SkyTrak 6042 Operation Manual - Manual (Page 164)

162 Model 6042 Origin 2/04
General Maintenance
C. Boom Chain Inspection
(250 Hour Intervals)
Under normal operating conditions the boom chains will need to be
inspected every 250 hours of operation. The retract chains need to be
exposed and inspected every 1000 hours of operation. Refer to the Service
Manual for the proper procedure. Environmental conditions and dynamic
impulse/shock loads can drastically affect normal operating conditions and
require more frequent inspection intervals.
Environments in which material handling vehicles operate can vary widely
from outdoor moisture to temperature to mildly corrosive or highly corrosive
industrial atmospheres, in addition to abrasive exposures such as sand and
grit. Some effects can be as follows:
• Moisture - Corrosive rusting reduces chain strength by pitting and
cracking.
• Temperature - Low temperature reduces chain strength by
embrittlement. Going in and out of cold storage results in moisture
from condensation.
• Chemical Solutions or Vapors - Corrosive attack on the chain
components and/or the mechanical connections between the chain
components. Cracking can be (and often is) microscopic. Going
from microscopic cracking to complete failure can be either abrupt
or may require an extended period of time.
• Abrasives - Accelerated wearing and scoring of the articulating
members of the chain (pins and plates), with a corresponding
reduction in chain strength. Due to the inaccessibility of the bearing
surfaces (pin surfaces and plate apertures), wear and scoring are
not readily noticeable to the naked eye.
WARNING:
Worn pins, stretched or cracked links or corro-
sive environments can cause chain failure. A chain failure could
result in uncontrolled boom movement, loss of load or vehicle
instability and could cause death or serious injury and/or property
damage.
250
OH2710
OA1490