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ASME B5.61-2003 pdf download

ASME B5.61-2003 pdf download.Power Presses: General Purpose, ? Single Action, Straight Side Type.
4.3 Energy Capacity (Mechanical Power Press) 4.3.1 Function of the Flywheel. The energy required forperformingpress operations is stored inthe flywheel. During the working portion of the press cycle, the fly- wheel slows down as it supplies the required energy to the drive train. 4.3.2 Function of the Drive Motor. The drive motor restores flywheel energy during the nonworking portion of the press cycle, which may include the interval between press cycles for presses operating in single stroke modes. 4.3.3 Drive MotorSelection. The selection ofthe drive motor is dependent upon the energy requirements. Fac- tors determining the energy requirements are: (a) rated capacity (b) press speed (strokes per minute) (c) press stroke Based on the optimum slide velocity for the material being worked, a longer stroke press will be required to operate at a slower speed than a shorter stroke press. The longer the stroke, the deeper the draw that can be made, and the greater the energy required to sustain the press through the depth ofthe draw. Table 3 specifies typical press speed/drive motor relationships. 4.3.4 Drive Motor/Flywheel Relationship. The usable energy that a flywheel can supply is a function of the ability of the drive motor to tolerate slowdown without overheating. The usable flywheel energy, expressed as a percentage of total flywheel energy, is a function of the motor slowdown. Table 4 specifies the properties of the three types of single speed drive motors that are most commonly used on mechanical power presses. Mandatory Appendix IV provides a method for calculat- ing the usable flywheel energy. 4.3.5 Variable Speed Presses. Unless otherwise spec- ified by the purchaser, usable flywheel energy for vari- able speed presses shall be rated at one-half the maximum speed.
4.4 Structural Capacity (a) Bed and slide design shall be based on symmetri- cally distributed loading of the bed and slide over two- thirds of the left-to-right and front-to-back area dimen- sions of the bed and the slide, respectively. The bed size is normally the bolster area. NOTE: Tool design should be based on distributing full capacity loading of the press over at least two-thirds of the die space. Dies that do not span the slide connections will result in overload of the bed and slide members at full press capacity. (b) Bed and slide design shall be based on the follow- ing allowable deflection criteria: (1) forotherthanprogressive die presses,deflection of the bed and slide to be within 0.17 mm/m (0.002 in./ft) of the left-to-right dimension (2) for progressive die presses
(a) deflection of the bed and slide to be within 0.08 mm/m (0.001 in./ft) of the left-to-right dimension, for dimensions up to 3 000 mm (118 in.) (b) deflection of the bed and slide to be within 0.12 mm/m (0.0015 in./ft) of the left-to-right dimension, for dimensions greater than 3 000 mm (118 in.) (3) measurement of deflection with a distributed load cannotbeduplicatedbytesting. MandatoryAppen- dix V suggests an empirical method of simulating bed and slide loading for testing purposes. This measure- ment is only done upon the request and agreement of the purchaser. 4.5 Loading of a Press Slide 4.5.1 Mechanical Press. For multiple-point presses, the press slide and its connections shall be designed to withstand offset loading as follows (see Mandatory Appendix VI): 3 (a) for a two-point mechanical press, 60% of the rated capacity under each connection (b) for a four-point mechanical press, 35% of the rated capacity under each connection (c) the total load on the slide shall not exceed the total rated press capacity EXAMPLE: For a 4 000 kN press two-point press: (1) 4 000 kN ? 0.6 p 2 400 kN maximum force can be applied by one connection (2) 4 000 kN − 2 400 kN p 1 600 kN maximum force can be applied by the other connection Mechanical presses shall be provided with hydraulic overloads rated at 110% of press capacity. 4.5.2 Hydraulic Press. Nominal press force (kN) multiplied by 0.075 m equals maximum off-center load (kN·m). Nominal press force (tons) multiplied by 3 in. equals maximum off-center load (in.-tons). Calculation of an off-center force requires consideration. EXAMPLE: To determine the load that can be applied at 0.5 m off-center for a 4 000 kN press: (1) 4 000 kN ? 0.075 m p 300 kN·m (2) 300 kN·m/0.5 m p 600 kN 5 TOOLING RELATED CHARACTERISTICS See Figs. 3 and 4.

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