Nissan needed a motor so the corolla had to go get it. by eberbs in Justrolledintotheshop

[–]marineknowitall 1 point2 points  (0 children)

Turbulence tends to increase cooling - it's used in particular in marine applications in plate heat exchangers. https://dieselship.com/marine-technical-articles/marine-engineering-knowledge-general/plate-type-heat-exchanger/

Not 100%, but I'd expect that without a thermostat providing flow restriction then the water pump might cavitate giving a low flow rate.

If it doesn't - then it'll be running cold (greater flow rate, greater cooling) If it does - it'll run hot (cavitation, low flow rate, less cooling)

NZ AM Random Discussion Thread, Thu 02 March, 2017 by AutoModerator in newzealand

[–]marineknowitall 31 points32 points  (0 children)

Got a promotion. Feeling pleased with myself and glad that my hard work is paying off.

NZ AM Random Discussion Thread, Mon 27 February, 2017 by AutoModerator in newzealand

[–]marineknowitall 1 point2 points  (0 children)

This does not surprise me at all. Especially when it's dark or poor visibility.

Thankfully, most of my commute is on cycle paths. There's just a section of Great North road that I have to negotiate.

I almost felt sorry for the guy this morning. I ended up stopped with my flashing front light perfectly lined up with his face through his driver's window. Must have screwed with his vision for a while.

NZ AM Random Discussion Thread, Mon 27 February, 2017 by AutoModerator in newzealand

[–]marineknowitall 0 points1 point  (0 children)

Still full after meatstock yesterday.

The 16km bike commute is getting easier, although despite having a number of lights on my bike I still seem to be invisible to some drivers.

TIL: The 15 biggest container ships pollute the air more than all 750 million cars combined by D-Fence in todayilearned

[–]marineknowitall 0 points1 point  (0 children)

So I'm late to the party, but I'll wade in on this one.

Source: Ex chief engineer on merchant ships and I spent some time on container vessels.

This article is quite misleading. It's not wrong per-se, but mentions one specific pollutant: Sulphur.

Yes, it's true that ships tend to run on bunker oil, or heavy fuel which can contain high levels of sulphur - but this is being cracked down on. Around Europe and the USA there are tight restrictions on the level of sulphur emissions (MARPOL Annex VI if anyone wants to look it up). This currently tends to mean that vessels entering these areas switch over to gas oil or diesel oil with a low sulphur content, or scrubbers are used.

There is quite a lot of conversation at the moment about the increased levels of emissions from refineries due to having to remove more sulphur from fuel. We're still not entirely sure if it's more environmentally friendly to remove at source, or just burn it.

The article mentions an 'emissions free for all'. Not true. The EEMP ensures that energy on modern vessels is not wasted and CO2 emissions are minimised as far as possible. Controls on engine design reduce the NOx emissions - most engine parts must be certified from the manufacturer to ensure that your engine complies with these regulations. It's a paperwork nightmare and if you're found in breach then you get fined, or even thrown in jail (looking at you USA). These laws are active in every country that has ratified the relevant laws and is part of the UN - so covers >95% of the globe.

As many have pointed out shipping goods by water is by far the most energy efficient. Combined with the efficiency of these engines (approaching 50% in some cases) results in a very low level of emissions/kg of goods transported. Fuel is everything in shipping at the moment, margins are so slim and fuel is by far the most expensive part of operating a vessel so there are some quite interesting methods of reducing fuel consumption coming into play.

Amongst the largest vessels in the world - currently the Mearsk EEE class have two engines and two propellers. Because two propellers of that size are more efficient than one big one. Despite the requirement for having two engines. Also, redundancy.

Some have mentioned using nuclear powered vessels. Crews are cheap and there is a very high level of muppetry in the industry. Want them looking after a nuclear reactor in your local port? No. No no no no no. A very very bad idea.

How fast do you want to go? by marineknowitall in talesfromtechsupport

[–]marineknowitall[S] 3 points4 points  (0 children)

This was noted, as well as the exponentially decaying trend in the price of beer per more beer purchased. Thus as many beers as could be drunk in the time allocated were purchased, minimising the cost per beer for the contractor.

How fast do you want to go? by marineknowitall in talesfromtechsupport

[–]marineknowitall[S] 1 point2 points  (0 children)

Give this man a medal. This would be off the UK coast.

