Term
| Types of slings used in Arena Rigging |
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Definition
| Wire Rope, Grade 8 Chain, Nylon Webbing and Round slings (Spansets) |
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Term
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Definition
| Extra Improved Plow Steel |
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Term
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Definition
| Independent Wire Rope Core |
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Term
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Definition
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Term
| Shackle "bow" design includes |
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Definition
| Anchor (standard), Chain, and Web |
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Term
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Definition
| Screw pin, Round pin, Nut and bolt |
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Term
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Definition
| Round, Pear, oblong link (master link) |
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Term
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Definition
| Locking latch, Double locking latch, and latch hook |
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Term
| Most common types of hoist (6) |
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Definition
| Electric chain hoist, Pneumatic Hoist, Crane, Ground supported lifts, Electric wire drum winch, Manually operated chain/cable hoist |
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Term
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Definition
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Term
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Definition
| Chain hoist, cable winch puller (come along), block and fall |
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Term
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Definition
| Wraps the sling around a beam so the cable eyes are brother together and shackles to each other. This is the strongest and most common hitch |
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Term
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Definition
| Connects the load directly to a fitting on the beam (an eye bolt, beam clamp, bracket...) |
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Term
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Definition
| Wraps a sling around a beam and shackles the end eye to the standing part of the sling, tightening or choking the beam as load is applied |
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Term
| Direct hitch load capacity |
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Definition
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Term
| Basket hitch load capacity |
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Definition
0° = 200% 60° = 173% 90° = 141%
120°= 100% 150° = 41% |
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Term
| Chocker hitch capacities (Formula, Factor, Angle) |
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Definition
Formula: Sling load capacity X Choker factor X Choker hitch angle adjustment
Factor: Type of material. Wire rope = 70-75%, Fiber Rope=50%, Fiber Strap 75-80%, Chain=70%
Angle Adjustment: 120-180°=100%, 119-90°=87%, 89-60°=74%, 59-30°=62%, 29-0°=49% |
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Term
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Definition
| Single vertical, two verticals, and two angled |
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Term
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Definition
| Dead hang, breast lines, bridles |
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Term
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Definition
| Sling that pulls an objet a few feet or degrees away from vertical |
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Term
| Types of breast lines and descriptions |
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Definition
On object: lesser force used, any horizontal movement causes vertical moment and visa versa. Cannot move the load freely.
On Cable: Requires more force then on object, but you can raise and lower the load without altering position |
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Term
| Most common forms of breast lines |
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Definition
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Term
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Definition
| Simple bridle, Motor bridle, H bridle, 3 leg bridle, 4 leg or compound bridle, diamond bridle |
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Term
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Definition
| 2 legs. one from each beam to the bridle. Used when the desired point location is not directly under a beam |
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Term
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Definition
| Has chain hoists on each leg. Junction location can be moved when one hoist is run up, the other moves down and the point moves horizontally. Useful for fine adjustment to the angle of speaker clusters. |
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Term
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Definition
| Supports two equal loads positioned symmetrically between two beams. Dangerous when the weight on one side changes radically causing the load on the opposite side suddenly to move horizontally and vertically. Useful to hang loads without touching obstruction in middle (like a score board) |
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Term
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Definition
| Used where rigging can attach to the venue structure at fixed points and anchors only. When two anchors are close on one beam, a 3 point 4 leg bridle is safer. |
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Term
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Definition
| May be needed because of load limits or junction position. Not usually practical. Compound 4 leg bridle has four points with 6 legs loads all four anchors. Even if the leg lengths are different. |
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Term
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Definition
| Rare. Breast lines pull sideways away from the obstruction (like a cat walk) |
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Term
| Complete system of fall pro includes but isn't limited to: |
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Definition
| Designed as a complete system by a qualified person. System requires written plans, training, testing, supervision, record keeping, as well as for the design and equipment. Site specific written hazard assessment, Fall protection plan, injured worker rescue plan, equipment design and specifications all conforming to ANSI standard z359.1. Training of workers with records of topics covered, tests of workers with records, periodic inspections of system and usage with records, safety meetings with records |
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Term
| Grade 8 Chain weight per foot |
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Definition
1 lbs/ft for 1 ton
2 lbs/ft for 2 ton |
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Term
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Definition
