燃油供给问题（Black out时发电机启动）

heliangjimei

各位朋友，关于标题，请教如下问题：
      背景：船级社要求船舶在Black Out状况下，备用发电机能够自动启动（通常要求时间是30秒内，如:GL），这就要求相应的油、水、气具备相应的条件，冷却水短时间内的影响不考虑，滑油短时间内的影响也不考虑，且启动空气在该状况下是满足的，唯一存在疑点的是燃油供给。查阅了几大船级社后，仅GL对燃油供给有明确规定，而其他船级社都只基本要求能够在black out状态下在规定是时间内自定启动即可，暂时未查到相关具体的描述。
引自GL规范：I-1-2-G4.4；
（G.4.4 Where a feed or booster pump is required to supply fuel to main or auxiliary engines, stand-by
pumps are to be provided. Where pumps are attached to the engines, stand-by pumps may be dispensed
with for auxiliary engines.
Fuel supply units of auxiliary diesel engine are to be designed such that the auxiliary engines start without
aid from the emergency generator within 30 sec after black-out.
Note
To fulfil the above requirements for example the following measures could be a possibility:
 Air driven MDO service pump
 MDO gravity tank
 Buffer tank before each auxiliary diesel engine）
据以前接触过的供油单元，仅ALFALAVAL和GEA Westfalia在供油单元中有Buffer tank或者Air driven Pump的设置，其他供油单元没有相关的设置（我也没有使用过这些厂家的设备）。
      备注：目前使用的是YAMAR发电机，船级社：ABS。
      个人观点：供油系统（供油单元）在不具备上述装置时，备用发电机在Black Out状况下自动启动是能够实现的，只是此时燃油供油压力不高，效果不理想，GL有上述要求是为了更好的保证供油压力，提高此时的可靠性。（因目前没有做过供油单元没有上述装置的燃油系统，其个人观点仅供参考，还希望大家多指教。）
      问题：如供油系统上没有上述设置，在Black Out的状况下是否能够正常供油，备用发电机是否能满足启动要求？

labilaoxin

如果没有上述装置，供油单元如何供油？

heliangjimei

labilaoxin 发表于 2016-9-22 16:19
如果没有上述装置，供油单元如何供油？

在Black out发生前，供油单元是正常运行的，供油单元和发电机之间的管内是有正常压力的燃油的；Black out 发生时，供油单元停止运行，但因其单元内供油管路上有止回阀，因此短暂时间内是有燃油的，其压力就比较低，非正常压力。

文武后人

使用主发电机组作为黑启动用，船规中已明确告诉你有3章方式：
1.气动燃油泵（MDO）
2.高置重力油箱（MDO）
3. 供油单元混油桶（MDO、HFO均可，压缩空气保持压力）。
以前做船舶设计时这3种方式恰好都使用过。
其它的方法还真没见过。

heliangjimei

文武后人 发表于 2016-9-22 18:10
使用主发电机组作为黑启动用，船规中已明确告诉你有3章方式：
1.气动燃油泵（MDO）
2.高置重力油箱（MDO ...

问题可能有点不准确，不应问是否能正常供油，而是供油单元至发电机间管路内的燃油是否能满足备用发电机的正常启动？我所经历的不多，基本都是采用带蓄能器的方式，现在接触的一款国产的，没有任何东西，所以心是悬着的。

江海直达

这种配置应该是德劳规范的特别之处。其它船级社认可依赖应急电源的柴油泵。我所说应急柴油泵，应是配置为瘫船启动使用。
而失电瞬间，备用发电机启动用油，看你供油系统的设计，若油柜高过高压油泵的吸口，就没问题，如是依赖燃油供油单元，混油柜中的储备的油和管路中的剩油足够发电机组启动并维持到供油泵再次启动，供油泵顺序启动时间数秒而已。

参照16楼，再判断！

heliangjimei

江海直达 发表于 2016-9-22 22:07
这种配置应该是德劳规范的特别之处。其它船级社认可依赖应急电源的柴油泵。

我也是很赞同可能是德国人做事更严谨，所以有此特别说明相应的措施。按“江师傅”您的意思，此时必须要先有应急电源过来才行，时间上可能就会延长。据您所知，Black out到恢复主配电板供电需要多久时间呀？

labilaoxin

heliangjimei 发表于 2016-9-22 22:32
我也是很赞同可能是德国人做事更严谨，所以有此特别说明相应的措施。按“江师傅”您的意思，此时必须要先 ...

