I work with a hydraulic press to press flat objects that have a different area. How can something , for example, that is 10 by 10 be pressed at 150 psi and equal 30 tons but the same exact thing only smaller pressed at 150 psi only have 15 tons acting on it? I know we get what Tons it should be by (Area * PSI)/ 2000 What I do not understand is how equal PSI can result in different pounds of weight being applied to an object? Is the PSI whats moving the hydraulic press up to close and the pounds of weight how tight its pressing whats in the middle?
A 30 ton press operating at 150 psi must have a hydraulic cylinder with a diameter of approx. 22 1/2 inches. Most presses are rated at their maximum force output. The only way that you can change the load applied by the press is to change the pressure applied to the hydraulic cylinder. With 150 psi hydraulic fluid furnished to the ram or cylinder your press will always have an output of 30 tons, If the press die is 100 inches square, the pressure that will be applied by the die will be 30 tons = 60,000 pounds/100 sq. inches = 600 psi.
It is a pressure in POUNDS PER SQUARE INCH. If you relate this to the area of a hydraulic piston, you will get the total down force on that piston. Force x area is what pressure you get, that's correct, so if you applied the total force to this hydraulic piston and fitted a tool of 1 square inch in the press, you would be applying ALL the pressure from the piston to a much smaller area. Say you have a 10 square inch piston area, and 1000 PSI. The total thrust on the piston will be 10, 000 lbs. If you put a tool in this press that has an area of 1 square inch, the thrust applied to it would be 10,000 lbs/ sq in. You are under a misconception so far as the tonnages you are applying in your work. The press will have to deliver greater force on your 10 x 10 inch whatever, you say 30 tons. OK. Now you put a whatever of much smaller area in it, and the press only needs apply 15 tons to do the job. Naturally, that would have to be correct, if you went on to apply 30 tons to the smaller whatever, it would be very flattened indeed! Try it! So less pressure is needed, to deform a smaller area of a whatever to the desired ? Thichness?. It does not relate to the pressure the press is CAPABLE of delivering.
Northern tool sells them new. Fabrication shops,earthmoving companies, machine shops,and many trucking companies have equipment big enough to need a press that big. Keep an eye out for businesses that are moving or closing down. Hope this helps.
