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DROPSGuidance

Reliable Securing Booklet Rev 04

Publisher
DROPS · DROPS — Dropped Objects Prevention Scheme
Type
Guidance
Date
Unknown
Themes
Crane and RiggingDropped ObjectsWorking at Height

Summary

DROPS handbook on reliable securing of tools, equipment and structures at height to prevent dropped objects, with best-practice recommendations.

Summary written automatically from the title and document text.

Themes: crane and rigging, dropped objects, working at height.

Extract from the document (first pages)

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Preface

Dropped Objects continue to present significant safety and operational challenges in all areas of business, particularly during dynamic activities, lifting and working at height. Industry statistical data continues to show that a significant number of high potential incidents can be attributed to dropped objects. Interrogations of these incidents highlight a wide range of contributing factors including behaviour, design, work processes, environment and the inappropriate securing of equipment, tools and structural components.

This revision of our ‘Best Practice’ DROPS would like to thank all DROPS handbook consolidates Reliable Securing members and industry specialists who as Industry's principle source of dropped have taken time to assist and contribute object prevention recommendations and towards this latest edition. risk management guidance. Reliable Securing reflects a spirit of The content is relevant and adaptable collaboration, sharing knowledge and across all sectors, promoting the experience for the benefit of all in the opportunity to focus on the underlying fight against dropped objects. causes, to identify and assess the hazards and to apply appropriate DROPS Reliable Securing Workgroup preventive and mitigating controls. September 2017

We remind all readers that the content of this handbook expresses the consensus of opinion from a broad cross-section of DROPS global membership, including manufacturers and technical authorities. Where illustrated, 'Best Practice Recommendations' reflect the generic principles for appropriate selection, application and integrity of securing methods and focuses on associated challenges and considerations.

This booklet is not a product catalogue. Example images are shown for guidance purposes only.

To contact the Group responsible for the publication of this document, please email admin@dropsonline.org

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Contents Hoisting, Lifting and Hoisting, Lifting and Suspended Items Correct Use of Shackles 58 60 Suspended Items Sheaves and Snatch Blocks 62 Introduction 4 Banana Block / Roller Sheaves 64 DROPS Reliable What is Reliable Securing? 5 Synthetic Web Slings 66 Securing Lifecycle Opportunities 6 Wire Rope 67 Eye Bolts and Eye Nuts 68 Hooks 69 Galvanic Corrosion 8 Hanging Hoses and Service Loops 70 Securing Methods Bolted Connections 10 Plate Pad Eyes and Lifting Eyes 72 Reliable Securing of Bolted Connections 11 Specialist Lifting Accessories 73 Locking Wire 16 Chain Hoists 74 Split Pins / Cotter Pins 17 Safety Securing Devices (Wires, Connectors) 18 Installation of Wire Clamps 20 Grating, Hatches, Doors, Access Panels 76 Safety Nets and Meshes 21 Securing Structural Piping and Equipment Feedthroughs 78 Items and Sundries Guard Rails 80 Toe Boards 82 Understanding Dropped Objects 23 Swing Gates 84 Understanding DROPS Calculator 24 Ladders 86 Dropped Objects Responsibilities 26 Wind Walls 88 Signage 90 Cladding 91 Risk Management Task Planning and Risk Assessment 28 Preventive and Mitigating Barriers (Controls) 30 Lighting Units 92 Securing Electrical CCTV Cameras 94 General Tips for Dropped Object Free Worksites 36 Equipment and Crane Boom Camera and Pivoting Floodlamps 96 General Tips for Instruments Securing Equipment During Severe Weather 37 PA Loudspeakers 98 Dropped Object Observation Techniques 38 Junction / Control Boxes and Cabinets 100 Free Worksites Unnecessary Equipment at Height 39 Cable Trays and Ladders 102 Post Inspection / Final Check Of The Worksite 40 Antennas, Windsocks and Sensors 104

Workplace Best Practice 41 Valve Wheels and Handles 106 Working at Height Moving Equipment Securing of Personnel 42 Chain Operated Valves 108 Derrick Evacuation Equipment 44 Cargo Inspections 110 Securing Tools <5kg / 11lbs 46 Securing Tools >5kg / 11lbs 48 Tool Cabinets for Work at Height 50 Material Storage Storage of Cylinders 112 Securing Other Portable Equipment 52 Racks and Shelving 114 Securing Equipment and Parts 54 Mobile Elevated Work Platforms 56

