ASME B5.60A-2005 pdf download

ASME B5.60A-2005 pdf download.WORKHOLDING CHUCKS: JAW TYPE CHUCKS.
1 INTRODUCTION This American National Standard establishes techni- cal requirements for workholding chucks. There are hazards inherent in the design, use, and operation of jaw type chucks. Ignoring safety considera- tions will result in personal injury, including death. 2 SCOPE This Part of the ASME B5.60 standard covers the safety requirements for jaw type workholding chucks that are primarily used in turning applications. This Part addresses the requirements and/or measures to minimize the hazards and reduce the risks associated with workholding chucks. NOTE: For specific limits and specifications, contact the workholding chuck manufacturer. 3 DESIGN AND CONSTRUCTION OF WORKHOLDING CHUCKS AND TOP JAWS 3.1 Workholding Chucks Original chuck design shall address at a minimum the following: 3.1.1 Chuck and actuating equipment shall be com- patible. 3.1.1.1 The input force of the actuating equip- ment is to meet or exceed the chuck’s requirements. 3.1.1.2 The stroke of the actuating equipment is to meet or exceed the chuck’s requirements (power chuck). 3.1.1.3 The maximum allowable speed of the actuating equipment is to meet or exceed the chuck’s requirements (power chuck). 3.1.2 Chuck components shall be positively pre- vented from being flung out by centrifugal force. 3.1.2.1 The chuck’s internal and external compo- nents are to have design features ensuring integrity at the maximum allowable speed. 12 3.1.2.2 Limits on the mass of top jaws and radial position are to be defined in the chuck’s manual (i.e., the restrictions of speed and input force with regards to top jaws). 3.1.3 Balance of the chuck is to ensure safe opera- tion up to the maximum allowable speed. 3.1.3.1 The chuck and actuator are to be balanced within 3 g at outside diameter as the standard. 3.1.3.2 The chuck’s design is to allow for field balancing (if required). This could be done at the areas of the chuck prescribed for addition or removal of weight as per para. 3.1.3.1. 3.1.4 Chucks shall be equipped with means for the safe handling per ASME B18.15M (e.g., provision for lifting eye bolt). 3.1.5 The chuck’s design is to have a convenient and reasonably accessible method for lubrication of the workholding chuck. 3.1.6 The power chuck and/or actuating equipment shall have stroke detection and/or confirmation provi- sions (e.g., sensing devices). 3.1.7 There shall be provisions to maintain clamping force until the spindle comes to a safe stop in the event of loss of input force. 3.1.8 In the event of power loss, the chuck and/ or actuating equipment shall have provisions to maintain clamping force until the spindle comes to a safe stop. 3.2 Top Jaws Top jaw design shall address, at a minimum, the following: 3.2.1 Top jaws and chucks shall be compatible. 3.2.1.1 Any top jaws used on a specific chuck shall have compatible mating surfaces. 3.2.1.2 Top jaw design must address weight, position, and speed limitations. 3.2.1.3 Top jaw material must be also considered for strength and durability.
3.2.1.4 Replacement top jaws must adhere to original workholding manufacturer’s mounting dimen- sions and tolerances as specified by the chuck manufac- turer. Deviations from these specifications could cause loss of gripping force, damage to the chuck, and possible injury. 3.2.2 Top jaws/components shall be positively pre- vented from being flung out by centrifugal force. 3.2.2.1 The mechanical connection between top jaws and master jaws shall be of an interlocking design that will resist separation, under centrifugal force, when properly connected with the specified fasteners. Other types of stops, blocks, and clamps properly bolted in place may be used. 3.2.2.2 Welded jaws shall not be used. 3.2.3 Jaw nuts and mounting bolts shall be compati- ble with original workholding manufacturer’s specifica- tions. 4 MARKING 4.1 Workholding Chucks Marking shall be durable and last for the life of the product. Minimum requirements for marking shall include the following: (a) manufacturer’s name and model/identification number (b) maximum input force (c) maximum static clamping force. 4.2 Top Jaws Marking shall be durable and last the life of the product. Minimum requirements for marking shall in- clude the manufacturer’s name and/or logo, model and/ or identification number on a visible (when mounted) and not likely to be removed surface. 5 SAFETY INSTRUCTIONS 5.1 Workholding Chucks The original chuck manufacturer shall provide an instruction manual. Items to be addressed in the instruction manual, at a minimum, shall include the following: (a) general specifications (e.g., dimensions, maxi- mum speeds, and forces) 13 (b) instructions for the handling and installation of the workholding chuck (c) instructions for the usage of the workholding chuck (1) jaw forming/boring (2) jaw mounting (3) component clamping (d) methods for determining chuck forces (1) maximum drawbar-pull (Mandatory Appendix I, para. I-1) (2) static gripping force (Mandatory Appendix I, para. I-2) (3) dynamic gripping force and centrifugal force (Mandatory Appendix I, para. I-3) (4) driving torque (Mandatory Appendix I, para. I-4) (5) maximum rotation speed (Mandatory Appendix I, para. I-5) (e) instructions for maintenance (1) assembly and disassembly instructions (2) assembly/component views (3) parts list (4) lubrication instructions (f) periodic performance checks (1) jaw stroke (2) static clamping forces 5.2 Top Jaw Safety Instructions The original top jaw manufacturer shall provide safety instructions. Items to be addressed at a minimum shall include the following: (a) method for calculating the maximum rpm (b) mounting hardware to be specified (e.g., dimen- sions, grade/class) (c) mounting instructions (d) statements to be included: (1) “Follow chuck manufacturer’s mounting and usage specs as outlined in the original workholding manufacturer’s manual.” (2) “Specific limits and specifications: contact the top jaw manufacturer.” (3) “Maintenance recommendations — when ap- plicable.”