API 617 Standard

[CaracasEC]

Hi All,
I'm looking for a clause on the code specifying that the lube oil stand-by pump shall be automatically started. Hoping for your helps...Thanks a lot...

 

[Airsporter1st]

I think you need API614 - that might explain why you cannot find it in API617

I think the relevant clause is 4.2.15 in API 614 5th Edition which as I understand it, simply says that the vendor and purchaser have to agree what protection is required in the event of failure of the primary pump. If I interpret that correctly then this means that there is no such clause as you are looking for!!

Of cpourse, I've been wrong before:-(

 

[bcs5274]

unless you are talking of a standby lube system that keeps a set amount of oil psi on the unit so there is lube to all bearings all the time?

seen this on several compressor stations that keep oil psi and warm and circulate coolant so that when units are started remotely there is minimal warmup before being put on line.

 

[CaracasEC]

Thanks, API 617 simply states on lubrication and sealing system "Unless otherwise specified, pressurized oil system shall conform to the requirements of API Std. 614, Chapters 1 & 2. API 614 Basic design " The design shall allow for transfer between and shutdown of the main and spare components of the system for maintenance without interrupting the operation of the system or the equipment the system serves". API 614 Pumps and Driver "The oil system include a main oil pump and a standby oil pump. The main and standby pumps shall be identical and suitable for continuous operation". The start-up control of the standby pump shall be actuated by devicexs gthat sense low supply pressure to the equipment or low oil levels in the overhead seal oil tanks. However i cant find neither on the API 617 nor 614 that states that both the main lube oil pump or the standby lube oil pump shall be both designed on auto start-up mode.However, API 614 4th Edition page 96 on accumulators states that "The control pressure shall be maintained above the equipment manufacturers minimum specified, supply pressure at all operating conditions (including transient. What i understand with this clause is that whether the lube oil pump running is a motor or the turbine, accumulator design shall consider both case and that they shall be design both on auto start-up mode. Hoping for your comments...thanks

 

[Pumpsonly]

This thread is related to your another thread

Automatic Start-up of steam turbine driven lube oil pump

The whole purpose and function of the standby or back up LOP is to ensure the LO supply is not interrupted in the event of the main LOP failure. If it is not auto-started as soon as the LO pressure drop to the preset level, how fast do you think the operator can start it manually on the trigger of an low pressure alarm?

Auto starting of the main LOP, if applied is usually tie in to the permissive starting sequence of the main equipment.

 

[CaracasEC]

Hi Pumps only, thanks..Yes this is related to the other thread as you said. As Mr. JJpelin told that accumulator design will be more complicated. I am looking back to API 617 or 614 that have a clause that both will be auto-start-up however until now i cant find any...I hope you could help me any provision on the standard that will state that both pumps shall be design automatically started...

 

[Pumpsonly]

I don't have copy of 617 & 614 handy.
Use your logical thinking as an engineer. If the main pump also require to auto-start,what logic should be used to trigger the auto start?

You start the main L/O pump first to build up the oil pressure before you start up the compressor or turbine.Once started it will be kept running until manually stopped or tripped due to mechanical or power supply failure.
The stand-by L/O pump is usually powered by a different power source from the main pump.
If you have a turbine driven unit,it is always use as the main pump due to more complicate starting procedure than electric motor driven unit.

 

[CaracasEC]

Hi Pumps only, thanks for your enlightenment. How about a logic that will include the main oil pump that is turbine driven with a manual/auto. During start-up it will be switch on to manual and then it will be switch to auto operation? This will assure me during normal operation that both the lube oil pump will be flexible.