles burn wide open.

Result: Unscheduled downtimes and short frequencies of grate replacements.

Our goal: Unscheduled downtimes and short frequen-forge-fire-effect needs to be increased!

Our Solution: the ICeramiGX® !

Why ICeramiGX®? It’s a symbiosis! The molded ceramic eliminates the specific weak point of the grate bars. The ceramic nozzle can resist up to 1,800° Celsius! The burnout of the nozzles is avoided!

The ICeramiGX® is a suitable alternative to water-cooled grate bars as well!

The ICeramiGX® is a resistant and – compared to other systems – cost-effective alternative to water-cooled grate bars. Complex and fault-prone equipment can be dispended. We accompany your deconstruction – either zones or complete grates – to air cooled systems using the ICeramiGX®.

A flexible, modular grate bar adapted to the individual needs of the grate.

Each combustion chamber has its own unique wear pattern and thus different needs. These characteristics have a high impact on the efficiency of the combustion and the lifetime of the grate.

Plant-specific wear patterns depend on the fuel, the boiler configuration and the facility utilization.

There is no solution “one grate bat fits all”. Standard solutions lead to standard performance – or less.

Customized solutions are inevitable.

Our approach

  • We analyze the individual situation of the grate.
  • We look for recurrent (wear) patterns.
  • We discover the potential areas of concern.
  • The new design is adapted to the customer’s individual needs and consists of multiple single components.

Conventionally operated grate bars had to be replaced as soon as one area of the bar was worn out. Now, only the given area is replaced and the rest of the bar can still be reused.

Your advantages

  • You receive a flexible, modular grate bar.
  • The grate bar is adapted to your individual needs.
  • You only order the components that have to be replaced. Thus, the purchasing budget can be reduced by up to 80%.
  • The components can be casted in different materials. It is possible to strengthen weak points by using more resistant alloys and save budget on components where higher alloys are not needed.