Driving Straddle Carriers

[hilifta]

Hi,

Since I posted a couple of photos of our (Auckland) straddle carriers some members have asked about them.
We forget that most people have no idea about them as we just take them for granted.
In Auckland we have just changed from our old Finnish Valmet/Sisu machines the the new German Noells at $1.6 million dollars each.
They are light years apart, it's amazing how 10/12 years have changed a machine.
The old machines had two diesel 6 cyl in line Volvo engines. Mounted one on each side just above the wheels.
The new machines are diesel electric. Originally they had V10 Mercs but the vibration caused the Company to change to V8 Cats, this drives an electric motor both of which are mounted up top.
The difference in stability is quite noticable.
The driver position is about 10 metres high. The machine will lift up to 3 boxes high. This means we can go over a 2 high stack if we are carrying a box, or over 3 high boxes if we are empty.
All 8 wheels steer, and the inner 4 are driving wheels. The machine are extremely manueverable and it is quite astounding the gaps we can squeese into.
The driver sits sideways to the direction of travel. The reason for this is we go in either direction, (cab first and legs first) and it is the practical way to do it.
The steering is back to front, which does take some getting used.
Training last for 3/4 weeks and obviously a huge empasise is put on safety. They do after all weigh 61 tonnes empty and can carry up to 50 tonnes. Beleive me you can feel it when you are that heavy. The machines talk to you.
They have to be respected.
As for experience, I only had a car license, but I admit I did have some trouble getting used to it. When you have a 40ft box 3 high and you are travelling "legs first" (that is cab to the rear) your visibility is severely restricted.
We are governed by marks on the legs and marks on the bumper bar in front of the cab to tell us where we are and where the box is. Because of the height you sit, you simply cannot rely on your eyesight, if you did you'd bang into every box and truck there was. A thing called parallax error comes into play here.
The marks on the bumper tell when we are centred when driving down rows of containers. We sight the spreader with the edge of the containers and then look to see where the mark is. After that we just sight the mark in that position with the knowledge that we wont hit anything. (Thats the theory anyway)
Loading trucks is a real pain in the ****. I have to say, that truckies aren't the brightest boys around. They should stand in a certain position when we load them, but they wander everywhere. They think that because we are up high that we can see everything. They just don't realise the blind spots we have. Then they get shirty when we tell then they can't squat down and polish their wheels. If they do that we just cannot see them.
No one should be in the cabs, but in school holidays they hide their kids in there!!
Then they don't put flouro paint on the pins. This makes our job so much easier, especially at night. If it dark and/or raining, its a high swinglift, and its painted dark blue, its like dropping a box down a coalmine. And if you miss the pins they start waving their arms and fingers around.
Great stuff.
We do have our laughs though, heres a couple, all happened before I started.
A straddle hit one of the huge light towers one day and half pie climbed up it. Well slowly the weight of the straddle pushed the light tower over. What a mess, well into 6 figures damage.
One a driver, end of shift, a bit tired, forgot he had a 40ftr on and lined up on the 20ft pins on the trailer, and then lowered the box on top of the cab.
Oh dear, luckily it was only an old Japper, but it did look funny to see the driver driving off with the roof only about 1ft above the bottom of the window.
Never saw that truck again.
But the best one was a small 2 axle truck that turned up with an mty 20ftr on.
Drivers are supposed to have unlocked the box at the office b4 stopping on the grid. The truckie then went to log in his card, the straddle driver came over the truck legs first, latched on, and lifted the box. He then just flicked the straddle into gear and took off.
Well an mty 20ftr only weighs 2tonne, and a 2 axle truck about 8 tonne, all up 10 tonne, nothing for a straddle.
Off he went container up high, and truck hanging beneath it, and a driver frantically running after it waving his arms!!!.
Guys who saw it happen just couldn't talk, they had tears of laughter rolling down their faces.

So there you have, the life and times of a straddle driver.

All the best,
Rgds/Mike (hilifta)

[Western SMT]

Interesting article hilifta and this ‘parallax error’ seems to be the same as a vehicle passenger looking at a needle type speedometer placed in front of the driver – they don’t see the same thing as the driver does.

[G-CPTN]

Many thanks for that, hilifta.
Although some of us are experienced with trucks and haulage, some have never been inside a container depot and so haven't seen guys like you doing what you do day in and day out.
Many of us are interested in all mechanical machines so to learn something about your 'vehicles' is welcome knowledge.

Do you only ever carry one container (and the occasional truck!) at any time?

What does the crane pick up on? Does it use the corner lock sockets?

Seems like straddle-cranes have been around for almost a century:-
http://www.scientificamericanpast.co.../sci271920.htm

[hilifta]

With the spreader closed we can carry 1x20ft container, extended we can carry 1x40ft, or by dropping centre pins we can carry 2x20ft boxes.
If a truck trailer is configured correctly we can lift 2x20ft boxes off a truck at once. Often though trailers aren't suitable for this.

If you look at a container you see in the corners, top and bottom there are whats called "corner castings". On a truck the bottom ones are locked on to the truck by his twistlocks. A straddle and the container cranes use exactly the same method in the top castings.
Likewise on the ships, a thing called a super twistlock is used to lock the boxes together.
These, together with lashing bars, are all that hold the boxes secure to the ship.
To unlock them so they can be discharged a toggle is pulled by a lasher on the ship, and this unlocks the bottom box. The crane then lifts it off and a lasher on the berth then removes it from the box before a straddle then takes it to a stack.

Hope this helps.

Rgds/Mike (hilifta)

[G-CPTN]

I can understand all that you have written (including the parallax 'problem', and I can appreciate that you can align the container with the trailer (side to side), but how do you line up the sockets with the twistlocks (fore and aft)?

[hilifta]

Hi GC,

When we go over a box, for a 20ftr we line up on the spreader guides (these are the things the spreader slides up and down on)and if done correctly the twistlocks drop straight into the castings.
For a 40ftr, because it extends under the cab we can just look straight down on it and then just use the Mk 1 eyeball.

Mike

[G-CPTN]

Thanks for that.

[billyboy]

Many thanks for this article Hi Lifta. very informative.

[coastie]

Yes indeed! I'm still laughing at that image of the container and truck being lifted in the air.

[G-CPTN]

http://www.eurans.com.ua/eng/faq/portcontainermoving/