江老师是说从应急供电的是为了瘫船启动用。对于black out的情况，江老师说如果油柜位置较高或者混油桶管路的油可以使备机启动
但好像在black out的情况下，并没有强制规定备用机必须启动，只要你在45秒能恢复供电就应该满足要求，而GL的30秒应该只是推荐

ndlxz

在进机前做一n型管,这点重力油足够了

qcsheng

别忘了还有应发

文武后人

black out 情况下主发应急启动船规中没有明确要求，一般都是船舶的大规格书中的规定。
如果没有气动燃油泵（MDO）、高置重力油箱（MDO）、 供油单元混油桶。管路中的燃油是否可以满足发电机组启动，这个真没有经验。一般情况下供油单元混油桶中的燃油可以满足单台发电机组运行10~15分钟。
假如使用管路中的燃油启动，可以分析下，发电机组启动过程及需要时间如下：
发出起动指令------柴油开始起动--------转速建立（同时给PMS信号）------转速稳定-----滑油压力建立（系带滑油泵）。算是柴油机起动成功了。整个过程大概需要25S。这个完成之后，还需要、控制柜各种电动泵的供电及启动时间。
从分析上看管路中的油是不够的。
但是也没有实践过。

heliangjimei

labilaoxin 发表于 2016-9-23 08:21
江老师是说从应急供电的是为了瘫船启动用。对于black out的情况，江老师说如果油柜位置较高或者混油桶管 ...

下面是ABS对Dead ship 和Black out两种状态的定义，其基本意思和其他船级社的定义没有大的区别：

1.9.6 Dead Ship Condition (2004)
Dead ship condition means a condition under which:
i) The main propulsion plant, boilers and auxiliary machinery are not in operation due to the loss of the main source of electrical power, and
ii) In restoring propulsion, the stored energy for starting the propulsion plant, the main source of electrical power and other essential auxiliary machinery is assumed to not be available.
1.9.7 Blackout (2004)
Blackout situation means the loss of the main source of electrical power resulting in the main and auxiliary machinery to be out of operation


瘫船状态的电源恢复目前没有疑问，主要是在Black out状态下的主电源恢复，首先是应急电源供电给供油单元，然后启动发电机，这个过程的时间在45s内是否能够实现？（能否提供个这样设计的完工的项目参考下呢？）其次备用发电机在个时候不自动启动，总感觉功能就少了似的，同时上一个项目GL确实是要求备用发电机此时起来，所有有这个思维。

labilaoxin

heliangjimei 发表于 2016-9-23 11:06
下面是ABS对Dead ship 和Black out两种状态的定义，其基本意思和其他船级社的定义没有大的区别：

1.9. ...

45S必须恢复供电，这个是毫无疑问的。至于black out 后是否启动备机，大部分船能够实现
但好像（不确定）规范没有强制要求必须先启动备机。于是可以这样理解
当应发启动后，应配给供油单元供电，这样启动备机就没有任何障碍了

江海直达

heliangjimei 发表于 2016-9-22 22:32
我也是很赞同可能是德国人做事更严谨，所以有此特别说明相应的措施。按“江师傅”您的意思，此时必须要先 ...

你得仔细推敲它们规范的目的所在。
它们规范说，在三十秒内，重新启动任何一台处于备用状态的发电机组，这个时候，不要依赖应急电源，而实际上，失掉主电源的头三十秒，应急发电机还没完成启动和接入电网，因此它们规范要求三十秒内要实现启动备机，油路可以是气动泵或高位置油柜或缓充油柜。
但是它们规范，超越了solas的要求，其要求主电源掉电后，若是安装了自动启动的应急发电机组，应在四十五秒内实现启动和接入供电。
参照16楼，再判断！

heliangjimei

江海直达 发表于 2016-9-23 21:25
你得仔细推敲它们规范的目的所在。
它们规范说，在三十秒内，重新启动任何一台处于备用状态的发电机组， ...

基于目前设备的配置状况，也只能是应急电源先供给给柴油泵，然后启动备用发电机，时间保证在45s内。

ABS要求的是在一台发电机运行突然失电后，备用发电机最好是在30s内起来，但不允许超过45s，下面是详情；可供大家参考！

3.11.2 Single Generator Operation (2004)
Where the electrical power is normally supplied by a single generator, provision is to be made upon loss of power for automatic starting and connecting to the main switchboard of a standby generator(s) of sufficient capacity with automatic restarting of the essential auxiliaries in sequential operation, if necessary, to permit propulsion and steering and to ensure the safety of the vessel. Starting and connection to the main switchboard of the standby generator is to be preferably within 30 seconds after loss of the electrical power supply but in no case in more than 45 seconds.

