Caulking is one of several different processes to seal

Seal (mechanical)

A mechanical seal is a device which helps join systems or mechanisms together by preventing leakage , containing pressure, or excluding contamination...

 joints or seams in various structures and certain types of piping. The oldest form of caulking is used to make the seams in wood

Wood

Wood is a hard, fibrous tissue found in many trees. It has been used for hundreds of thousands of years for both fuel and as a construction material. It is an organic material, a natural composite of cellulose fibers embedded in a matrix of lignin which resists compression...

en boat

Boat

A boat is a watercraft of any size designed to float or plane, to provide passage across water. Usually this water will be inland or in protected coastal areas. However, boats such as the whaleboat were designed to be operated from a ship in an offshore environment. In naval terms, a boat is a...

s or ships watertight, by driving fibrous materials into the wedge-shaped seams between planks. A related process was formerly employed to join sections of cast iron

Cast iron

Cast iron is derived from pig iron, and while it usually refers to gray iron, it also identifies a large group of ferrous alloys which solidify with a eutectic. The color of a fractured surface can be used to identify an alloy. White cast iron is named after its white surface when fractured, due...

 sewerage

Sanitary sewer

A sanitary sewer is a separate underground carriage system specifically for transporting sewage from houses and commercial buildings to treatment or disposal. Sanitary sewers serving industrial areas also carry industrial wastewater...

 pipe

Water pipe

Water pipes are pipes or tubes, frequently made of polyvinyl chloride , ductile iron, steel, cast iron, polypropylene, polyethylene, or copper, that carry pressurized and treated fresh water to buildings , as well as inside the building.-History:For many centuries, lead was the favoured material...

.

Caulking is also the term to describe the process used to make rivet

Rivet

A rivet is a permanent mechanical fastener. Before being installed a rivet consists of a smooth cylindrical shaft with a head on one end. The end opposite the head is called the buck-tail. On installation the rivet is placed in a punched or pre-drilled hole, and the tail is upset, or bucked A rivet...

ed iron or steel ships and boilers watertight or steamtight.

The same term also refers to the application of flexible sealing compounds to close up gaps in buildings and other structures against water

Water

Water is a chemical substance with the chemical formula H2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at ambient conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state . Water also exists in a...

, air, dust

Dust

Dust consists of particles in the atmosphere that arise from various sources such as soil dust lifted up by wind , volcanic eruptions, and pollution...

, insect

Insect

Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...

s, or as a component in firestop

Firestop

A firestop is a passive fire protection system of various components used to seal openings and joints in fire-resistance rated wall and/or floor assemblies, based on fire testing and certification listings....

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