SAE J1782 pdf download
SAE J1782 pdf download.(R) Ship Systems and Equipment—-Hydraulic Systems—Noise Control.
1. Hydraulic systems are used on marine vehicles for steering, vehicle control, and utility services. System components that generate and transmit noise are of concern. This SAE Information Report (a) addresses noise requirements which may apply to the hydraulic systems of ships and submersibles, and (b) identifies noise sources and techniques which may be used to reduce system noise. Noise of power sources (e.g., electric motors) and end items (e.g., steering linkages) is beyond the scope of this document.
1.1 Purpose—The purpose of this document is to summarize design information on how to reduce noise of On- board hydraulic systems.
1.2 Application—This document is applicable to the marine vehicles using hydraulic systems. This document does not apply to recreational watercrafl.
2. References
2.1 Applicable Publications—The latest issue of the referenced documents should be used. Nothing in this document supersedes applicable laws and regulations unless a specific exemption has been obtained,
2.1.1 INDUSTRY PUBLICATIONS—Industry publications that have been adopted by the Department of Defense (DoD) can be ordered by DoD activities only from 000SSP, Subscription Services Desk, Building 4D. 700 Robbins Avenue, Philadelphia. PA 19111-5094.
2.1.1.1 SAE Publications—Available from SAE. 400 Commonwealth Drive. Warrendale, PA 15096.0001 –
SAE Ji 778—Ship Systems and Equipment—Recommended Practice for Hydraulic Fluid Selection SAE AS5440—Hydraulic Systems, Aircraft. Design and Installation Requirements for
2.1.1.2 ASA Publications—Available from the Acoustical Society of America, Standards and Publications Fullillment Center, P.O. Box 1020, Sewickley. PA 15143.9998.
ASA 38—Guide for the Evaluation of Human Exposure to Whole-Body Vibration (ANSI S318)
ASA 47—Specification for Sound Level Meters (ANSI Si .4)
ASA 65—Specification for Octave. Half-Octave and Third-Octave Band Filter Sets (ANSI Si .11)
ASA 107—Guidelines for the Specification of Noise of New Machinery (ANSI Si 2.16)
ASA 111—Acoustical Terminology (ANSI Si .1)
4.2.1 COMMERCIAL SHIPS
42.1.1 IMO Racommendations—4M0 Resolution A.4684Xll) provides guidance to Administrations regarding acceptable noise levels. See IMO Resolution A.468(Xll) for scope of application. Examples of categories and noise limits are as follows:
Cabins, hospitals, and radio rooms (with radio equipment operating but not producing audio signals):
60 dB(A)
Navigating bridge, chartrooms, radar rooms, mess rooms, recreation rooms, and offices: 65 dB(A)
Listening post, including navigating bridge wings and windows: 70 dB(A)
Machinery control rooms, galleys without food processing equipment operating. servenes, pantries, and open recreation areas: 75 dB(A)
Workshops: 85 dB(A)
4.2.1.2 Surface Effect Ships (SESs)—For commercial SESs with displacements up to 145 LIons, hydraulic system noise is usually not significant compared to drive system noise.
4.2.1.3 Air Cushion Vehicles (ACVs)—For commercial ACVs with displacements up to 30 Ltons, hydraulic system noise is usually not significant compared to drive system noise.
4.2.2 UNITED STATES MILITARY REQUIREMENTS
4.2.2.1 Equipment Noise Limits—MlL-STD1474, Requirement 5 specifies equipment noise limits. These limits are specified in terms of Sound pressure level measured close enough to the machine as to minimize the eftect of the room in which the machine is tested. These limits are typically invoked for land-based (e.g.. pre-installation) testing rather than shipboard testing.
4.2.2.2 Compaitment and Space Noise Limits
4.2.2.2.1 Large Ships—For Navy ships and submarines over 150 ft in length or manned by 100 or more crewmembers, OPNAVINST 9640.1 specifies acceptable airborne noise levels. Older ships may have octaveband requirements In lieu of dB(A) requirements; newer ships may have requirements more stringent than OPNAVINST 9640.1.
4.2.2.2.2 Air Cushion Vehicles—Navy noise limits in the command module and personnel and equipment module are 92 dB(A) and 99 dB(A), respectively. Hydraulic system noise is usually not significant compared to drive or lift system noise.
4.2.3 NOISE EXPOSURE AND HEARING CONSERvATION—29 CFR 1910.95 is applicable to all ships operating under United States federal regulations. OPNAVINST 5100.19 is applicable to all United States Navy Ships. 29 CFR 1910.95 and OPNAVINST 5100.19 invoke, and IMO Resolution A.468(XLL) recommends, hearing conservation requirements for noise exposure, Harris’“Handbook of Noise Control” (2.1.3) addresses the effects of noise on speech, hearing loss, and physiology.
5. Hydraulic Noise Sources—Hydraulic system noise is typically dominated by pumps, motors driving the pumps, actuators, and fluid flow and cavitation. The main sources of noise should be identified first. A reduction of 3 dB results from reducing sound power level by 50%. lSO/TR 11688-1 and 11688-2 provide general guidance regarding the design of low-noise components.
