Flue gas duct / components

Compensators are an essential component for flue gas ducts, especially at high temperatures. They are used to compensate for length changes caused by temperature fluctuations. Additionally, they are capable of absorbing vibrations from boilers, engines, etc.
 

The absorption of vibrations occurs both axially and laterally, depending on the installation situation or the routing of the pipe. The exact absorption is determined during the piping design process and is defined by various fixing points and deflections.
 

The design is mainly adjusted based on the following criteria:
 

• Installation ratio
• Medium
• Temperature
• Pressure conditions
• Movement stress
• Moisture accumulation

Compensators are designed in different ways:

• In fabric for flanging / tensioning
• In stainless steel for welding / flanging

Brackets are used to secure flue gas ducts as both expansion and fixed points.
 

Brackets are designed based on measurements or according to a drawing of the flue gas duct and the respective construction site situation.

It is important to consider the site-specific conditions, as welded pipes can generate high forces due to thermal expansion.

Fixed points are used to secure the pipe at deflections or along long sections. A compensator is typically placed here to absorb the expansion. The forces generated by the expansions at the fixed points are transferred from the bracket to the building or the steel structure.

Expansion points are used to guide or stabilize the pipe in the direction of expansion and can be designed as half-shells or pendulums.

For both types of fastening, it is essential to ensure that neither structure-borne noise nor temperature can be transferred. To achieve this, temperature-resistant insert bands in the fastening shells are necessary, as well as decouplings at the connection points to the steel structure or building.

A steel structure is typically required when the building conditions cannot accommodate force or weight loads.
 

Often, high installation heights for the connecting pipes are necessary to make pathways in energy centers usable. In this case, expansion, weight, and pipe routing are considered in the design and static calculations to create a custom steel structure.

Flue gas dampers are typically used in connection with combined heat and power (CHP) units, overpressure-operated engines / backup power systems, or in exhaust technology.
 

They either completely seal the flue gas duct to slow down cooling when the boiler is turned off (energy-saving dampers) or are used to regulate the free cross-section in the exhaust path and to close entire pipe sections, e.g., in bypass solutions (throttle dampers).

Further information on Jeremias flue gas dampers can be found here.