Technical Manual

SRT X-BAND RADAR SYSTEMS
ANNEX
304202P003 12 Rev. C
4 Installation Instructions
4.1 Elliptical Waveguide
Elliptical waveguide is supplied pressurised. An air inlet valve is included with
each pressurised length. Gaskets, silicone grease, connecting hardware and
assembly instructions are packed with unattached connectors.
ELLIPTICAL
WAVEGUIDE
TYPE
NUMBER
D
IMENSIONS
OVER JACKET
IN INCHES
(MILLIMETRES
)
V
OLUME
PER 100 FEET
(30 M) IN CUBIC
FEET (LITRES)
R
ADIUS OF
MINIMUM BEND IN
INCHES
(MILLIMETRES)
E-PLANE - H-
PLANE
R
ECOMMENDED
TWIST LIMIT IN
DEGREES PER
FOOT
(METRES)
W
AVEGUIDE
WEIGHT
LB/FT
(KG/M)
EW(85) 1.32 X 0.90
(33.5 X 22.9)
0.42 (11.9) 8 (200) - 19
(480)
1 (3) 0.36 (0.54)
4.1.1 Preparation and Inspection
Inspect waveguide for possible shipping damage and pressure loss. Waveguide
and connector assemblies have been pressure tested at factory before
shipping.
Maximum allowable pressure drop for assembly over 20 Ft. (6.1.m) is 1lb/in
2
(7
kPa) in 24 hours from initial pressure of 10lb/in
2
(70 kPa). Each assembly is
pressurized with dry air to 10 lb/in
2
prior to shipping and result of factory
pressure test is recorded on inspection tag tied to assembly. Tire gauge can be
used to check pressure. If waveguide has pressure loss, check all joints for
possible leaks especially at pipe threads. Refer to paragraph 5.4. for pressure
information.
Factory attached connector is shipped with blank flange attached to maintain
pressure during shipment. Do not remove flange until after waveguide is
installed.
Field attachment of connector at Transceiver end must be completed before
hoisting. Attach connector to end of waveguide in accordance with instructions
in paragraph 5.2.
Pressure test assembly prior to hoisting.
4.1.2 Hoisting
Obtain suitable hoist line to support weight of waveguide. Refer to table above
for weights per foot (metre). Place protective covering over connector to prevent
damage during hoisting. Attach robe sling or cable grip near end of waveguide
allowing sufficient length to reach Antenna Group input from hoisted line to keep
from dangling. Rope sling may be used in lieu of cable grip for every short
lengths. Use cable grips in accordance with instructions received.
Additional tying is done above and below cable grips to keep weight on hoist
line and not on waveguide. Make certain to allow slack in waveguide when tying
and that slack is maintained during hoisting. tying is accomplished with strong
fiber-reinforced tape or similar material applied generously at 15 or 20 Ft. (4.6
or 6.1 m) intervals as waveguide is raised.
Hoist waveguide slowly. Careless handling can cause kinks, dents, and
scrapes. Waveguide may be bent in both E and H planes. Do not make bends