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Introduction What is Reliable Securing? This document is intended to help eliminate the risk of dropped objects. It In simple terms, Reliable Securing is the appropriate selection, application and embraces the requirement for worksite hazard management and illustrates best management of all fastenings and fixings. To achieve and assure the required practice recommendations for Reliable Securing. levels of performance, these should be designed accurately, installed properly and maintained consistently. The content applies to all personnel, tools, equipment and structures associated with design, supply, transportation, installation, maintenance, operation and Reliable Securing provides RELIABLE SECURING DEFINITIONS dismantlement activities across industry. a safeguard against potential yielding, displacement or failure Primary Fixing Reliable Securing is an independent Whilst it may be impracticable to adhere of fastenings which can lead to The primary method by which an item is publication developed in close to all the recommendations, the content equipment or structure falling. installed, mounted and secured to prevent the collaboration with equipment suppliers sets a standard we should aspire to. item falling, (eg bolted connections, screws, This revised edition of DROPS and users. It's purpose is to disseminate pins, buckles, clips, welds etc.) Should you choose to adopt Reliable Reliable Securing demonstrates knowledge and best practice. Securing best practice, the onus is on you dependable retention methods Secondary Retention In many cases, the recommendations to effectively manage any subsequent and technologies. The engineered method for securing the presented in this handbook will identify changes to existing equipment, systems primary fixing to prevent loss of clamping force opportunities for improvement. and working practices. Reliable Securing reduces the Probability of dropped objects or displacement of fastening components, (eg through good design, planning, locking washers, locking wire, split pins / cotter inspection and application pins, etc.) The recommendations presented in this document do not affect, of preventive controls and Also referred to as Second Barrier or Fail Safe replace, or supersede any applicable industry Codes, Standards, barriers. feature in some engineering descriptions. Type Approvals or OEM Recommendations.

Please be advised: Reliable Securing reduces Note: Double Lock-nutting or Dual Nutting is the Consequences of dropped NOT recommended as a reliable method for • Any modifications made to equipment, tools, structure or working objects through implementation retaining loads in tensioned bolting. methods - even if they provide a safer solution – will be subject to of appropriate safety securing Management of Change. systems, mitigating practices • Always identify Original Equipment Manufacturer (OEM) and processes. recommendations with regard to securing. (In many cases, appropriate Safety Securing Reliable Securing outlines the retention methods may already be integrated or are available on request.) key factors that contribute to An additional mechanism for securing the • Always identify all associated ownership, maintenance, inspection and dropped objects and identifies item to the main structure, suitably selected to certification of equipment, tools and structures. opportunities to improve restrain the item or its components from falling • Always confirm that you have the authority, knowledge, experience hazard identification and risk should the primary fixing fail, (eg rated steel or and skills to proceed before applying any of the tools or techniques assessment processes. synthetic nets, lanyards, baskets, wires, slings, presented in this document. chains etc.)

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Lifecycle Opportunities We are all exposed to dropped objects at every stage in the lifecycle of structures, equipment and operations. We have the opportunity to introduce improvements at every stage from design and manufacture through to dismantlement. An important goal has been to define barriers that will prevent objects falling. These barriers should be considered in the design, procurement, transportation, application and maintenance of all structures, tools and equipment, particularly where they are used, secured or stored at height.

Design processes should accommodate During transportation, apply cargo key stages where DROPS best practice handling best practice through vigilant recommendations can be incorporated. inspections and adherence to procedures. When procuring, manufacturing and Throughout operational life, always consider fabricating new assets, tools and the potential for dropped objects caused equipment, identify and incorporate by poor behaviours, inadequate securing, integrated barriers and safety systems. corrosion, vibration, environmental factors and much more besides. When modifying equipment and assets or moving to new territories, carefully consider potential dynamic and environmental effects Above all, be aware that dropped on retention techniques and systems. objects happen everywhere. Management of Change is essential in Be sure to identify each dropped maintaining integrity and design intent for object hazard in every task. all tools, equipment and structure. The recommendations set out in When installing new or temporary this handbook should be followed equipment, always evaluate the risks throughout the full value chain; associated with the chosen location in order from engineering design through to minimise the danger of dropped objects operational life and with special caused by snagging, collision or vibration. attention to lifting, work at height and transportation. This is the fundamental basis for Adherence to each of these eliminating dropped objects and, recommendations will help us all as such, all designers, suppliers achieve our goal of zero harm and and buyers should be aware of damage from dropped objects. these recommendations. Typical Lifecycle Opportunities

