GB/T 28966-2012Cutter/bucket-wheel dredger supervisory control system (English PDF)

1 Scope

The standard lays down the requirements, the test methods, the inspection rules and the provisions on marking, packaging, transport and storage for the dredging supervisory control system of cutter suction and bucket-wheel dredgers.

It applies to the design, manufacture, refit and acceptance of such systems; the repair of a cutter/bucket-wheel dredger supervisory control system may also be carried out by reference to it.

2 Normative references

The list of normative references is headed by the usual sentence: for dated references only the edition cited applies, while for undated references the latest edition, including any amendments, applies.

Among the documents cited are GB/T 191 on pictorial marking for handling of goods, the GB/T 2423 series on environmental testing of electric and electronic products (low temperature, high temperature, damp heat, vibration, mould growth, salt mist, inclination and rolling), GB 4208 on degrees of protection provided by enclosures, GB/T 6587.8 on supply frequency and voltage tests for electronic measuring instruments, GB 11806 on the safe transport of radioactive material, GB/T 13384 on the packaging of mechanical and electrical products, GB/T 15479-1995 and GB/T 15511-1995 on industrial automation instruments and on marine electrical automation systems, GB 15702 on electronic chart specifications, the GB/T 17626 series on electromagnetic compatibility, GB/T 21671-2008 on acceptance testing of Ethernet local area networks, GBZ 135 on sealed gamma source containers, JTJ 203 on surveying for waterway engineering, and three China Classification Society rules: the rules for classification of sea-going steel ships, the construction rules for sea-going ships engaged in domestic voyages and the construction rules for steel inland waterway vessels.

3 Terms and definitions

3.1 cutter/bucket-wheel dredger supervisory control system (CDSCS): system that applies sensing, measurement, network, communication, computer and automation technology to monitor and control the dredging operation of a cutter suction or bucket-wheel dredger.

3.2 basic dredging supervisory control system: dredging supervisory control system with the minimum configuration that satisfies the dredging operation of a cutter/bucket-wheel dredger.

3.3 expanded dredging supervisory control system: dredging supervisory control system that, on the basis of the basic system, has functions extended as required.

3.4 automatic cut control (ACC): use of a computer and a programmable logic controller to carry out interlocked automatic control, according to a set logic, of ladder hoisting and lowering, of swing movement and swing speed, of spud changing and of carriage stepping, so as to achieve automatic cutting control of the cutter/bucket-wheel dredger.

3.5 automatic dredging control system (ADCS): system that automatically controls the equipment involved in the dredging operation of a cutter/bucket-wheel dredger.

3.6 dredging decision-making assistant system (DDAS): information processing system that applies means such as data mining and data fusion to perform dynamic integrated analysis of dredging construction data and to search for the optimum construction process parameters.

3.7 control network: computer network that implements the control functions of the dredging operation by means of standard network protocols.

3.8 administration network: computer network that implements the information enquiry and management functions of the dredging operation by means of standard network protocols.

3.9 machinery control and monitoring system (MCMS): system that controls and monitors the dredging machinery of a cutter/bucket-wheel dredger.

4 Abbreviations

AMS is the alarm and monitoring system; APC is automatic pump control; CCS is the China Classification Society; DTPM is the dredging tracking and profile monitor; HMI is human machinery interaction; PLC is the programmable logic controller.

5 Requirements

5.1.1 Classification. According to the complexity of the functions it performs and its technical level, a CDSCS is divided into a basic dredging supervisory control system and an expanded dredging supervisory control system.

5.1.2 Composition of the basic system. It shall include the machinery control and monitoring system (MCMS), the dredging tracking and profile monitor (DTPM), the alarm and monitoring system (AMS) and the dredging instruments.

5.1.3 Composition of the expanded system. Besides what 5.1.2 lists, it should include the automatic dredging control system (ADCS) and the dredging decision-making assistant system (DDAS).

5.1.4 Structure. A CDSCS should adopt a multi-layer interconnected network structure comprising a field device layer, a process supervisory layer and an information management layer; a basic system may also adopt a non-networked form; the control network and the administration network shall be isolated from each other; network and servers have at least one-to-one redundancy.

5.1.5 Operating modes. A CDSCS shall provide a manual control mode, using levers, push-buttons, knobs and the human machinery interaction (HMI); an automatic control mode; and an emergency control mode.

5.1.6 Software. The software shall satisfy GB 15702 and JTJ 203; the graphic colours of the HMI shall conform to Annex A.

5.1.7 Earthing. Earthing of the CDSCS shall satisfy the requirements of the China Classification Society rules for classification of sea-going steel ships.

5.1.8 Power supply. The CDSCS is fed from a main and a stand-by supply; it shall be provided with an uninterruptible power supply of a capacity that keeps it running normally for at least 30 min when both the main and the stand-by supply fail.

5.2.1 MCMS functions. The MCMS shall control and monitor the starting, stopping and speed regulation of the power units and drives; the starting, stopping, speed regulation, raising and lowering, advancing and retracting and paying out and hauling in of the cutter or bucket wheel, the ladder, the swing gear, the spuds and carriage, the three-cable positioning device and the anchor boom; the starting, stopping and speed regulation of the mud pump and the gland water pump; the starting, stopping and flow and pressure adjustment of the hydraulic system; the opening and closing of the vacuum relief valve and of the dredging gate valve; and the barge loading system.