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Term
| 3/8" Wire rope weight per foot |
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Definition
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Term
| 1/2" Wire rope weight per foot |
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Definition
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Term
| Knots, Bends, and loop knot efficiency |
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Definition
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Term
| Hitchs cut rope strength by |
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Definition
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Term
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Definition
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Term
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Definition
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Term
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Definition
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Term
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Definition
| The distance along the cable it takes for one strand to spiral completely around the cable |
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Term
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Definition
| Breaking Strength / Allowable Load Limit = Design Factor |
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Term
| Most all rigging equipment has a design factor of this or higher |
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Definition
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Term
| Breaking strength is also known as |
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Definition
| Nominal strength, ultimate strength, or tensile strength |
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Term
| Allowable load limit is also known as |
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Definition
| Working load limit of Safe Working Load |
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Term
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Definition
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Term
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Definition
| Maximum breaking strength |
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Term
| Actual design factor formula |
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Definition
| Actual Strength / Maximum Force = Actual design factor |
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Term
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Definition
| Causes maximum force applied to be more than the load weight when ever load is moved |
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Term
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Definition
Maximum force = (Load Weight) (100% + Dynamic Load %)
EXAMPLE:
2000# load is lifted by a hoist that adds 50% DL
2000(100%*50%) = 2000(1.5) = 3000# Max force |
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Term
| Allowable Load Weight equation |
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Definition
Allowable Load Weight = (Actual Strength) / ((Design factor)(100% + Dynamic Load %))
EXAMPLE:
Cable Strength = 10,000#, DL%=35%, Design factor 5:1
((10,000)/(5)(100%+35%)) = 10,000 / (5(1.35)) = 10,000/6.75=1481# |
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Term
| Design factor for hardware should always be |
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Definition
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Term
| Design factor for rope should always be |
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Definition
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Term
| OSHA requires a design factor of WHAT for rigging that supports people |
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Definition
| 6:1 to 10:1 (or higher...?) |
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Term
| The essence of modern engineering for rigging is not designing components.... its.... |
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Definition
| Designing systems using standard components of known strength |
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Term
| Definition of a competent person |
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Definition
| Someone who is able to recognize existing and predictable hazards and who has authority to take prompt corrective action |
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Term
| Rule of thumb for loading truss |
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Definition
Loading is acceptable if the sum of percentages of allowable loads does not exceed 100%.
EXAMPLE:
A center point load is 40% of the max allowable center point load. The uniformly distributed load is 50% of the max allowable uniformly distributed load. The sum is 90% and is under 100%, therefore, acceptable. |
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Term
| Rigging hardware is designed to be loaded in line. When pulling at an angle, the WLL may drop as low as |
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Definition
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Term
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Definition
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Term
| All types of eyes or terminations derate GAC and fiber core ropes to... |
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Definition
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Term
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Definition
| Galvanized aircraft cable |
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Term
| Types of mechanically spliced eyes |
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Definition
| Flemish eye, Return eye, Hand swaged eye |
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Term
| Flemish eye rating and properties |
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Definition
| 95% - If swage is damaged, this eye will retain more strength than the others and makes it the best choice for overhead lifts. |
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Term
| hand swage rating and properties |
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Definition
| 100% with copper or plated copper sleeves are used. Strength is reduced to 75% when Aluminum sleeves are used. Shock load resistance is much worse than copper counter parts. |
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Term
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Definition
| between 1/3 and 1/2 of wire ropes strength |
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Term
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Definition
| Strength loss depends on the bend in relation to rope diameter. Tighter the bend, greater the loss of strength. This is because the outer wire see the highest applied load while the interior wires see little load, or in some instances, compression. Fire ropes show less loss of strength as outer fibers stretch and transfer some of the load to inner fibers |
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Term
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Definition
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Term
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Definition
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Term
| Applied forces are affected by |
