Pump Ops Chap 18 Flashcards
(25 cards)
What angle is considered the maximum for tractor-trailer stability during jackknifing?
60 degrees from the centerline of the trailer
What is the minimum lateral grade correction most apparatus can manage?
Up to 5 percent (≈ 3 degrees)
What size are standard stabilizer pads used under aerial apparatus?
24 x 24 inches (600 mm x 600 mm)
What is the recommended method to measure the travel path of stabilizers before deployment?
Use a short pike pole, arm span, or closet hook
Why should only multi-step deployment be used for stabilizers?
Single full deployment on one side can damage the chassis, torque box, or axles
What grade type is harder to correct: lateral or longitudinal?
Longitudinal grade
What slope corresponds to a 5% lateral grade?
Rise of 5 feet per 100 feet (1.5 m per 30 m)
Why is operating the aerial over the uphill side preferred on grades?
It offers more stability and minimizes lateral and torsional stress
What distance of incline should be avoided when deploying stabilizers on curbs or sidewalks?
Any non-level surface or load-bearing uncertainty should be avoided
What PSI range is needed for pneumatic PTO systems?
50–140 psi (350–980 kPa)
What is the danger of stabilizer slippage on icy or snowy surfaces?
Compromised aerial stability and risk of apparatus movement
What safety device prevents inadvertent dropping of hydraulic jacks?
Steel retaining pins placed below the jack housing
When is it unsafe to engage a hot-shift PTO system?
If the apparatus is not specifically designed for hot-shift engagement
How should stabilizers be deployed when using a four-jack system on level ground?
Lower both stabilizers on one side first, then alternate to level
What is the purpose of cribbing in stabilizer deployment?
To supplement stabilizer support when ground conditions are poor
What is short-jacking?
Setting stabilizers on one side shorter than the opposite side
What precaution must be taken during short-jacking with waterway operations?
Beware of nozzle reaction transferring load to the opposite side
Why should exhaust or water runoff be monitored during cold weather stabilization?
It may melt frozen ground, creating air gaps under stabilizers
How do interlocks and holding valves improve stabilizer safety?
They prevent hydraulic fluid movement, securing the apparatus
What is the final step after raising the stabilizers before driving off?
Return selector valve to neutral and disengage PTO
Why must the stabilizer pads be centered before lowering jacks?
To ensure even weight distribution and prevent slippage
What is the critical positioning factor to avoid on a grade?
Do not park crosswise to the grade
What does IFSTA recommend every time an aerial is raised?
Fully deploy stabilizers and pads
What causes torsional stress in aerial structures?
Unleveled turntable or side-grade deployment
