M83

M83
M83(October(cont)2023)

Testing of the control system of controllable
pitch propellers intended for main propulsion
1

PurposeThe purpose of the tests required by this UR is to ascertain that the pitch control system ofCP propellers for main propulsion is working correctly.
2Application

The requirements in this UR apply to all new buildings and to all replacements, modifications,repairs, or re-adjustments that may affect the pitch control or response characteristics formain propulsion.
3

Scope of the tests

3.1

Pitch response test

A full range of tests is to be carried out to get the pitch response and verify that it coincides
with the combinator curve of the propeller1. The tests are to be carried out for at least threepositions of the control lever in ahead and astern directions (e.g., dead slow ahead / astern,half ahead / astern, full ahead / astern).
The tests are to be carried out in normal and emergency operating conditions.
Tests that are not affected by the control position may be carried out from one control position
only.
Note1: The combinator curve is the relationship between the propeller pitch setting and thepropeller speed.
3.2

Test of the fail-to-safe characteristics

A test of the fail-to-safe characteristics of the propeller pitch control system is to be carriedout to demonstrate that failures in the pitch command and control or feedback signals arealarmed and do not cause any change of thrust. Such failures are to be clearly identified andincluded in the test procedure.
3.3

Test procedure

Test procedure is to be prepared and proposed by the pitch control system manufacturer or
integrator and agreed with Classification Society.
4Parameters to be recorded

The list of the parameters to be recorded during the pitch response test within this UR is to beestablished by the pitch control system manufacturer or integrator and agreed with theClassification Society. This should include at least the following parameters:- Position of the control handle,- Actual pitch indication (local indication, remote indications),

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M83

- Rotational speed of the propeller,(cont)- Response time between the pitch change order (modification of the lever position) andthe instant when the pitch and propeller speed have reached their final position,- Propelling thrust variation during the transfer of the control from one location toanother one.
5

Tests results

Tests are to demonstrate:- that the propelling thrust is not significantly altered when transferring control fromone location to another and in case of failures in the pitch command and control or
feedback signals.
- that the pitch response times measured during the test do not exceed the maximum
value to be defined by the pitch control system manufacturer or integrator.

Note:
1.

2.

This UR is to be uniformly implemented by IACS Societies on:(a)ships contracted for construction on or after 1 January 2025.

(b)

ships other than those specified in the preceding (a) on which astern testing iscarried out in accordance with Z18 on or after 1 January 2025.

The “contracted for construction” date means the date on which the contract to build thevessel is signed between the prospective owner and the shipbuilder. For further details
regarding the date of “contract for construction”, refer to IACS Procedural Requirement(PR) No. 29.

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IACS Req. 2023