Book Review: Donald Duck A Muddy Fine Business; Artistic Equipment Design

Front page of Penny Pincher magazine with Donald Duck as dredge master (Credit: Disney)
Front page of Penny Pincher magazine with Donald Duck as dredge master (Credit: Disney)

Donald Duck is a Jack of all trades, that he eventually he would end up on a dredge was inevitable. The story was already published in 1977 in a Donald Duck comic magazine. It is written by Freddy Milton1 and drawn by Daan Jippes2. At that time, I read it and already liked it very much. Later, I had it in a comic album3, but lost it moving to a new house. I wanted to review this story here already for a long time. Eventually, I consulted ‘Bul Super’ in Delft4, he advised me to search for Daan Jippes. That helped to find the story back on the internet.5

Opening scene of ‘Muddy Fine Business’ or ‘Success Test’ (Credit: Disney)
Opening scene of ‘Muddy Fine Business’ or ‘Success Test’ (Credit: Disney)

The story revolves around the endless feud between Donald Duck and Gladstone Gander. This time they have to compete in a success test by operating two different vessels: a ferry, ‘Seagull’ and a dredge ‘Aristoteles’. They have varying degrees of success and the outcome is unexpected.

The best known illustrator of Donald Duck is Carl Barks6. But Daan grew into his footsteps and eventually his stories are at the same level as the original master. He was with the Disney studios in the USA, but was working mostly in the Netherlands. In this edition, Jippes drew one of the most Dutch professions: dredging. Jippes had a keen eye for the elements that make up a dredge, tough the execution lacks some reality. Here I want to highlight some shortcomings that will help to illustrate the tricks that should have made it work and explain how real life dredging equipment functions.

Various details of the ‘Aristoteles’ (Modified from Disney)
Various details of the ‘Aristoteles’ (Modified from Disney)

The ‘Aristoteles’ is a truly multi-functional dredging vessel. It features both a grab and a bucket chain and the sediment can be loaded unto the vessel itself like a hopper or into a barge in tow. It is also self-propelled, although there seems to be a magical power generation as there is no visible exhaust pipe. Maybe Donald is again ahead of his time and running fully electric already?

Than the dredging equipment; the grab is suspended from a gantry, but it does not seem to be able to swing. Loading the tow barge would be difficult, as he has to reposition either the dredge or the barge. Apparently Donald should know about the technology of a rotating crane, as the picture on the front page has such a crane. And how would the material end up in the hopper?

Discharging buckets with reception carriage on a bucket ladder dredge
Discharging buckets with reception carriage on a bucket ladder dredge

Maybe with the other dredging tool: the obvious bucket chain? Though it is not supported on a ladder. Maybe that makes sense, as the buckets seem to be positioned on port or starboard in various panels. The material falling from the buckets might end up in the hopper. The vertical orientation presents some difficulty, as the material will fall onto the previous bucket and eventually through the well. In a normal operation, this is controlled by moving a carriage receiving the load and bringing it to the chutes. With a real vertical orientation, this would not be helpful anymore.

I once saw a solution for working with a vertical bucket chain on an exhibit in the National Dredging Museum7. A manual operated drawer-like slide was moved between every passing bucket to catch the load. It seems very labour intensive and prone to accidents.

Even after breaking down these operational details in the design of the ‘Aristoteles’, the vessel serves its purpose in the story: it is a really useful dredge for dredge master Donald. Well done Daan.

Exhibit with vertical ladder at the national dredging museum
Exhibit with vertical ladder at the national dredging museum

Call to the audience

The exhibit is still there, but unfortunately, it is broken. The mechanism has to be repaired, any model building fanatics are invited to help the museum restore it. There is a special event for new volunteers, now!

References

  1. Freddy Milton, Wikipedia
  2. Daan Jippes, Wikipedia
  3. Oom Dagobert En De Ondergrondse Kluis, nr34, Disney
  4. Stripboekhandel Bul Super
  5. Read online Walt Disney’s Comics Penny Pincher comic – Issue #4, ZipComic
  6. Carl Barks, Wikipedia
  7. Nationaal Baggermuesum

See also

Graduation Omar Karam: Rock Cutting The Egyptian Way

Graduation presentation of Omar Karam
Graduation presentation of Omar Karam

Egypt is a great nation when it comes to ancient engineering. No other country has such a concentration of impressive monuments and such an interesting history as over there. If you are not convinced that modern Egyptians are not capable of great engineering feats you are wrong. Last Monday, Omar Karam graduated at our R&D department of Damen Dredging Equipment1 on his thesis about ‘CSD Rock Cutting.’

Cutting processes have been extensively described by Sape Miedema in ‘The Delft Sand, Clay & Rock Cutting Model’2. Omar has been using the frame work of Miedema to make some useful tools for the estimation of the production of our dredging equipment in rock. In due time, you will find the results of his thesis in the online dredge selection tool ‘Sandy’. Omar’s curiosity and ingenuity does not end here. He will continue studying at a university, but I do hope to meet him again, as he would be a valuable asset for our dredging community. Keep an eye out for him.

Program structure diagram of cutting force calculations
Program structure diagram of cutting force calculations

His graduation brings me back to my first lessons in dredging technology at the Delft University of Technology by the illustrious professor de Koning. In a sense he was an old school engineer, who hammered it in to us that thinking is done by doing it with your hands3. Back than the Polytechnic School was just rebranded to University and he was mocking that as a university, we had to set the topics in a broader perspective. So, he started his introduction on cutting technology with some slides of the unfinished obelisk at Aswan4 as every aspect of the cutting process could be illustrated.