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Definition
| Load weight, Geometry and angles of rigging, rolling loads, rain, wind, dynamic loads, people, rythmic bounce, seismic loads, and shock loads |
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Term
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Definition
| Calculated by adding the weight of everything supported item |
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Term
| Geometry of rigging is used to determine the |
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Definition
| tension seen on the cable |
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Term
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Definition
| Max load on support = 2 (Supports weight + Rolling weight) |
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Term
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Definition
| Roofs should be slopped or have drainage or weep holes to allow rain to vacate. Water weights 62 lbs per cubic foot and weights add up quickly. |
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Term
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Definition
| If wind velocity doubles the force to the structure quadruples. For permeant structures code for design is no less than 70MPH |
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Term
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Definition
| Force = Mass X Acceleration |
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Term
| Why is dynamic force caused |
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Definition
| Acceleration and deceleration to a load or more simply put, moving loads. |
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Term
| Dynamic force will always be more than static load. What % should be added for motorized vs manually moved loads according to some engineering texts. |
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Definition
| 50% for manual vs 10% for manual |
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Term
| Most hoists in the entertainment industry move at 16 feet per minute. What is the expected dynamic load increase |
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Definition
| Normally between 20-25%, but may reach as high as 40%. |
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Term
| Dynamic force formula for acceleration |
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Definition
F=(m) (32ft/sec^2 +((Final velocity - Initial velocity)/Time of travel in seconds)) / 32ft/sec^2
EXAMPLE:
Item that is 1,000# at rest travels 5 seconds to 20ft/sec
F=(1,000) (32ft/sec^2 + (20ft/sec^2 - 0ft/sec^2)/5)) / 32ft/sec^2
F=(1,000) (32ft/sec^2 + (20ft/sec^2/5)) / 32ft/sec^2
F=(1,000) (32ft/sec^2 + 4ft/sec^2) / 32ft/sec^2
F=(1,000) (36ft/sec^2) / 32ft/sec^2
F=(1,000) (1.125)
F=1,125lbs of Dynamic force for the 5 seconds of travel |
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Term
| Dynamic force equation for Deceleration |
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Definition
F=(m) (32ft/sec^2 - ((Final velocity - Initial velocity)/Time of travel in seconds)) / 32ft/sec^2
EXAMPLE:
Item that is 1,000# falls at 20ft/sec for 5 seconds to rest
F=(1,000)(32ft/sec^2 + (0ft/sec^2 - 20ft/sec^2)/5)) / 32ft/sec^2
F=(1,000) (32ft/sec^2 + (-20ft/sec^2/5)) / 32ft/sec^2
F=(1,000) (32ft/sec^2 + -4ft/sec^2) / 32ft/sec^2
F=(1,000) (28ft/sec^2) / 32ft/sec^2
F=(1,000) (0.875)
F=875lbs of Dynamic force for the 5 seconds of travel |
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Term
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Definition
| Force = Load (1+(Free fall distance / Stopping distance)) |
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Term
| Dynamic forces are highest when a descending load stops because |
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Definition
| Brake actuation is more abrupt than motor acceleration |
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Term
| Bumping motors to closely together can cause dynamic forces up to... |
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Definition
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Term
| When a person climbs up or on a loaded truss you can expect to see... |
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Definition
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Term
| When a chain link hits the flat side of its lift wheel it is moving at 16ft/sec When the link hits a corner of the lift wheel in rotation it moves the at 16 ft/sec +8%. This causes motors to |
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Definition
| become out of sync over time/duty cycles |
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Term
| What is a seismic load and why is it important |
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Definition
| Seismic loads, or earth quakes, must be accounted for in areas where earthquakes occur. Horizontal forces on a rigged object and the building structure are much lower when there is no horizontal connection bracing between the hanging object and the building structure. |
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Term
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Definition
| Shock loads are when an object drops onto its supporting rigging which jerks the falling object to a stop |
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Term
| Rule of thumb for shock loads |
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Definition
| The greater the falling distance the higher the shock load, the greater the stretching the lower the shock load. Or, as one might say, its not the fall that will kill you, its the sudden stop. |
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Term
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Definition
| A vector is a drawing of a force - a line with an arrow. Two forces (or a vector) applied at the same point can be added to produce a single combined force called a resultant |
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Term
| How do you find the resultant |
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Definition
| Draw the two vectors, starting at the same spot. Draw a dash line from the arrow of vector A, parallel to vector B. Draw a dash line from the arrow of vector B parallel to vector A. Draw the resultant from the point of origin to the intersection of the two new lines |
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Term
| If a basket hitch as a 0 degree angle, what is the strength? |
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Definition
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Term
| If a basket hitch as a 60 degree angle, what is the strength? |
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Definition
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Term
| If a basket hitch as a 90 degree angle, what is the strength? |
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Definition
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Term
| If a basket hitch as a 120 degree angle, what is the strength? |
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Definition
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Term
| If a basket hitch as a 150 degree angle, what is the strength? |
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Definition
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Term
| What is the choker de-rating of wire rope |
