Mikevv: Big Blue wasn't to blame for Miller Park collapse.
Bill Lampson, president of the crane company said: I'm satisfied there was nothing wrong with the crane," Lampson said. "There was nothing wrong with the setup of the crane and nothing mechanically wrong."
News accounts from the period...
JohnnieE: You can select a Yaskawa VFD. This kind of inverter will suit to your aplication very good. you can select a decelaration ramp from 1 to 60 sec and up.
Motor must be equiped with a fan (TEFC Motor Type) or if possible attach a separated fan blower.
tmcgett: Yes I repair two overhead cranes.
These new cranes arrive to plant with a very high noise in motor hoists, in first and second step (five step each) but in 3 4 y 5th step operate normal. Silence.
Motor hoists worked like a two phase condition and high amps in wound rotor.
Then I review...
JohnnieE: What kind of motor you will use?
TENV, TEFC etc.?
What are the cycles of work? as an example: 10 min work, 10 min rest or 10 min work 30 min rest? specify
What is the average freq. of work period?
What is the type of work? A pump, a mill, a hoist, a trolley? what type. Indicate
Tobman: recently I needed to do a jib crane then I calculate it as I found in Marks Manual (Mechanical Engineer)Page 5-30 Table 5.2.4. & Table 5.2.5 (Novena Edición en Español)
these are the formulas:
I found a practical method as follows:
You need to calculate beam first like a member...
I need to choose a turn over (upside - down) machine to turn a mould over 90° from upside position to down or down to upside. Muold weight is about 7 ton.
I´m using to do this operation with a 30/5 ton overhead crane but there is a risk in this manner due to 5 ton hook maybe is handling more...
I need to usbstitute and old dc speed controller 5 steps to operate a 15 hp series wound dc motor 550 VDC. 32 amp
This is a hoist motor of an overhead crane.
Can you recommend any brand of electronic dc speed variator cappable to do this?
Any info will be very appreciated.
Thanks
ATVargas