Caulked Joint

Caulked Joint is water-tight, and occurs in piping, wrought and cast ironwork, etc, and is made by stuffing the cavity in the socket, or between plates, castings, etc, with oakum, brown paper, and white or red lead, india-rubber, wood wedges or slips, iron or rust cement, or gaskets of spun yarn, either white or tarred. One or other of these materials is vigorously driven into the cavity or crevice with a hammer and thick steel chisel, of different shapes and sizes, called a caulking iron or tool, excepting, however, the wood and india-rubber, which do not require the exercise of much force. The joints of box girders are sometimes caulked to render them air-tight, to preserve the interior from corrosion; and in other riveted work, fished joints are not unfrequently caulked by punching down with a caulking tool the butts or edges of the plates drawn apart by the process of riveting until they are brought close. In a similar way, the heads or points of rivets and the junctions of plates in water-tight work are caulked down if not left sufiiciently close. When the pitch is very wide, the plates will spring under the operation without great care. This kind of joint is otherwise written calked or cauked. There is another variety, however, which, though identically named, is essentially different in purpose and principle. It is formed when a caulking enters into the composition of the joint. This term caulking, calking, cauking, or corking, is given to an iron fang or projection, or flattened end turned up or down, or both (common in | chimney and tie-bars), for building into masonry, as well as to a tenon or projecting stub cast on columns, pilasters, standards, girders, etc, for letting into bearing or bed plates, bedstones or blocks. Hence the resulting joint is obviously either calked, caulked, cauked, or corked.

Caulked Joint 77

Fig. 76.

Cement Joint

Red and white lead in equal parts mixed with linseed oil forms a good cement for hot-water pipes. Under Rust Joint will be found described another variety. Eaves gutters, etc, are jointed to remain watertight, as noticed under Bolted Joint.

Chain Riveted Joint

A double, or triple, etc, riveted joint formed either by lapping the main plates, or by means of cover or fish plates, the characteristic of the joint consist-ing in the rivets being similarly and equally distributed, and standing regularly behind each other, along equidistant lines parallel to the direction of the stress. Fig. 77 shows a triple chain riveted lap joint, in which, however, one of the cross lines is erroneously drawn full instead of dotted.

Chain Riveted Joint 78

Fig. 77.

Chamfered Joint consists in chamfering off the arris of bed plates, etc, to present to the superincumbent pressure as obtuse an edge as possible around the bed without appreciably diminishing its bearing surface.