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Definition
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Term
| What is the choker de-rating for Fiber Rope? |
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Definition
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Term
| What is the derating of a 120-180 degree choker hitch? |
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Definition
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Term
| What is the derating of a 90-119 degree choker hitch? |
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Definition
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Term
| What is the derating of a 60-89 degree choker hitch? |
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Definition
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Term
| What is the derating of a 30-59 degree choker hitch? |
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Definition
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Term
| What is the derating of a 0-29 degree choker hitch? |
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Definition
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Term
| Forumla to determine de-rating of Choker hitch using a sling |
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Definition
| (SWL of sling) (Choker Factor) ( Choker Hitch) |
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Term
| What is the choker de-rating of fiber rope |
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Definition
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Term
| What is the choker de-rating of fiber strap |
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Definition
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Term
| What is the choker de-rating of chain |
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Definition
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Term
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Definition
| Bags, Hitch or wrap, Shackles, Bridle legs, junction, drop |
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Term
| Advantages and Disadvantages of an H-Bridle |
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Definition
| Objects may move without any notice if one motor is moved. it will both both vertically and horizontally. An advantage to them is if two points need to be hung under a non-load bearing structure like a score board |
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Term
| Four Leg Bridles vs Compound Bridals |
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Definition
| Four points may be needed because of load limits or junction positions, although not practical. Better solution is a compound bridal, 4 point, 6 legs. Will load all 4 anchors even if leg lengths are different. |
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Term
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Definition
| Rare, only used if the only structural support point is directly above a non-load bering obstruction (catwalk) |
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Term
| Fall protection ANZI Code |
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Definition
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Term
| 10 basic fall protection requirements by the US Federal and state law |
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Definition
| 1) Must be designed as a complete system by a qualified person including written plans, training, testing, supervision and record-keeping. 2) Site Specific written Hazard Assessment 3.)Fall Protection plan. 4) Injured worker rescue plan 5.)Equipment design and specs 6.) Vertical or Horizontal life lines, anchors, beams, straps, and personal protective equipment such as harness, lanyards, shock absorbers, hooks, and grabs should meet ANSI standard Z359.1 7.) Training of workers with records of topics covered, instructor, date, and attendees. 8.) Tests of workers to establish understanding of training 9.) Inspections of system and the proper usage of it with records 10.) Safety meetings with records of topics covered, supervisors, date, and workers attending |
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Term
| What size should the main junction shackle be when making a 3/8 cable basket hitch? |
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Definition
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Term
| What size should the main junction shackle be when making a 1/2 cable basket hitch? |
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Definition
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Term
| Hand line should be tied where and using what knot when down rigging a hitch to a top rigger |
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Definition
| Through the eye of the GAC that is connected to the Junction shackle, Bowline |
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Term
| What size should the free shackle be when making a hitch with 3/8 cable |
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Definition
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Term
| What size should the free shackle be when making a hitch with 1/2 cable |
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Definition
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Term
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Definition
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Term
| Efficiency of a Clove Hitch |
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Definition
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Term
| Alpine Butter fly efficiency when pulled from loop, and when pulled end to end |
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Definition
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Term
| Efficiency of a figure 8 follow through |
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Definition
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Term
| Efficiency of a Water Knot |
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Definition
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Term
| When possible, put a shackle in on a *Blank* |
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Definition
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Term
| What is the maximum amount of fittings you can put on a cables eye |
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Definition
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Term
| How many fittings can be put on a hook |
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Definition
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Term
| How thick should the burlap bag be to pad the corners of ibeams after it has been folded |
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Definition
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Term
| For a vertical dead hang, which corners of the beam need to be padded? |
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Definition
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Term
| For a bridle leg or angled dead hang, which corners of the beam need to be padded? |
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Definition
| Both top corners and bottom corner that is opposite leg length |
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Term
| For a chocker hitch, what angles of the beam need to be padded? |
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Definition
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Term
