I have in many years wonderd why the boomlength (probably in the whole world) is measured in meter and the pipehole is measured in inch? It would be more correct if the boompipehole/concretehoses in Europe was measured in milimeters, and in USA - as everything else there, also mesaure the boom in feet or yard. They mesaure the concrete in cubicyard so why not mesaure the boomlength in yard?

I think it is because the common unit in contruction in the US (and maybe the UK) is still inches, feet and yards. Everywhere else the metric system is used. Drawings in the Standard system are just made to accomodate. If you look at your pipe, it should say DN 125 or DN112, as those are just reffered to as 5" or 4.5" (the later is really 4.4")

Why do we call a 2"x4" a 2"x4" it's not.

Cause it was before it was.

Sorry, gboom. Even in Sweden we mesauring the boompipe/concretehose in inch, and i don´t know why. Everything in Sweden is measuring in metersystem, but not when it comes to concretestuff - ok, an cubicmeter of concrete is still measuringed in the metersysteme. Even the bolts on my German pumps (Putzmeister) have a inchthread - why not a milimeterthread, the pump is manufactoried in Europe (German)!? German cars have only bolts whith milimeterthreads. I realy know that because i own this year of Audi S3 (but my wife use it 99% - i pump concrete). I know it because when i change to the summerwheels on our maniac-Audi the weelbolts are milimeterthread, but all my Putzpumps wheelbolts is inchthread. Why???  

now I am a little surpised (shocked?)! learn somehting new everyday...what about Volvo and Saab? do you have standard bolts on these trucks? I am surprised that Putz is using standard bolts, since they are built in Germany and sold worldwide

I´m not sure but there is no reason for Volvo and Saab to use anything but milimeterthread in their bolts - they are Swedish cars - and in Sweden is everything very extremly corect and precisly on the Swedish "perfect"way. So i suppose they use milimeterthread-bolts in their cars. But what i realy know for sure is that every Japanese motocross allways use milimeterthreads in their bolts - at least the motocrossbikes which are delivered in Sweden.

rysty 22, it was not so many years ago Sweden leave the inchsystem when measuring woodplank. 2 inch 4 is nowdays called 45 X 95 millimeter on the timberyard. But we still measure the wheght in our Swedish "Hultafors" hammer in oz, you know: 16 oz hammer or 20 oz hammer. I suppose that noone in Sweden knows how much 1 oz is in gram - not even me knows. Why not measure it in gram, so everyone (at least in Sweden) realy know and understand the wheight. But "Hultafors" sledgehammer-wheight is measured in gram. Strange, but thats how it is. Noone in Sweden understand how much a pound, oz, yard and so on, is - before we read a measure-translater. I´m a pumper, thats why i know that 2 inch (hose) is 51 mm. 

Hell then I might start useing mm to measure my dick! 51mm does sound better then 2 inches! HAHA!

haha. Someone once asked me.. Do you know how I get my dick 1 feet long.. I just fold it 2 times.

That was lame, Dipstick....oh by the way did you know that condoms have serial #s on them???? Well they do, you just never have to unroll them that far.

Way back when,there were american manufacturers,our rule of measure was inches/feet.The 1st Schwing came over (28m) metric,Putz entry was buying Thompson Royal.Since the USA resisted the metric conversion it has always been a mixed bag of nuts.Perhaps just where parts/equipment is manufactured or it's destination could factor in.

Just a thought

lets hope they keep the standard in clock time and not go metric.

rusty 22, I agree with you if the pump is manufactoried in America, but if the pump is manufactoried in Europe - where the whole society is built up to the metric-system, then i think it´s more comon sense to use the metricsystem to all bolts and all other diameters and lengths. As it is now, i need to have two whole sets of tools - metric and inch - even if it often works to use a metrictool to an inchbolt. But it is alot of tools to keep in sight.

But i think, because of the American pumpmarket is the biggest, then it will be the inch-system in every pump.