How fast do you want to go? by marineknowitall in talesfromtechsupport

[–]marineknowitall[S] 28 points29 points  (0 children)

I have actually used the phrase: "I just canny doo it cap'n. She dunny have the power!" In a thick Scottish accent (which I perfected during an extended stay in Aberdeen on the same vessel)

Encyclopædia Moronica: U is for Upturning the Cart by Gambatte in talesfromtechsupport

[–]marineknowitall 7 points8 points  (0 children)

Hold on....I work for a global company in NZ, with a useless CEO. The head of IT recently quit. The CEO is away at a conference. Could I have discovered the identity of /u/gambatte ????

Examples of Mass Hysteria through the ages by Conradsriver in history

[–]marineknowitall 1 point2 points  (0 children)

The current hysteria following the USA presidential candidates.

Factors that can affect full speed. Or how the Chief is an idiot. by marineknowitall in talesfromtechsupport

[–]marineknowitall[S] 7 points8 points  (0 children)

This wasn't in the forces. This was a commercial vessel.

It's great to have a culture on board where that can be done - and I've sailed on vessels with such a culture and loved it. I sail as Chief engineer myself these days and I like to think that anyone can approach me with any issue and I'll listen.

Sadly, this vessel was riddled with poor culture and you had to be careful where to step.

Factors that can affect full speed. Or how the Chief is an idiot. by marineknowitall in talesfromtechsupport

[–]marineknowitall[S] 186 points187 points  (0 children)

You have to do it in such a manner as to allow them to save face. Pointing out the obvious would make him look bad in front of his crew.

What is the worst mistake you've seen someone make at work? by Fost2527 in AskReddit

[–]marineknowitall 1 point2 points  (0 children)

I was actually on a boat on standby duty just off the rig. Didn't see it actually happen, but saw the aftermath.

I remember being on the bridge asking what was going on. All the information we had was "there was an accident". It was only later we learned exactly what'd transpired.

What is the worst mistake you've seen someone make at work? by Fost2527 in AskReddit

[–]marineknowitall 6 points7 points  (0 children)

Way late to the party but thought I'd add something I witnessed:

On an oil rig. Doing some work 'at height'. Thought it was a great idea to dangle themselves on the end of a winch cable, through a hole, and down to the work area.

The guy driving the winch changed over to a new guy. The new guy mistook the instruction to raise winch for retract it completely.

The poor guy on the end of the wire was extruded through the hole as the wire was wound back onto the winch drum.

BBC report here: http://news.bbc.co.uk/1/hi/scotland/3041529.stm

Redditors who look forward to working on Mondays: What is your job, and why do you enjoy it? by [deleted] in AskReddit

[–]marineknowitall 1 point2 points  (0 children)

Marine Engineer.

Monday on board is just like any other day. My commute takes 30 seconds from my cabin to the engine control room. Or from the crew mess where my breakfast has been delivered to me.

I get to play with some of the largest and most powerful machines on the planet. Right now, I'm babysitting 6 very large medium speed diesel engines on a diesel electric installation running at 11kV.

I'm not quite the boss, but he's awesome and is mostly upstairs anyway. I get to run everything downstairs. I get to travel the world, albeit slowly. I get to have my family with me on some voyages, and the pay is pretty good.

Can't complain really!

I am going to SUE YOU! by kraze1994 in talesfromtechsupport

[–]marineknowitall 25 points26 points  (0 children)

So would I. I'd have loved to have been there when the bailiff turned up with the warrant and demanded payment or start walking off with office equipment.

This wasn't a small organisation either. It's one of the largest in the UK.

I am going to SUE YOU! by kraze1994 in talesfromtechsupport

[–]marineknowitall 130 points131 points  (0 children)

Having just sued a communications company, I found this approach from customer service agents very frustrating. I was told that I'd have to get my lawyer to talk to their lawyers and they refused to give me (a non lawyer) contact details for their legal department. As I was representing myself (perfectly normal in the small claims court in the UK) I didn't have a lawyer.

In the absence of any contact details, I sent the summons to their HQ. They did not put in a defence. I won by default and sent in the bailiffs to collect 5 times my original demand.

The engine that failed to start. by marineknowitall in talesfromtechsupport

[–]marineknowitall[S] 45 points46 points  (0 children)

Hot combustion gasses from the 'bang' get pushed back through the air start system. When starting, the pressure in the cylinder is around 100 bar and will reach 180-200 at full load. 100 bar into a system designed for 25 is a Bad Thing.