| What is the maximum allowable angle between two points on the bell of a shackle? |
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Definition
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Term
| If the angle is over 90 degrees at a junction, what must be used? |
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Definition
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Term
| When breasting a line using a shackle, what side of the shackle goes on the line and why |
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Definition
| The bell, because if you use the pin, it may unscrew itself |
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Term
| A shackle can be used as a junction point with 3 points on it if the total load is under what % of the SWL |
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Definition
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Term
| When using a shackle to connect a spanset and a GAC stinger, what should its orientation be and why |
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Definition
| The bell of the shackle should be on the span set so that it cannot rotate. The pin should go through the thimbal. |
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Term
| When possible, where should a spanset be place in a bridal leg |
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Definition
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Term
| When putting a round sling on a truss, what are important things to look for? |
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Definition
| That you are putting the truss into compression, and that you are putting the span set at a panel point |
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Term
| Round slings may not be heated about what temp by law? |
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Definition
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Term
| What are some important considerations to note when rigging with span sets? |
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Definition
| Locations of lighting fixtures near lights, location of emergency lights when truss is at trim, location of flash pots, location of anything that can cause harm to span set |
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Term
| What does STAC Chain stand for? |
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Definition
| Special Theatrical Adjusting Chain |
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Term
| What are the rough specs of STAC Chain? |
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Definition
| 1/2" long-link chain (3.75" long), Grade 8 steel, Safe working load of 12,000# |
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Term
| What is the minimum design factor? |
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Definition
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Term
| What is a maximum applied force |
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Definition
| The initial force, along with the factors of dynamic movement, geometry, wind, rain, people, bounce, and shock loads |
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Term
| Maximum applied force must always be, WHAT |
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Definition
| Less then or equal too the allowable Load Limit of a system |
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Term
| Mathematically, what are two ways to represent Max Applied Force? |
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Definition
| (Break Str. X Eff) / Design Factor AND (Load WT X Force Ratio) |
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Term
| Mathematically, how do you represent load weight? |
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Definition
| Max Applied Force / Force Ratio |
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Term
| Mathematically, how do you represent Breaking Str? |
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Definition
| (Design Factor X Max App Force) / Efficiency |
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Term
| What should the safty factor be of running lines? |
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Definition
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Term
| What should the safty factor be a any and all rope? |
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Definition
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Term
| Rule number one of rigging |
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Definition
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Term
| What is the magic number for converting between feet and meters? |
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Definition
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Term
| When converting from metric to imperial you you should... |
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Definition
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Term
| When converting from imperial to metric you should... |
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Definition
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Term
| What is the magic number for converting between centimeters, millimeters, and inchs? |
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Definition
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Term
| When converting from centimeters to inchs you should |
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Definition
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Term
| When coveting from inchs to centimeters you should... |
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Definition
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|
Term
| When converting from millimeteres to inchs you should... |
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Definition
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|
Term
| When converting from inchs to millimeters you should.... |
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Definition
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Term
|
Definition
|
|
Term
| What is the magic number for converting Kilograms and Lbs |
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Definition
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Term
| When converting from Kilograms to Pounds you should |
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Definition
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|
Term
| When converting from Pounds to Kilograms |
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Definition
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Term
| Resultant force shown mathematically = |
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Definition
| (Load)* Multiplying Factor aka...(Sin of Angle / Sin of (Angle/2) |
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Term
| How do you find the multiplying factor of a resultant force |
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Definition
| (sin of Angle / Sing of (Angle/2) |
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Term
| If your angle is 0 degrees, the multiplying factor for a resultant force is |
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Definition
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Term
| Resultant force multiplying factor for 0, 90, 120, and 180 degrees |
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Definition
| 0 - 2, 90-1.41, 120-1, 180-0 |
