Back to Information Document HSE 690/13
|1||1967||Failure to non drive side shaft on recently refurbished mill.|
|2||1971||Ejection of contents due to hydrogen ignition as operator unloaded mill wet grinding manages ore. Hydrogen production due to action of steel balls against wet steel lining.|
|3||1973||5' diameter rubber-lined BBM exploded whilst milling manganese dioxide. Over-milling due to operator error.|
|4||1975||Major failure/explosion from over pressurisation.
Hydrogen explosion due to aluminium ear tags in bone.
|5||1980||"Explosion" of 3' 6" diameter rubber-walled BBM. Over pressurisation due to failure of timer to turn mill off. Similar incident had occurred several years before.|
|6||1981||Major failure/explosion of 7' diameter mill.
Over pressurisation caused by overheating due to lack of water/inadequate venting.
|7||1981||Failure of stub shaft/support from fatigue due to age, poor maintenance and wear.|
|8||1983||5' diameter BBM exploded whilst milling damp silicon. Temperature up to 100C which caused hydrogen evolvement and ignition.|
|9||1985||Operator's hands trapped by "bung" against loading floor. Mill not vented.|
|10||1985||Operator's ankles scalded when hot glaze ejected as 'bung' removed.|
|11||1986||Milling molysdendium disulphate with ammonium bicarbonate. Failure of cooling water supply to casing caused overheating and explosion due to over pressurisation.|
|12||1986||As 10 below, but drive end of 6' diameter mill.|
|13||1986||Failure of stub shaft at non-drive end of 7' diameter mill. General fatigue due to age. (Machine 26 years old).|
|14||1987||Explosion whilst in 6' diameter mill milling barium titanate. Over pressurisation (40 psi) due to addition of "dry ice" which caused carbon dioxide formation.|
|15||1988||Major failure/explosion from over pressurisation at bone grinding. Believed to be due to lack of adequate water. Bursting pressure estimated 60 psi+.|
|16||1989||Traumatic failure of concrete support plinth as mill stationary during discharge.|
|17||1991||Major failure/explosion. Over pressurisation due to heating effect caused by lack of adequate water.|
|18||1991||Operator splashed with mill contents as removing "bung" 20 hours after short run. Pressurisation with carbon dioxide due microbe action on sawdust contamination.|
|19||1994||Operator hit in face and eyes with glaze when removing "bung" from 5' diameter mill. Mill running 25 rather than 1 hours.|
|20||2000||Cast iron end plate blew off 7ft diameter mill after 23 hours milling (near to end of cycle). Resulted in significant damage to the end wall of the building in which the mill was housed.|
|21||2000||Large part of cast iron end plate blew off 7ft diameter mill, near to end of cycle (~12 hours). From the texture of the product in the mill, the company deduced that virtually no water had been added to the mill.|