Ch. 6 Flashcards
What are the components of a towline system?
Working lines, fastening/release mechanism, best practices
What types of synthetic lines are used in shipwork?
Nylon, polyethylene, polypropolene blends, HMPE, and aramid fibers.
Are 100% nylon lines used for shipwork?
No, too elastic. However short sections of nylon lines may be used in composite lines
What are dacron line used for primarily?
Slings, mooring, and working lines
What are polypropylene and polyethylene lines used for?
Light work where a floating line is best
What are blended lines used for?
In all applications because they are stronger than polypro and polyethylene but lighter than dacron and they also float.
What are the two common trade names for HMPE fibers?
Spectra and dyneema
What purpose do wire rope pendants serve?
They protect the working lines from chafe where they pass through the chocks usually between 15 and 20 ft. in length.
What are the 5 common rope construction patterns?
3,6,8,12 strands and double braid
What types of wire ropes are suitable for pendants and working lines?
6x19 or 6x37 construction made from improved plow steel or extra improved plow steel
What are the purposes of a composition line?
Abrasion resistance, disposable component, accomodation of dynamic loading, creation of a weak link, flexibility and softness on working ends.
What are the 4 important characteristics of a winch?
Braking capacity, maximum line pull capacity, slick line speed, remote release.
What are the two main operational best practices?
Choose the right rope for the right job and use rope properly
List the common items of auxiliary equipment.
Heaving lines, tag lines, gob lines, and quick release straps.
Describe the heaving lines commonly used on tugs.
They are usually about 15 fathoms in length an inch to 1/2 inch in diameter to provide handhold to the deck force on the assisted vessel. A monkeys fist is on the other end for throwing.
