mth

I'm clueless.

MTH Pumps - Find your Application

Can't you just ask one of the older guys?

I'm not sure, but I think "mth" = metric tons per hour. A metric ton of water is 265 gallons, so you can convert to gpm if you want.

I found the following in a link to ballast pumps:

"The bilge and ballast pump is a vertical, single stage, centrifugal, double suction, direct motor driven unit with a capacity of 600 gpm at 60 feet total head. The bilge pump is primed by an integral centrifugal displacement type priming pump. The air handling capacity of the primer is 34.5 cfm."

In the above, 600 gpm is a capacity in gallons per minute, but it applies at a particular total head, in this case 60 feet. In your case, ton/hr is a capacity too, but it will vary with the total head. Perhaps the 'th' in 'mth' stands for total head. Maybe the 'm' stands for mean or median. I don't know, but maybe some naval person will come to our aid.

As a Cadet Engineer you should at least be able to spell the name of your company correctly. "shel" would be "Shell" I assume.

My guess is that it stands for Maximum Total Head and that the x sign should read "at".

If you would use some punctuation and capitalization your request might be clearer.

GA; that's better than my guess. MTH would thus be like TDH (total dynamic head), which includes elevation differences, piping pressure drop, and velocity head. As the OP surmised, it is a pressure unit, usually expressed as an equivalent height in meters or feet.

The unit "mth" is a common unit in maritime engineering handbooks. It is a unit of pressure and is definitely a unit that is related to head pressure. This is how I understand the unit:

A pump that has 125 mth of working pressure will have approximately 12.5 bar of pressure. This same pump that has 125 mth will have 125 "meters" of pressure which relates it directly to head. It should be noted that this number can be working pressure or maximum pressure and that should be taken into consideration when looking at a pump. Through looking at various ships manuals, it seems that the "mth" unit refers to only water pumps ( from firefighting pumps to MSD discharge pumps). Also, in my experience this unit seems as if it is only used by the shipbuilders and not the company that makes the pumps.

As a disclaimer - This is how I understand this unit, a unit of pressure related to head in meters. My view may be wrong or flawed and a company who produced these products may have a different, more precise answer.

"Meters total head", perhaps? If so, then please update www.acronymfinder.com accordingly.