Glossary of Marine Terms
H
harbor boat
any powered vessel which is used primarily in harbor operations.
hardenability
this relates to the ability of steel to harden deeply upon quenching and takes into consideration the size of the part, the method of quenching and the analysis and grain size of the steel. carbon steels are considered as shallow hardening and various alloy and tool steel grades are considered deep hardening or through hardening.
hardening
increasing the hardness by suitable heat treatment, usually involving heating and cooling. when applicable, the following more specific terms should be used: age hardening, case hardening, flame hardening, induction hardening, precipitation hardening, and quench hardening.
hardness
the ability of a metal to resist penetration. the principal methods of hardness determination are the brinell, rockwell and scleroscope tests.
hatch
a removable cover over the cargo hold of a vessel.
hawser
a large circumference rope used for towing or mooring a vessel or for securing it at a dock.
head of navigation
the uppermost limit of navigation from the mouth of a waterway.
heat treatment
an operation or combination of operations involving the heating and cooling of a metal in the solid state for the purpose of obtaining certain desirable conditions or properties. heat treating operations would be annealing, normalizing, quenching and tempering, etc.
hip towing (hipping)
a method of towing whereby the vessel being towed is secured along-side the towboat.
home port
the port city which is the home base of a vessel or the city from which it is documented.
horsepower
a standard unit of power which is often classified in connection with engines as brake, continuous input, intermittent, output, or shaft horsepower.
hull
the main body of a vessel which provides flotation.