5.2.2 DTPM functions. The DTPM shall allow design, input, editing and plotting of planned lines, electronic charts, trench profiles and hull shapes; coordinate transformation, projection computation and the related parameter settings for construction positioning worldwide; import and display of standard graphic data files; and monitoring of the dredger position, heading, swing speed, cutter or bucket-wheel position and cutter or bucket-wheel depth in plan view, in profile view and in digital form. The DTPM should also provide input, modelling and display of three-dimensional soil geographic information.

5.2.3 AMS functions. The AMS shall acquire, process, display and record the monitored alarm quantities in accordance with the relevant requirements of the China Classification Society rules cited in the standard, and shall allow alarm set points to be changed by means of an authorisation password.

5.2.4 ADCS functions. The ADCS should provide automatic cut control (ACC), automatic pump control (APC) and automatic control of the vacuum relief valve.

5.2.5 DDAS functions. The DDAS shall record, store and replay the data generated by monitoring and computation, produce statistical analysis reports, and perform intelligent optimum-seeking analysis of the excavation and transport construction parameters; it should also provide soil-based optimum-seeking analysis of the construction process parameters.

5.3 Performance. The network link transmission rate shall be not less than 2 Mbps for the control network and not less than 100 Mbps for the administration network. The monitoring points shall satisfy the intended use and leave a margin of not less than 20 %. The data display refresh interval shall be not more than 1 s and the data storage interval not more than 2 s. The storage medium shall hold 365 d of continuously recorded CDSCS data. For multi-point alarms, the response time of alarms bearing on ship safety shall satisfy the China Classification Society rules cited, while other alarms shall respond in not more than 6 s. The alarm system input/output points shall leave a margin of not less than 20 %. The control response time shall be not more than 0.5 s and the control system input/output points shall leave a margin of not less than 20 %.

5.3 Performance, accuracy figures. The mean error of the vessel plan position is +/-2.0 m and that of the vessel heading +/-0.3°. The maximum permissible error of the cutter or bucket-wheel lowering depth is +/-0.15 m and the mean error of its plan position +/-2.5 m. The maximum permissible error is +/-0.10 m for carriage travel and +/-0.05 m for trunnion draught. For flow velocity and for slurry density the maximum permissible error is +/-3.0 %, and for mud pump vacuum and pressure +/-1.0 %.

5.4 Appearance quality. The outer surfaces of the CDSCS equipment shall be free from scratches, rust spots, colour differences and burrs.

5.5 Environmental adaptability. Temperature, relative humidity, inclination and rolling and vibration shall satisfy 3.2.1, 3.2.2, 3.2.4 and 3.2.3 respectively of GB/T 15511-1995. After 56 d under the mould conditions listed in the standard, the mould growth grade shall be not higher than grade 2 of GB/T 2423.16-2008. Exposed metal parts, components and internal metal portions shall show no metallic corrosion products on the surface after 48 h under salt mist conditions.

5.6 Electromagnetic compatibility. The immunity of the CDSCS shall withstand severity level 3 of GB/T 17626.2-2006 for electrostatic discharge, of GB/T 17626.3-2006 for radiated radio-frequency electromagnetic fields, of GB/T 17626.4-2008 for electrical fast transient bursts and of GB/T 17626.5-2008 for surges, and shall withstand voltage dips of severity class 3 and short interruptions of severity class 2 of GB/T 17626.11-2008.

5.7 Enclosure protection. The degree of protection shall be IP68 for submerged equipment, IP56 for equipment exposed on and above deck, IP44 for equipment in the machinery and pump spaces and IP20 for console equipment; other equipment shall satisfy the relevant enclosure protection requirements of GB 4208.

5.8 to 5.10 Electrical requirements. The voltage and frequency of the supply shall satisfy the relevant requirements of 3.3 of GB/T 15511-1995; the insulation resistance shall satisfy 4.1 and the dielectric strength 4.2 of GB/T 15479-1995.

6 Test methods

6.1 Functions are tested in two steps. After all the programs of the CDSCS have been commissioned, the system is connected in the works to a simulation test bench and to simulators of the controlled equipment, and the functions required by 5.2 are simulated, tested and recorded. On board, the CDSCS is connected to the actual controlled equipment and, once the joint commissioning of the programs is finished, the functions are tested and recorded. The results shall conform to 5.2.

6.2 to 6.3 Performance is tested according to Annex B, with results conforming to 5.3; appearance is checked visually against 5.4.

6.4 to 6.9 Environmental tests. Temperature testing follows GB/T 2423.1 and GB/T 2423.2; relative humidity testing follows GB/T 2423.3 and GB/T 2423.4; inclination and rolling follow GB/T 2423.101; vibration follows GB/T 2423.10; mould growth follows GB/T 2423.16-2008. For salt mist, metal parts and components are tested according to GB/T 2423.17 and the complete equipment according to GB/T 2423.18.

6.10 Electromagnetic compatibility. Electrostatic discharge, electromagnetic field, electrical fast transient burst, surge, voltage dip and short interruption immunity tests are carried out according to GB/T 17626.2-2006, GB/T 17626.3-2006, GB/T 17626.4-2008, GB/T 17626.5-2008 and GB/T 17626.11-2008 respectively, with results conforming to 5.6.

6.11 to 6.14 Remaining tests. Enclosure protection is tested according to GB 4208; the voltage and frequency test of a.c. supplied equipment follows GB/T 6587.8; insulation resistance follows 5.3 and dielectric strength 5.4 of GB/T 15479-1995.