Survey Procedure

Almost all problems associated with rotary vessels can be attributed to misalignment.

Although the current trend is towards 'soft' non-contact measurements taken from areas outside the hot air envelope along the vessel, there are inherent problems associated with this technique, such as:

• Temperature front refraction
• Variable light conditions
• Oblique angles
• Unbalanced geometric networks
• Limitations of electronics in harsh environments

Some of these factors are not quantifiable and their impact may vary from one day to the next.  Other factors do not even allow proper closing out of the survey in accordance with good surveying practices.  We believe too much unquestioned acceptance of digital read-outs has lead to many of the problems we have been commissioned to rectify.

These problems led Australian Kiln & Mill Services Pty. Ltd. to revert to the basic, more direct (albeit less comfortable) approach by working entirely within the hot air envelope with 'hard' contact measurements to the various critical components as required for evaluation of alignment status.  ‘DIRECT METHODS ARE BEST METHODS’.

Australian Kiln & Mill Services Pty. Ltd. also believes that identification of alignment at the running centres, which after all are the only points at which adjustments can be made, is more practical and realistic approach to achieving meaningful results.

The Australian Kiln & Mill Services Pty. Ltd. alignment procedure enables determination of ‘X’, ‘Y’ and ‘Z’ co-ordinates of the running centres (tyres and rollers), the only places alignment adjustments can be made.  From this information the alignment status of the vessel can be identified.

The following should be considered:

• Some measurements are more critical than others.  For example, measurements between stations need not be as precise as those taken around each station.
• Correct alignment of running centres and surfaces enhance equipment availability and refractory life.
• There is a tendency to finesse alignments when there are too many uncontrollable and unpredictable influences which affect vessel behaviour on an irregular basis.  For example, water table, weather, refractory condition, vessel live load, flame focus and shell hot spots.
• A regular and practical rotary vessel alignment is the best maintenance tool.

An Australian Kiln & Mill Pty. Ltd. alignment package will result in information relating to:

• Current vessel alignment status
• Condition of the tyres and trunnion rollers including tyre chairs and tyre stops
• Tyre and trunnion roller running face profiles
• Trunnion roller inclinations
• Condition of the girth gear and pinion running faces
• Girth gear run-out and meshing status
• Trunnion roller bedplate inclination, orientation and condition
• Actual vessel inclination

All of the above information is supplied, along with alignment adjustment recommendations, on a series of drawings which can be supplied in either hard copy or electronically. Included in the package is a comprehensive mechanical condition report with recommendations for the repair or improvement of the relevant plant items.