Hamilton Jet HJ212, Installation And Service Manual

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Installation and Service Manual
Design Basics
Engineering Checks
All component suppliers (including driveline, engine and jet suppliers) must be consulted with full driveline
details to ensure suitability and compatibility of components.
Checks must include:

Critical speed check for whirling of the jet unit mainshaft: Consult C.W.F. Hamilton & Co. Ltd.

Critical speed check for whirling of the driveshaft: Consult driveline supplier.

Engine to jet alignment: Consult C.W.F. Hamilton & Co. Ltd.

Torsional vibration analysis: Consult engine or torsionally flexible coupling supplier.
Critical speed checks should allow safe operation up to the engine's
no load
governor setting
(or high idle).
Driveline Options
Depending on the distance between the jet unit coupling flange and the engine, other driveline options may
be chosen. Longer drivelines would not normally be used on this jet. If they are under consideration, consult
Hamilton Jet whilst using the following sections as a guide.
Double universal fixed length driveshaft (Cardan shaft):

This is the usual type of driveshaft used. It bolts directly to the jet unit splined companion flange. The
driveshaft must not have any axial plunge as this is already accommodated by axial float between the
companion flange on the jet shaft spline.

An adaptor plate or alternatively a suitable torsionally flexible flywheel coupling (TFFC) can be used
between the universal driveshaft and the engine flywheel. The TFFC must be of the type with a support
bearing to support the universal driveshaft. "Vulcan", "Centa" and "Kusel" have suitable couplings for use
with universal driveshafts. Use of a TFFC is more appropriate for diesel engines and may be stipulated by
some manufacturers.

Length limitations are from approximately 650mm upwards but limited by the weight which can be
allowed at the coupling. Refer to drawing: HJ21202003 Couplings.
Universal Driveshaft Alignment
There are only two possible centerline locations for jet unit and gearbox.

'W' configuration

'Z' configuration
Universal driveshafts must be assembled with the yokes (forks) in the same plane.
The heavier splined end of the driveshaft should be installed at the gearbox end of the driveline.
Correct running length of the shaft is with the shaft extended to half the total spline extension length.
When the TFC couples directly to a universal driveshaft, the TFC must provide a bearing to support the
universal driveshaft.
When the TFC couples directly to a lineshaft supported on bearings, a support bearing is not required.
The engine must be positioned so that the universal joints of the driveshaft have equal offset
angles. This is most important.
Refer to the driveshaft manufacturers recommendations for joint angles (typical range is
between 1.5 and 5degrees).
3-5