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Term
| In regards to resultant forces, if your angle is 0 degrees (like with a block and tackle system), and the line is coming off of a stationary pully then... |
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Definition
| Resultant force=Load+Force needed to support the load |
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Term
| In regards to resultant forces, if your angle is 0 degrees (like with a block and tackle system), and the line is coming off of a moving pully then... |
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Definition
| Resultant force=Load -Force needed to support the load |
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Term
| Rule of thumb for determining mechanical advantage |
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Definition
| Count the number of parts of the lift line that are applying force on the running block |
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Term
| IF two lines are used in a mechanical advantage system, how should you determine the ultimate MA |
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Definition
| Multiply left numbers, then multiply right numbers. a 3:1 attached to a 2:1 creates a 6:1 |
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Term
| The number on the left vs the number on the right when dealing with mechanical advantage |
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Definition
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|
Term
| Maximum allowable offset for fleet angle |
|
Definition
1.5 degrees OR 40:1 OR Maximum allowable offset = Distance X .026
(.026 is the tangent of 1.5 degrees) |
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Term
| How do you find the fleet angle |
|
Definition
| Angle = Arc Tangent of (Offset Distance/Measurement distance) |
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Term
| Common D:d ratio for wire rope |
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Definition
|
|
Term
| Common D:d ratio for fiber rope |
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Definition
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|
Term
| Not using the proper D:d ratio will result in what? |
|
Definition
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|
Term
|
Definition
|
|
Term
| How to calculate the length of a bridle leg when the vertical and horizontal is known |
|
Definition
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|
Term
| How do you calculate the angle of a bridle mathematically |
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Definition
| Angle = (Arc Tangent (H1/V1))+ (Arc Tangent (H2/V2)) |
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Term
| As a general rule, bridles with an angle exceeding 120 degrees will have... |
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Definition
| At least one of the legs will be greater than the load being lifted |
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Term
| Mathematically, how do you calculate tension on a bridle leg |
|
Definition
Tension on L1 = Load X (L1 X H2)/((V1 X H2) + (V2 X H1))
Tension on L2 = Load X (L2 X H1)/((V1 X H2) + (V2 X H1))
SAME DEMONINATOR |
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Term
| Mathematically, how do you calculate the vertical force on a bridle |
|
Definition
VF1 = ((V1)(H2)(LOAD))/((V1 X H2) + (V2 X H1))
VF2 = Load - VF1 |
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Term
| Mathematically, how do you calculate the Horizontal force on a bridle |
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Definition
HF1 = VF1 X (H1 / V1)
HF2 = VF2 X (H2 / V2)
^^^BOTH OF THOSE MUST EQUAL (or nearly the same depending on rounding...)
Could also use...
HF = Tension on L1 X (H1 / L1) |
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Term
| Mathematically, How do you calculate horizontal force on a breast line |
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Definition
| Horizontal force = Load X (H1 / V1) |
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Term
| When setting up a 3 point bridle mathematically, what is the first thing you should do |
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Definition
Create a chart for each point that consists of its X, Y, and Z. so...
Point 1 X1=? Y1=? Z1=?
Point 2 X2=? Y2=? Z2=?
Point 3 X3=? Y3=? Z3=?
Point 4 X4=? Y4=? Z4=?
**Point 4 is the junction of all 3 points |
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Term
| When solving for a 3 point bridle, if the Z height is the same for P1,P2, and P3, what could be done... |
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Definition
Set P1, P2, and P3 Z position to 0. Set P4 Z position the distance below the 3 other points.
Example. If all of your beams are at 50', and your point wants to be at 35', set P1-3 Z to 0, and P4 to -15, because it is 15' below the 50' steel. |
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Term
| Mathematically, how do you solve for the leg lengths of a 3 point bridle |
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Definition
L1=SQRT(X1-X4)^2 + (Y1-Y4)^2 + (Z1-XZ4)^2
L2=SQRT(X2-X4)^2 + (Y2-Y4)^2 + (Z2-XZ4)^2
L3=SQRT(X3-X4)^2 + (Y3-Y4)^2 + (Z3-XZ4)^2 |
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Term
| When calculating the tensions for a three point bridle, what is the first step |
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Definition
Create formula matrix:
N1X=(X1-X4)/L1 N1Y=(Y1-Y4)/L1 N1Z=(Z1-Z4)/L1
N2X=(X2-X4)/L2 N2Y=(Y2-Y4)/L2 N2Z=(Z2-Z4)/L2
Same thing for N3X.... |
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Term
| What is the formula for finding the Divisor for a 3 point bridle tensions? |
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Definition
| D=(N1X N2Y N3Z) + (N2X N3Y N1Z) + (N3X N1Y N2Z) - (N3X N2Y N1Z) - (N2X N1Y N3Z) - (N1X N3Y N2Z) *Remember diagonal top left down to the bottom right followed by the bottom left to the top right. Go through all 3. |
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Term
| When calculating tension on a 3 point bridle, after you have found the leg length, and Divisor, what is the next set of formulas you need? |
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Definition
F1=((N2X N3Y) - (N3X N2Y)) X (F/D)
F2=((N3X N1Y) - (N1X N3Y)) X (F/D)
F3=((N1X N2Y) - (N2X N1Y)) X (F/D) |
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Term
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Definition
| Length X Height OR Horizontal X Vertical |
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Term
| Rectangular Volume Forumula |
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Definition
| Length X Width X Height OR Horizontal X Vertical X Depth |
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Definition
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Term
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Definition
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Term
| Cylindrical Volume formula |
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Definition
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Definition
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Term
| 3 Types of stretching that a fiber rope will undergo along with their properties |
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Definition
Constructional stretch : Initial stretch over the first few times the line is loaded. Will keep this stretch forever.