江海直达

heliangjimei 发表于 2016-9-24 08:50
基于目前设备的配置状况，也只能是应急电源先供给给柴油泵，然后启动备用发电机，时间保证在45s内。

A ...

事情越探讨，越是明了：见以下法规对无人机舱的要求：

其实， 德老的要求，是对法规的细化：

Regulation 53 - Special requirements for machinery, boiler and electrical installations

1. The special requirements for the machinery, boiler and electrical installations shall be to the satisfaction of the Administration and shall include at least the requirements of this regulation.

2. The main source of electrical power shall comply with the following:

2.1. Where the electrical power can normally be supplied by one generator, suitable load-shedding arrangements shall be provided to ensure the integrity of supplies to services required for propulsion and steering as well as the safety of the ship. In the case of loss of the generator in operation, adequate provision shall be made for automatic starting and connecting to the main switchboard of a stand-by generator of sufficient capacity to permit propulsion and steering and to ensure the safety of the ship with automatic restarting of the essential auxiliaries including, where necessary, sequential operations. The Administration may dispense with this requirement for a ship of less than 1,600 gross tonnage, if it is considered impracticable.

2.2. If the electrical power is normally supplied by more than one generator simultaneously in parallel operation, provision shall be made, for instance by load shedding, to ensure that, in case of loss of one of these generating sets, the remaining ones are kept in operation without overload to permit propulsion and steering, and to ensure the safety of the ship.

3. Where stand-by machines are required for other auxiliary machinery essential to propulsion, automatic change-over devices shall be provided.

江海直达

江海直达 发表于 2016-9-24 11:06
事情越探讨，越是明了：见以下法规对无人机舱的要求：其实， 德老的要求，是对法规的细化： Regulation  ...

再比队16楼，就明了：

3. The emergency source of electrical power may be either a generator or an accumulator battery, which shall comply with the following:

3.1. Where the emergency source of electrical power is a generator, it shall be:

.1. driven by a suitable prime mover with an independent supply of fuel, having a flashpoint (closed cup test) of not less than 43°C;

.2. started automatically upon failure of the main source of electrical power supply unless a transitional source of emergency electrical power in accordance with paragraph 3.1.3 is provided; where the emergency generator is automatically started, it shall be automatically connected to the emergency switchboard; those services referred to in paragraph 4 shall then be connected automatically to the emergency generator; and unless a second independent means of starting the emergency generator is provided the single source of stored energy shall be protected to preclude its complete depletion by the automatic starting system; and

.3. provided with a transitional source of emergency electrical power as specified in paragraph 4 unless an emergency generator is provided capable both of supplying the services mentioned in that paragraph and of being automatically started and supplying the required load as quickly as is safe and practicable subject to a maximum of 45 s.

3.2. Where the emergency source of electrical power is an accumulator battery it shall be capable of:

.1. carrying the emergency electrical load without recharging while maintaining the voltage of the battery throughout the discharge period within 12% above or below its nominal voltage;

.2. automatically connecting to the emergency switchboard in the event of failure of the main source of electrical power; and

.3. immediately supplying at least those services specified in paragraph 4.

3.3. The following provision in paragraph 3.1.2 shall not apply to ships constructed on or after 1 October 1994:

Unless a second independent means of starting the emergency generating set is provided, the single source of stored energy shall be protected to preclude its complete depletion by the automatic starting system.

3.4. For ships constructed on or after 1 July 1998, where electrical power is necessary to restore propulsion, the capacity shall be sufficient to restore propulsion to the ship in conjunction with other machinery, as appropriate, from a dead ship condition within 30 min after blackout.

江海直达

这里德劳将，loss of generator in operation, 通过英语翻译成德语，又翻译成英文，造成了意思扭曲。loss of generator in operation 不同于 blackout
black out 应等同于 in case loss of main source of electrical power!

qianpeng32

不谈规范我来谈谈我在实际试验过程中遇到的问题，瘫船回复试验完全成功 而失复电在柴油模式下也全部成功 但是在试航时转到燃油模式再次试验失复电时出现 发电机在规范时间内启动但是不能达到合闸频率就闷车了 我的判断是燃油供给不足导致发电机不能持续运行到供油单元正常运转 目前正在尝试通过增加蓄能罐或者高位存放柜来解决 失电时的短时供油问题，后续解决了 我会更新回复的， 不管船级社要求与否我觉着很有必要确保燃油模式下断电后有足够的燃油储备支撑到供油单元正常运行。

heliangjimei

qianpeng32 发表于 2016-9-26 22:12
不谈规范我来谈谈我在实际试验过程中遇到的问题，瘫船回复试验完全成功 而失复电在柴油模式下也全部成功 但 ...

静待好消息！