by Anil Gajjar

GENERAL PROBLEMS

IN HYDRAULIC

PRESS

by Anil Gajjar

INDEX

1. WORKING OF HYDRAULIC PRESS

2. PARTS OF HYDRAULIC PRESS

3. ADVANTAGES OF HYDRAULIC PRESS

4. LIMITATIONS OF HYDRAULIC PRESS

5. PROBLEMS IN HYDRAULIC PRESS

by Anil Gajjar

WHAT IS HYDRAULIC PRESS ?

A hydraulic press is a machine for applying a large lifting or compressive force. Joseph Bramah, of England invented and was issued a patent for his press in 1795. Hydraulic equipments are work on the Pascal law of pressure.

by Anil Gajjar

PASCAL LAW

The pressure throughout a closed system is constant.

by Anil Gajjar

WORKING OF HYDRAULIC PRESS

Since the hydraulic press works on the basis of Pascal's Law, its working is similar to the one of the hydraulic system. A hydraulic press consists of basic components used in a hydraulic system that includes the cylinder, pistons, the hydraulic pipes, etc.The working of this press is very simple. The system comprises of two cylinders, the fluid (usually oil) is poured in the cylinder having a small diameter. This cylinder is known as the slave cylinder.

by Anil Gajjar

The piston in this cylinder is pushed so that it compresses the fluid in it that flows through a pipe into the larger cylinder. The larger cylinder is known as the master cylinder. The pressure is exerted on the larger cylinder and the piston in the master cylinder pushes the fluid back to the original cylinder.

by Anil Gajjar

The force applied on the fluids by the smaller cylinder results in a larger force when pushed in the master cylinder. The hydraulic press is mostly used for industrial purposes where a large pressure is required for compressing metals into thin sheets. An industrial hydraulic press uses the material to be worked upon along with the help of the press plates to crush or punch the material into a thin sheet.

by Anil Gajjar

by Anil Gajjar

PARTS OF HYDRAULIC PRESS

by Anil Gajjar

1. Cylinder - Cylinder assembly consists of a cylinder, piston, ram, packing, and seals. Piston diameter and oil pressure determine the force (tonnage) that a given press can deliver.2. Frame - The main structure of the press containing the cylinder(s) and the working surfaces.3. Stroke Control - Stroke length can be set for any distance within the stroke limits of the cylinder. Adjustments include: top of stroke, pre-slowdown point, and bottom of stroke.

by Anil Gajjar

4. Throat Clearance - The distance from the vertical centerline of the ram to the frame member behind the bed. This distance determines the largest diameter piece that can be positioned with the part centerline under the center of the ram.5. Daylight - The vertical clearance from the top of the bolster to the underside of the ram in its maximum up position. This term sometimes is confused with the mechanical press term "shut height". Shut height is the clearance over the bed with the ram full down. "Daylight" describes the maximum vertical capacity of the press.

by Anil Gajjar

6. Bolster - A plate or structure mounted on the bed. Hydraulic press manufacturers provide a removable bolster on most models.7. Bed - Flat, stationary machined surface that supports the bolster or dies.8. Dual Palm Button Controls - A common method of actuating hydraulic presses. Both buttons must be depressed at the same time to bring the ram down requiring the operator to use both hands. Control circuits include non-repeat and anti-tie down features.9. Work Height - The distance from the floor to the top of the bolster.

by Anil Gajjar

ADVANTAGES OF HYDRAULIC PRESS

1. Full power stroke.2. Built-in overload protection.3. Much lower original cost and operating costs. 4. Larger capacities at lower cost.5. More control flexibility.6. Greater versatility. 7. More compact. 8. Lower tool costs. 9. Safety.

by Anil Gajjar

LIMITATIONS OF HYDRAULIC PRESS

1. Speed. 2. Stroke depth. 3. Automatic feeding equipment. 4. Shock after breakthrough in blanking.

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PROBLEMS IN HYDRAULIC PRESS

1. Oil leakage.2. Abnormal noise produced.3. High fluid temperature.4. Slow operation.5. Cavitational wear generate.6. At high speed tiles is not produced properly.

by Anil Gajjar

1. OIL LEAKAGE

•Low fluid viscosity.•Unclean oil•When filter can’t work properly.•Faults in equipments.•Poor system design.•Incorrect component selection.•Poor quality control tolerances during the manufacturing of a component.•Incorrect overhaul of rebuilt components.

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ABNORMAL NOISE PRODUCED.

•Make a noise pollution.•Decreased efficiency of machine and worker. •Produced faults in machine.

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HIGH FLUID TEMPERATURE.

•Press does not work properly.•Viscosity of fluid is decrease.•Oil leakage.•Reduced equipment performance.•Reduced efficiency of press.

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SLOW OPERATION.

•Production is decreased.•Oil heated speedily.•More time required.

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AT HIGH SPEED TILES IS NOT PRODUCED PROPERLY.

•A faulty tile is produced.•Efficiency of press is reduced.•Die is bracked.•Oil is heated.