Significance and Use
Materials handling equipment operability and long-term integrity are concerns that originate during the design and fabrication sequences. Such concerns are most efficiently addressed during one or the other of these stages. Equipment operability and integrity can be compromised during handling and installation sequences. For this reason, the subject equipment should be handled and installed under closely controlled and supervised conditions.
This guide is intended as a supplement to other standards (Section 2, Referenced Documents), and to federal and state regulations, codes, and criteria applicable to the design of equipment intended for this use.
This guide is intended to be generic and to apply to a wide range of types and configurations of materials handling equipment.
The term materials handling equipment is used herein in a generic sense. It includes manipulators, cranes, carts or bogies, and special equipment for handling tools and material in hot cells.
This service imposes stringent requirements on the quality and the integrity of the equipment, as follows:
Boots and similar protective covers should not restrict movement of the equipment, should be properly sealed to the equipment and should withstand the radiation, cell atmosphere, dust, cell temperatures, chemical exposures, and cleaning and decontamination reagents, and also resist snags and tearing.
Materials handling equipment should be capable of withstanding rigorous chemical cleaning and decontamination procedures.
Materials handling equipment should be designed and fabricated to remain dimensionally stable throughout its life cycle.
Attention to fabrication tolerances is necessary to allow the proper fit-up between components for the proper installation and mounting of materials handling equipment in hot cells, for example, when parts or components are being replaced. Fabrication tolerances should be controlled to provide sufficiently loose fits where possible to aid in remote maintenance and replacement of equipment and components.
Fabrication materials should be resistant to radiation damage, or materials subject to such damage should be shielded or placed and attached so as to be readily replaceable.
Smooth surface finishes are necessary for decontamination reasons. Irregularities that hide and retain radioactive particulates or other adherent contamination should be eliminated or minimized.
Materials handling equipment that is exposed to high temperatures, pressures, acidic or caustic conditions may require special design considerations to be compatible with the operating environment. Potential rates of change for temperature and pressure as well as absolute temperature and pressure extremes, created by activation of fire suppression systems and other emergency systems, should be considered.
When replacing, modifying or adding additional materials handling equipment to an existing hot cell, maintenance records of materials handling equipment in that hot cell or in a hot cell having a similar processing mission may be available for reference. These records may offer valuable insight with regard to the causes, frequency, and type of failure experienced for the type and class of equipment being designed and engineered, so that improvements can be made in the new equipment.
Preventive maintenance based on previous experience in similar environments and similar duty should be performed to prevent unscheduled repair of failed components.
Scope
1.1 Intent:
1.1.1 This guide covers materials handling equipment used in hot cells (shielded cells) for the processing and handling of nuclear and radioactive materials. The intent of this guide is to aid in the selection and design of materials handling equipment for hot cells in order to minimize equipment failures and maximize the equipment utility.
1.1.2 It is intended that this guide record the principles and caveats that experience has shown to be essential to the design, fabrication, installation, maintenance, repair, replacement, and decontamination and decommissioning of materials handling equipment capable of meeting the stringent demands of operating, dependably and safely, in a hot cell environment where operator visibility is limited due to the radiation exposure hazards.
1.1.3 This guide may apply to materials handling equipment in other radioactive remotely operated facilities such as suited entry repair areas and canyons, but does not apply to materials handling equipment used in commercial power reactors.
1.1.4 This guide covers mechanical master-slave manipulators and electro-mechanical manipulators, but does not cover electro-hydraulic manipulators.
1.2 Applicability:
1.2.1 This guide is intended to be applicable to equipment used under one or more of the following conditions:
1.2.1.1 The materials handled or processed constitute a significant radiation hazard to man or to the environment.
1.2.1.2 The equipment will generally be used over a long-term life cycle (for example, in excess of two years), but equipment intended for use over a shorter life cycle is not excluded.
1.2.1.3 The equipment can neither be accessed directly for purposes of operation or maintenance, nor can the equipment be viewed directly, for example, without shielded viewing windows, periscopes, or a video monitoring system.
1.3 User Caveats:
1.3.1 This standard is not a substitute for applied engineering skills, proven practices and experience. Its purpose is to provide guidance.
1.3.1.1 The guidance set forth in this standard relating to design of equipment is intended only to alert designers and engineers to those features, conditions, and procedures that have been found necessary or highly desirable to the design, selection, operation and maintenance of reliable materials handling equipment for the subject service conditions.
1.3.1.2 The guidance set forth results from discoveries of conditions, practices, features, or lack of features that were found to be sources of operational or maintenance problems, or causes of failure.
1.3.2 This standard does not supersede federal or state regulations, or both, or codes applicable to equipment under any conditions.
1.3.3 This standard does not cover design features of the hot cell, for example, windows, drains, and shield plugs. This standard does not cover pneumatic or hydraulic systems. Refer to Guides C1533, C1217, and ANS Design Guides for Radioactive Material Handling Facilities & Equipment for information and references to design features of the hot cell and other hot cell equipment.
1.3.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices, and determine the applicability of regulatory limitations prior to use.
