Borescope Use
manual, fiber optics are used to transmit light
from a remote source to an opening at the end
The borescope is a precision periscope
of the borescope probe. The use of fiber optics
instrument. It is designed for you to inspect
removes the heat of the bulb from the probe and
the gas path components of GTEs without
eliminates the electrical parts from inside it.
having to disassemble the engine. The bore-
The Wolf and Eder borescopes now in use in
scope probes (periscopes) contain precision
the fleet are the rigid, probe fiber optic illuminated
optics that are easily damaged by rough handling.
type. Both borescopes have been manufactured
Foam-padded carrying cases are provided to
to the same specifications; although some minor
insulate these instruments from shock. The light
design differences exist, their operating principles
projector is in one case, and all the remaining
remain unchanged.
equipment is in the other case. Many different
The three basic items that are required for a
kinds of probes and adapters are available
standard rigid, fiber illuminated borescope setup
from borescope manufacturers. The equipment
(fig. 3-26) are as follows:
described in this manual has been selected
to meet the inspection requirements of the
1. Fiber light projector-A remote unit that
LM2500 GTE. The need to inspect other
supplies the light needed to see the object.
machinery, in most instances, requires additional
2. Fiber light guide-A flexible cable com-
borescoping components of a configuration
posed of fiber strands that transmits the light from
to be compatible with the geometry of that
the light source to the borescope.
equipment. Additional borescope accessories
3. Probes and adapters-A system of prisms
needed to inspect any machine other than the
and lenses surrounded by light carrier bundles that
LM2500 GTE will be described when we discuss
transmit light to illuminate the object. The prism
the inspection of that particular piece of
and lens system returns the illuminated image
equipment.
from the distal tip to the eye.
Figure 3-26.--Wolf borescope equipment.
3-18
