JETCRAFT. Водомёт. Водомётный движитель. Теория. Лодка. На что обратить внимание. Руководство пользователя. (Boats: What to Look For . Buyer guide) |
Лодка. На что обратить внимание. |
Marathon Marine - web. Cтатья очень доходчиво рассказывает НА ЧТО ОБРАТИТЬ ВНИМАНИЕ при покупке лодки или водомётного катера.
NEW. Росомаха (img) русский конкурент Harbercraf / Jetcraft
Byuer Guide Руководство покупателя
Фотографии с выставки "MIBS 2009" Закон и катер. Постановка на учёт катера со стационарным двигателем. дюймы в сантиметры
Форумы на тему... с переводом.
Harbercraft 1875 J-Max White Water (img)
2075 White Water (img)
1875 J-Max XS (img)
2175 XS Фотографии с выставки "Охота и рыбалка - 2008"
Marathon Marine and Northwest Jet Boats (link)
PHANTOM Jet Boats (link)
RiverPro®. (link)
North Silver PRO 675Jet lnk
Росомаха (img)
Tom 525. Томь 525.
Коллекция ссылок на тему: водомёты для судов (Links). Курс доллара
Друзъя
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A Word about Welding
You are buying a welded boat. The quality depends on the welding. Welding depends upon proper heat selection, speed of weld, type of material being welded etc. A properly welded and reinforced boat will last for years – an improper one will develop cracks and other problems. Suck marks, caterpillar tracks Welding requires the (melting and fusion and mixing) of the two pieces being welded (плавление и слияние и перемешивание)) together with a (filler wire). Weld too hot and you burn through and distort the material. (заполняющая проволока) Weld too cold and you do not get fusion and melting of the two pieces – you just get melted filler wire sitting on top of the two pieces. Proper fusion in materials up to 1⁄4” thick shows up on the opposite side of the material as (distortion) lines and marks. These marks are generally call ‘suck marks’ or ‘caterpillar (искривления) tracks’. (Eliminating) these in the welding process requires minimizing heat and therefore (Устранить) fusion. It also minimizes the strength of the (joint). In other words, one way to make a (соединение) cosmetically more (appealing) boat is to ‘cold weld’ the boat. The cheapest, easiest and (привлекательный) weakest weld is a cold weld. Stay away from boats like this unless you are a light duty user, as they will not stand up. If you are looking at a weld on a side for example, on all the quality boats you will see the weld line running down the side. A certain amount of paint preparation and bodywork can reduce the line, but it generally does not disappear. If you do not see this line where
the welds are make sure you are getting a boat that has been properly welded.
If you do see a boat where you cannot see that line it means:
� The boat was cold welded
� Substantiation body work was done to hide the distortion
� The material is thick enough to hide the line
� There is no joint there.
On the flip side, welding weakens aluminum. When heating the aluminum strength is
taken out of material. The more heat that is used to weld the boat, the weaker the
aluminum becomes. This is one of the reasons that it is important to use higher grades of
material for structural components. The initial higher strength or thickness of the material
helps compensate for the reduction in strength after welding.
That is why Marathon uses .160 for stringers and .125 for sides, in order to compensate 4,064 мм 3,175 мм for the welding.
Folded, ‘Origami’ Construction
There are techniques that (rely) on folding the boat ‘origami’ style with minimal welding. (полагается) In order to fold the boats, softer and generally thinner alloys have to be used. These softer
and thinner alloys are much more susceptible to cracking out and failure than what
Marathon uses.
If you look at most brands of welded boats, you will find that this technique is rarely
used. (Besides the drawback) of using softer alloys, these boats rarely have (rub rails). These (Кроме того отрицательная сторона) (от трения ограда – привальный брус?) protect the sides and paint from abrasion and scratches when rubbing against things like
docks and other boats. Secondly they do not have the harder alloys protecting and
strengthening the gunwales.
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Boats: What to Look For. НА ЧТО ОБРАТИТЬ ВНИМАНИЕ при покупке лодки. Введение Сварные лодки в общем Наши предпочтения
Buying a Welded Boat for the First Time
Bottom Width and Engine Size and Type.
Stability at Speed: Porpoising versus bow down Дельфинирование.
Boat Materials: Aluminum versus Fiberglass .
Cost differences between glass and aluminum . Сравнение стоимости стекловолокна и алюминия. Types of Aluminum. Типы алюминия.
Material Thickness
A Word about Welding
Suck marks, caterpillar tracks
Folded, ‘Origami’ Construction
Deadrise (Vee)
Planing Hull Bottom Types Корпус с дном плоского типа
Constant deadrise V (including modified V hulls)
Flat bottom hulls (8 degrees deadrise or less)
Bow Entry Types. Тип носа катера
Radius Bottom Круглое дно.
Lateral Stability During Planing Turns
Bottom Shape and Jet Intake
Planing Ability
Reverse Chines
Bottom Width: Flair is not everything
No Trim.
Hull Construction Standards
Shallow Water Operation
No Exposed Drive
Safety
Thrust line and Center of Gravity In line
Propeller Torque is Different than Impeller Torque
Propulsion Resistance.
Power Plants Силовая установка. Derived from Impeller Curves.
RPM Curve Derivation
Conclusion
Hull Resistance. Boat attitude..
Jet Drives
How jets work .
Impeller
Cut.
Cut, Speed and Load
Wear ring.
Nozzle
Stator.
Hard Anodized.
Cavitation .
Intake
Seals
Mixed flow
Axial flow.
Outboard jet:
Inboard jets:
So, what is the best jet?
Corrosion.....
UHMW...
Jet Diagnosis...
Rattle at Idle (V8 boats)
Speed too low for a Given RPM.
Poor acceleration or ‘holeshot’, combined with high top end
Definitions.
Porpoising .
Chine walk: 9
Ram effect .
Static thrust:
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Водомётный движитель. ТЕОРИЯ.
Адрес для переписки:
Spiridonov S. E.
Лодка. На что обратить внимание. |
JETCRAFT. Водомёт. Водомётный движитель. Теория. Лодка. На что обратить внимание. Руководство пользователя. (Boats: What to Look For . Buyer guide) |