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Graphite

Galvanic Corrosion Titanium

Silver

Cathode (more noble metal) As a basic rule, only metal of the same or almost the same nobility should be Acid-proof steel A4 – passive combined in a corrosive environment. Stainless steel A2 – passive Galvanic corrosion occurs when two dissimilar metals with different voltage potentials are in contact with each other in the presence of an electrolyte (damp film or seawater / fresh Iconel – passive water). When this happens, the less noble metal becomes the anode and the more noble metal the cathode. Nickel – passive

Silver solder For example, if a steel bolt is fixed into a stainless steel plate, the bolt will become BOLT Environment Monel the anode since stainless steel is the Anode Copper/nickel alloys nobler metal. Bronze The bolt will rust rapidly as the Electrolyte STAINLESS difference in potential is greater. STEEL Copper

Brass

If the same steel bolt is fixed into, or is in Tin BOLT Environment

Anode (less noble metal) contact with a less noble material, eg a Lead zinc plate or washer, the bolt will become Cathode the cathode and will not rust. Tin solder The zinc will corrode, as it is less noble Cast steel than the screw. Electrolyte ZINC PLATE

Steel and iron

Aluminium 2024 – T4 Always consider the potential for galvanic corrosion where new Cadmium materials such as passivated stainless steel are introduced. Certain working environments apply strict controls and guidance with Aluminium 1100 regard to the introduction of alloys. Always check first. Galvanised steel

Zinc

Magnesium alloys

Magnesium

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Reliable Securing of Bolted Bolted Connections Connections At present, bolts are being produced to at least 85 different industrial standards Flexing of bolted structures and vibration or shock loading in machinery can and the requirements for bolted connections vary for the different sectors cause bolted joints to loosen, disengage or shear. Thermal cycling may also cause depending on design, operational and maintenance requirements. nuts and bolts to become loose.

Loose nuts and bolts can lead to joint failure and dropped objects, resulting in Achieving a stable bolted connection will Reasons why bolted connections and avoidable incidents and unscheduled downtime. therefore require a qualified evaluation of the fastenings fail: following factors: To prevent nuts and bolts from • Load design loosening, a reliable, proven To distinguish between bolt Improper use/ secondary retention method types and retention suitability, • Choice of materials with a view to installation (30%) should be used. we have presented best practice mechanical properties and corrosion resistance Vibrations (20%) recommendations in two groups This is particularly important namely; • Pre-loading (pre-tensioning) and use of the Knocks (12%) where maintaining the clamping correct torque equipment force across the bolted Bolted connections where clamping Overloading (11%) connection is critical to its force is critical (eg Tension Joints), • Any effects upon the integrity of the Wear (6%) integrity. fastenings caused by the operational Bolted connections where clamping environment, lubrication etc. force is not critical (eg Shear Joints). Corrosion (5%) Typically these factors will be verified by OEM recommendations, Engineers or Fastener Source: PSA, 2008 Industry Specialists and should be consulted Preload is the tension created in a fastener when it is tightened. prior to any maintenance or modifications. The tensile force creates compression in the bolted joint (clamping force). If the correct preload is not applied, secondary retention devices are less likely to retain the clamping force. DOUBLE NUT/DUAL NUTTING – NOT BEST PRACTICE Torque is the application of Several independent industry tests force that creates tension in show that double nut, jam nut or the bolt. Tension generates a clamping force between dual nutting arrangements are the two parts to achieve the not reliable methods of securing desired 'preload'. screwed / bolted connections When preload is required, and are particularly unsuitable for engineering design and retaining loads in tensioned bolting. manufacturing will determine The practice of dimpling threads is the most appropriate retention also inadvisable. methods.