Elastic Stretch: Happens as line is loaded. Varies depending on the rope material. Will disappear when the load is removed.
Creep: A slow elastic stretch under load that is recovered as the load is removed. |
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Term
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Definition
| Horizontal Force = (Height/Vertical)(Width) |
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Term
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Definition
| Slope is the horizontal distance divided by the verical distance, or Slope = Horizontal/Vertical |
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Term
| Horizontal force of a angled dead hang |
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Definition
Slope X Weight
Slope X Weight on the Left = Slope X Weight on the Right |
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Term
| Center of Gravity formula |
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Definition
The weight of the center of gravity is the sum of all the individual weights. CG=W1+W2
To find the location of the center of gravity on an object is( (W1 X Distance)+(W2 X Distance)) / Toal Weights
For X, Y, use separate formulas CGX, CGY, CGZ = (same formula) |
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Definition
| A force applied at a right angle to a line from a the center of rotation X the distance from the force to the center of rotation |
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Term
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Definition
| F1 = (D2/Span)W and F2=(D1/Span)W |
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Term
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Definition
Cantilevers create a load on the closest support that is greater than the point load weight itself. This weight is an upwards force and as such decreases the load on the second point.
F1 = (D2/Span)W and F2=(-D1/Span)W
D1 becomes negative to show the upward force is subtracted from the downward force |
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Term
| Whats forces need to equal each other on a cantilever |
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Definition
The load on each of the load bering points (F1 and F2) must equal the truss weight plus the point load weight.
F1 + F2 = Truss Weight + Point Load |
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Term
| How do you calculate the load percentage of each point on a truss. Assume it is a UDL (Uniformly Distributed Load) - 2-7 points. |
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Definition
Points-Exterior, interior
2-50
3-25,50
4-16.6,30.3
5-12.5, 25
6-10, 20
7-8.3, 16.6
100% divide by the open SECTIONS not points. Divide by 2 for both exterior points. |
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Term
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Definition
A Resultant is the vector sum of the forces
Resultant = (tension)(Angle factors) |
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Term
| Common Angle factors for resultant forces |
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Definition
20°-1.97 30°-1.93 45°-1.85 65°-1.69 75°-1.59
90°-1.41 120°-1.0 145°-.6 175°-.09 |
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Term
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Definition
| Load Weight / Number of parts of rope on load |
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Term
| Load on support for block and fall systems |
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Definition
| Load on support = (# of parts of rope on stationary block/# of parts of rope on load)(Load/Weight) |
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Term
Dead hangs 0°-30° are...
Dead hangs 30-45° are...
Dead hangs 45°+ should... |
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Definition
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Term
| Max force a falling person can be subjected to: |
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Definition
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Term
| When must fall protection be used in regards to an open edge |
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Definition
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Term
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Definition
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Term
| Handrail OSHA requirements |
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Definition
| 42" tall with mid rail at 21" and a rating of 200lbs or more |
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Term
| D-ring and Snap hooks minimum tensile strength |
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Definition
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Term
| According to OSHA, what is the maximum free fall distance allowable for a human |
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Definition
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Term
| Lifelines must have a design factor of 5000lbs per.... |
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Definition
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Term
| 1/8" 7x19 minimum breaking strength |
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Definition
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Term
| 3/16" 7x19 minimum breaking strength |
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Definition
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Term
| 1/4" 6x19 IWRC minimum breaking strength |
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Definition
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Term
| 1/4" Gac minimum breaking strength |
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Definition
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Term
| 5/16" 6x19 IWRC minimum breaking strength |
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Definition
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Term
| 5/16" Gac minimum breaking strength |
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Definition
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Term
| 3/8" 6x19 minimum breaking strength |
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Definition
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Term
| 3/8" GAC minimum breaking strength |
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Definition
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Term
| 1/2 6x19 minimum breaking strength |
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Definition
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Term
| 1/2" GAC minimum breaking strength |
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Definition
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Term
| 5/8" 6x19 IWRC minimum breaking strength |
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Definition
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Term
| 5/8" Gac minimum breaking strength |
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Definition
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Term
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Definition
| Uniformly Distributed Load |
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