Marine Engine Gearbox For Marine Engine NT-855-M240 Electrical
Remote Control Light & High-Speed Marine Gearboxes
Specifications:
Engine speed: 1000~2600 RPM |
Ratio |
1.03 |
1.25 |
1.50 |
2.03 |
2.48 |
2.95 |
Rate(hp/rpm) |
0.15 |
0.133 |
L×WXH: 504×619×616mm Net weight: 240 kg |
Bell housing:SAE 1,2,3 Flange: SAE 11.5,14 Options/Comments: Mechanical or electrical remote control Centre distance: 165 mm Recommend engine:NT-855-M240,CAT3406… Rated propeller thrust: 25KN |
Details:
HCQ138 marine gearbox has the functions of inverting, forwarding,
clutching, decelerating, and bearing the thrust of the propeller.
The gearbox is a vertical heterocentric one-stage transmission
structure, which has the characteristics of small size and
lightweight.
Causes and treatment of common failures of gearboxes:
1. Abnormal sound of gearbox
There are bumps on the gear tooth surface causing noise
Situation: This problem is mainly reflected in the testbed of the
assembly plant of the complete machine manufacturer. The
characteristics of this abnormal sound: the frequency of the sound
is stable, there is abnormal sound in one direction, and there is
no abnormal sound in reverse rotation. The speed and abnormal sound
of the low-speed shaft can be calculated The frequency relationship
of the noise to determine the specific location of the abnormal
noise.
Reason: bumps occurred during the assembly process. Due to the
company's flaws in the quality control of the test, a very small
number of gearboxes may have such problems.
Treatment: According to the analysis results, carefully look for
the bumps on the tooth surface of the relevant gear. When
searching, wipe off the oil on the tooth surface to avoid affecting
the feel. Bruises mainly exist on the tooth top and both sides of
the tooth profile.
2. The gearbox oil temperature is too high
The two outlets of the filter are respectively marked to the
gearbox or to the cooler. When the temperature is low, it directly
enters the oil distributor, and when the temperature is high, it
enters the cooler. If the oil pipes are connected reversely, the
high-temperature oil will not be cooled by the cooler, which will
inevitably cause excessive oil temperature. It can be solved by
installing the tubing according to the correct requirements.
3. The high-speed shaft bearing temperature is too high
The operation of the bearing must ensure a certain radial
clearance. When the clearance is too small, the rollers and
raceways will become suffocated, and a lot of heat will cause the
temperature to rise. This situation is relatively rare, you can use
a feeler gauge to detect the radial clearance of the upper end of
the bearing.