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Reliable Securing of EXPANDING PIVOT PIN

Tension Joints The system consists of an assembly that includes an axle (tapered at both ends), expansion sleeves, tension washers and fasteners. When the fasteners are torqued, the Here we illustrate secondary retention for tensioned bolted connections, eg nuts tension washers push the expansion sleeves and bolts tightened with a suitable tool to the appropriate design load, typically up the tapered part of the pin, thereby locking used for the securing of mechanical and structural joints. the system into the lug ears and eliminating movement that causes pivot wear. The following methods are recommended for mechanical and structural connections The double-sided locking mechanism provides where maintaining the clamping force is critical. increased stability, security and a backlash-free joint. Installation can be easily done in the field, reducing downtime and cost WEDGE LOCK WASHERS Used on top drives, pipe rack cranes and other Wedge Lock washers safely secure bolted joints pipe-handling equipment. against loosening caused by simple flexing, vibration and shock loading. Wedge locking technology secures bolted joints with tension instead of friction, allowing lubrication MULTI-BOLT TENSIONERS to aid assembly and maintenance. The system Available as nuts or bolts as replacements comprises of a pair of lock washers that have for conventional bolting elements. They cams on the inner face and radial teeth on the only require hand tools for installation and outer face. removal, eliminating requirements for hydraulic Almost unlimited use in bolted joints where reliable tightening equipment. Their design makes securing or secondary retention is required. them resistant to loosening caused by dynamic loading. Particularly useful for larger fasteners and Surface material compositions may influence washer selection. where tightening is difficult at height and in Always refer to OEM data sheets to verify application requirements. restricted spaces.

THREAD PROFILE LOCKING To identify and establish the suitability of each bolting method, The nut has a specially designed threaded profile always consult with the manufacturer, plant owner or operator. that locks when tightened and distributes the For further guidance, consult relevant design and industry codes or tension over the whole length of the thread. standards, or discuss the issue with a Subject Matter Expert. This provides better load distribution, which in turn helps to improve the locking of the screw connection. Also available as a thread insert. Almost unlimited use in bolted joints where reliable securing or secondary retention is required.

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Reliable Securing of CASTLE NUT AND SPLIT PIN

Other Bolted Connections Castellated nuts provide a visual and reliable method for locking bolted connections. The nut has radial slots and is locked by a non-corrosive split pins inserted through a hole in the bolt shank to prevent Here we illustrate secondary retention for bolted connections typically used for movement. securing of equipment components and other ancillary items. Used on connections where clamping force is not required The following methods are recommended for bolted connections where maintaining the (eg the bolt operates as a hinge) and where components are clamping force is incidental and non-critical. disconnected frequently. May also be referred to as Slotted or Crown nuts.

NYLON INSERT NUT These arrangements are only suitable This nut includes a nylon collar insert. The collar deforms for bolted connections exposed to shear elastically as it is applied to the bolt. This increases friction forces. between both sets of threads creating the required purchase for the connection. A versatile fastening for non-critical connections.

SELF LOCKING COUNTER NUT Re-use is not advised. May rotate These nuts cut into the bolt threads when applied and and loosen when exposed to dynamic tightened, and should only be applied over the standard nut loading or excessive UV radiation. once it has been correctly installed and tensioned.

Not suitable for re-use. Low-grade counter nuts may corrode in marine environments. METAL LOCKING NUT Metal locking nuts may be used on all bolt dimensions. This type of nut comes in various forms and may feature a deformed head, split neck or toothed collar ring. WASHERS ADHESIVES Purchase is created by friction, cutting into the thread or contact face. Friction grip relies upon high pre-load and There are various washer types and Thread locking compounds are primarily correct torque. assemblies available, some with used where vibration is moderate and the specific applications and some environment is mild / non-corrosive. A versatile fastening for non-critical connections. that are shown to be ineffective in In selecting this method, be aware that there preventing nut loosening. may be no visible evidence of its application. Lubricating the threads without It is imperative that OEM and Always ensure that any locking compound adjusting torque specifications may lead Subject Matter Expert or Duty is clearly specified on assembly drawings, to over-tensioning of the fastener. Holder guidance is sought on the on Bill of Materials and documented in suitability of washer type / assembly maintenance and operations procedures. for the specific application.

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Locking Wire Split Pins / Cotter Pins Locking wire should only be applied by competent persons specifically trained in its correct

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