Alpha Inspection Services - Single Flue Steel Stacks

rotten steel stackSingle Flue steel chimney stacks are different from most other types of chimney stacks due to the fact that they have no lining and rely upon the structural integrity of the flue for their stability. This allows the structural shell to be in close contact with corrosive gases which, if left unchecked, can often result in extensive defects such as shown in the pictures opposite of a stack that was inspected by Alpha following years of inspections undertaken by other contractors.

Frequent inspections by properly qualified personnel are imperative to identify at an early stage the defects associated with such corrosive conditions. The results of these surveys allow for an early diagnosis of defects, from which a proactive maintenance programme can be established. This enables minimal operational disruption to the clients' production process and allows for repairs to be undertaken during planned shutdown periods without the need for costly imposed outages.

Alpha undertakes two main types of inspection processes on single flue steel chimney stacks dependent upon age and operating conditions. Regular NDT photographic visual examinations using steeplejack ladders and rope access equipment are used on relatively new stacks at periods not exceeding 14 months.

Principal inspections are required on all high risk systems (coal, oil) single flue steel stacks at periods not exceeding 14 months but are only required at periods of 42 months on stacks considered to be low risk such as gas fired systems. These inspections enable defects to be diagnosed at early stages and allow for the correct method of repair to be identified and implemented.

Methods used for undertaking Inspections on Single Flue Steel Chimney Stacks include:

    Steel flue base fault
  • Visual Photographic Surveys.
  • DVD Camera Surveys
  • NDT Ultrasonic Testing
  • Welded Joint Analysis
  • Welded Joint Dye Testing
  • MPI Flange Bolt Testing
  • Emission Flow rate Calculations

Further to the inspection process, Alpha supply detailed structural reports on the condition of the stack along with the necessary repair specifications and costs involved.

All reports are backed up with photographs of defects found during the inspection process, NDT drawings identifying areas of testing and readings obtained.Certificates are supplied in relation to NDT readings obtained and Lightning Conductor Earth Testing.

©2009-2011 Alpha Specialist Contracting Ltd.