Phases of chip forming in rock cutting
Phases of chip forming in rock cutting

The story according to de Koning is: ‘Around the quarry of the obelisk, they have found diorites5. These are some sort of volcanic balls of rock. In combination with the marks and scratches all around the obelisk, archaeologists believe these stones have been used to pound the granite. The impact compresses the bedrock and the resulting stresses fracture the contact surface(1). For every hit a whiff of dust is created. Eventually the dust is collected and scooped away for the next layer. Next, trees would be planted in the trench on one side of the obelisk. The growing root system displaces volume and create shear stress underneath the obelisk that would sever the obelisk from the bed rock(2). At last the trees are removed and dry wooden dowels would have been inserted in the shear cracks. Saturating the wooden dowels will make them grow. The last strands of rock will now be broken due to tensile stresses(3). Repeated insertion of new dry dowels and saturating them will lift the whole obelisk enough to pull some ropes under and carry the obelisk away to the building site.’

Although the diorites and the scratch marks are a smoking gun, current archaeologists argue about the feasibility of this process as experiments yield a very low production and it is doubted that the obelisk could be finished in the lifetime of the client6. Even if disputed, de Koning told a story that conveys the message; I vividly remember it and makes me understand the rock cutting process.

These mysterious monolithic ornamental spires have been an inspiration for many legends and stories. When we have solved the riddle of the rock cutting with diorite balls, it may inspire the development of new rock cutting technology for the dredging community and we can put the story of the obelisks to an end.7

End of the story on the cutting of obelisks (Credit: Uderzo)
End of the story on the cutting of obelisks (Credit: Uderzo)

References

  1. Innovation, Damen
  2. The Delft Sand, Clay & Rock Cutting Model, TU Delft
  3. De Koning (1978), Denken met de handen’, TU Delft
  4. Unfinished obelisk, Wikipedia
  5. Diorite, Wikipedia
  6. The Unfinished Obelisk, NOVA
  7. Asterix and Cleopatra, Goscinny-Uderzo

See also

Sniffing Out The Details Of Dredge System Fittings

Sniffer valve on the discharge line
Sniffer valve on the discharge line

The mixture carrying system of a cutter suction dredge, is more than just a cutter and a pump in a pontoon. In the dredge system, there are many valves and fittings, that make the system work. One question I was asked, what these extra valves do. Actually, there are several valves, that are worth mentioning. The sniffer valve, the vacuum relief valve and the non-return valve. For working in the designed operating point, you don’t need them. But, to get there and back, they can be quite useful.

Dredge system layout and fitting locations
Dredge system layout and fitting locations

The first valve is affectionally called a sniffer valve. A more descriptive name would be ‘discharge line de aerator valve’. Usually, it consists of a floating ball in a cage with a seat at the top, that can be closed by the ball. Provided the ladder is already under water and starting up the dredge pump from a fresh situation, probably air is in the high onboard discharge pipe sections on deck. Behind the dredge, the line goes down again and the air is basically trapped, preventing the dredge pump from properly priming. The sniffer valve allows the air to escape and the water to enter the floating discharge pipe at the water line. Problem solved.

Arrangement and operation of a sniffer valve
Arrangement and operation of a sniffer valve

On the other hand, when the discharge pressure falls, the ball floats down with the receding water level. This opens the top and allows air to enter the pipe again. Which is no problem as it can be expelled again through the same sniffer valve. When the water can flow away from the high section on board, this will break the water volume in the system. When opening the pump, only the small section between pump outlet and bulk head passage will fall in the pump well. Or, if properly executed: need to be drained and discharged.

A last function of the sniffer valve is in case there is a blockage of the suction pipe. There will be no new mixture flowing in, but the mixture in the discharge line still has a lot of momentum. For a 1 km, 500ø mm pipe, the mixture has the equivalent momentum of a 75 ton truck barrelling down the pipe at 80 km/h. You don’t stop that in an instant either. The mixture keeps flowing and draws a vacuum. The sniffer ball drops and allows air to enter the pipe.

A better way to prevent the vacuum, is to install a vacuum valve in the suction line. That will allow water in and enable you to clean the discharge line without a cavitating pump. Once the suction block is removed, the relief valve opens again and mixture can be inserted in the dredge line system.

Suction pipe vacuum relief valve
Suction pipe vacuum relief valve

In case there is a high discharge height, the mixture mass will not be broken by the sniffer valve. The geodetic pressure will close the sniffer and all of the mixture volume wants to return through the system out of the suction mouth; or open pump, swamping the dredge. To prevent this from happening, a non-return valve can be mounted in the onboard discharge line.

On board discharge non-return valve
On board discharge non-return valve

These fittings will cover most operational situations. There might be even more for exceptional situations, depending on the design choices by the manufacturer1 and to the taste of the owner.2 e.g. We provide a suction deaerating valve. Any ideas about such a provision?

Suction deaerating valve
Suction deaerating valve

References

  1. Cutter Suction Dredger, Damen
  2. Product Finder Dredging, Damen

See also

Sunken Treasures From ¡VAMOS! At Silvermines

Comment

04/03/2020, Mark:

I did receive the right comment about to the purpose of the suction deaerator valve. It is indeed for letting out the air trapped in the suction pipe when the ladder is being lowered. It could be argued that the air will also leave through the sniffer valve at the back of the dredge. If somehow, the air would have trouble escaping all the way to the back, the pump will be very slow in priming itself. Providing a deaerator on the local high at the bulkhead passage, the suction line can purge the air there and the pump starts quicker.