General Description - Kirby Morgan 77 Operation And Maintenance Manual

Kirby Morgan 77
®
1) The face port (or view port) area remains un-
changed from the SuperLite
2) The helmet is cast as a single piece and finished
using computer controlled machinery. The bottom
helmet ring receives the neck dam ring which seals
to the helmet with an O-ring. The seal is very air/
water tight. The metal bottom of the KM 77 is quite
durable in normal use, but care should be taken not
to drag the helmet bottom on the deck.
3) The neck dam on the KM 77 is sandwiched be-
tween the neck dam rings, securely holding it in place.
Replacement neck dams install easily. Latex or foam
neoprene neck dams are available.
4) When the neck dam/neck ring is locked into place
on the helmet, it is located up inside the protective
helmet ring (that the neck ring O-ring seals to) which
protects the neck ring and neck dam from side impact
damage during the dive.
5) The neck dam design (latex or neoprene foam)
helps position the helmet correctly. Replacement
neck dams should only be genuine KMDSI/Kirby
Morgan neck dams to assure proper operation and
comfort. An internal adjustable chin strap helps to
secure the diver's head in the helmet.
6) The locking collar design holds the neck ring in
the sealed position. The O-ring seal is continuous
once the neck ring enters the helmet ring.
7) Attached to the locking collar is an adjustable
neck pad that should be adjusted to the diver prior
to diving. This will improve the fit and performance
of the KM 77.
8) A system of two sealed pull pin locks is on the
KM 77. One lock is located on each side of the hel-
met. The spring and sliding shaft of these locks are
inside an O-ring sealed main body. The interior of
the main body is filled with silicone fluid. No fine
sand or other debris can reach the interior of these
locks to interfere with their operation.
9) The head cushion attaches just inside the bottom
of the helmet, keeping it in place when the diver
dons the hat. The standard head cushion consists of
a brushed nylon bag with an open cell polyester foam
inside. The 17B head cushion should not be used in
the KM 77 because the design of the head cushions
is different. Only genuine Kirby Morgan KM 77 head
14
-17B.
®
© ⅯⅯⅩIⅡ Kirby Morgan Dive Systems, Inc. All rights reserved. Document # 130318003
cushions should be used to assure proper operation
and comfort.
10) The handle that is fitted to the top of the helmet
and the port weight are areas that can be used as
mounting brackets for lights, TV cameras, etc. Re-
moval of the handle is quick and easy and does not
require sealing it to the helmet shell.
11) The communications system is a modular, quick
change design.
12) The exhaust system is a three valve design, the
REX , that helps to keep the helmet exceptionally dry.
®

2.9 General Description

2.9.1 Helmet Shell
The helmet shell and neck ring is fabricated of stain-
less steel as a one piece assembly. This shell is the
central structure for mounting all the components
that make up the complete helmet. It is designed to
allow easy replacement of parts when necessary. Any
repair to the helmet shell must be done at an approved
KMDSI repair center.
2.9.2 Gas Flow Systems
The main gas supply flow from the umbilical enters
the system at the adapter and flows through the one
way valve to the interior of the side block. The
one way valve or "non-return" is a very important
component.
The one way valve prevents the flow of gas out of
the helmet to the umbilical in the event of a sudden
lowering of pressure in the umbilical. This can hap-
pen due to an accidental break in the hose or a fitting
near the surface. Not only would the emergency gas
be lost if the one way valve failed (concurrent with
a hose or fitting break on deck), but the diver could
suffer from a serious "squeeze" that could cause
injury or death.
Although we have selected the valve for its reliability
and quality, inspection and maintenance of this valve
must be done regularly. It is very easy to disassemble
and inspect. (A rebuild kit for this valve is available).