Hovercraft

-


Hovercraft:

 Hovercraft, also known as an air-cushion vehicle or ACV, is a craft capable of travelling over land, water, mud, ice, and other surfaces. Hovercraft are hybrid vessels operated by a pilot as an aircraft rather than a captain as a marine vessel.


Working of Hovercraft:

The basic mechanism of a hovercraft is very simple: there's an engine  that powers both a large central fan, pointing downward, and one or more other fans pointing backward. The central fan creates the lift that holds the craft above the waves; the other fans propel the craft backward, forward, or to the side. A rubber skirt (with or without fingers) traps a cushion of air under the craft. Side-wall hovercraft have only partial skirts: with solid sides and a skirt only at the front and back, they can be powered by quieter propellers on water jet  engines, making them quieter.
. The skirt greatly improved this situation with obstacles no longer being a problem.
A hovercraft can carry a payload exceeding 50 tons (45,000 kg), along with 30 personnel.






Elastomers are used in two key areas of hovercraft:


 A NR/Nylon fabric forms a skirt, which hangs from the sides in the form of conical flaps to guide the downward airflow. In addition, a polychloroprene /Nylon fabric forms an inflated tube along the periphery. This serves to cushion the craft and as an auxiliary flotation device

The primary military use of hovercraft is for ship to sea transport, shuttling troops and equipment, and for traversing beaches. They are especially effective for mine sweeping in shallow waters and have also been used for humanitarian relief. 

Comments

Post a Comment

Popular posts from this blog

Types of Bridge Bearing

-
Image
Types of bridge bearing  1. Elastomeric Bearing a.Plain elastomer pads b.Laminated Elastomeric bearings 2.Sliding bearing Mechanism a. PTFE  sliding material b.Alternative sliding material 3.High load multi Rotational building: a.Pot bearing b.Disc bearing c.Spherical bearings 4. Fabricated steel mechanical bearing a.Rocker bearing b.Rocker cum rolling bearing Elastomeric Bearing: It consists of elastomer manufactured from synthetic or natural rubber and can take both translation and rotation movements through elastomer deformation. The ability of elastomer to carry large vertical loads is because of reinforcement provision that prevents lateral bulging of elastomer. There are number of elastomeric bearing pads classified based on types of reinforcements used. For example, steel reinforced, plain, fiberglass reinforced and cotton duck reinforced elastomeric bearing pads Strength and response of each type is different, steel reinf...
Read more

Calendering

-
Image
Introduction: Calendering is the process of making thin sheet of rubber and also lamination of such sheet on to other substrate like fabric,cord warp sheet by passing through set if rollers under controlled Conditions. A calendar comprises of a number of rows or bowls held in frame. Rolls rotate in opposite directions either with even speed or with a friction ratio. Types Of Rubber material used Elastomers that can be used include: ·          Neoprene ·          SBR ·          Natural ·          Hypalon ·          Urethane ·          EPDM          Viton           Fluroelastomer         Butyl          Nitrile ...
Read more

Chloroprene rubber

-
Image
Introdu ction: It is the first synthetic rubber developed commerically.In terms of consumption polychloroprene has become a most important speciality rubber for non tyre application Special properties: excellent flame resistance Properties: Good ozone resistance Good flame resistance History if CR The polychloroprene story started in 1925 with the synthesis of the monomer. 1938-  DuPont began marketing the polymer as neoprene. 1940-  Development of copolymer with sulfur made 1950-  Soluble sulfur free mercaptan modified grades were introduced. 1960- pre cross-linked grades were developed 1970- improved. Pre cross-linked grades were developed. 1980- xanthogen disulfide grades were developed 1990- Newly developed M and XD grades combining low Temperature flexibility, heat resistance and dynamic properties as well as low fouling. T he major Manufacturers of Chloroprene rubber are 1.  Denka 2.  Neoprene 3.  B...
Read more