SECTION C.-PATENT APPLIANCES FOR LAUNCHING SHIPS' BOATS

The Welin Patent Davits. It seems almost superfluous to describe in great detail the various apparatus which the Welin Davit & Engineering Co., Ltd., have evolved for the purpose of providing the most expeditious and satisfactory means for launching ships' boats, because they are so well known and understood by shipowners and shipbuilders throughout the continent of Europe and in America. There is no question appertaining to the life-saving equipment on ships which has not received this firm's careful and studied consideration.

Attention has already been given in Section A to the various systems which are in operation for dealing with the transportation and stowage of lifeboats, and patented by the Welin Davit Co.

The principal types of Welin davits comprise single-acting, double-acting, and overframe. There are, of course, numerous modifications of these three primary types, and to which only brief reference can now be made.

"S.A." The Single-acting Type is made in fifteen different sizes and is mainly intended for operating one lifeboat only. Figs. 243 and 244 show this particular davit installed on one of the largest ocean-going passenger steamers, and incidentally depict the crew at boat drill. The frame and davit arms are made of the best cast steel of a tensile strength not less than 60,000 and not more than 72,000 pounds per sq. in., with an elongation of 22 per cent. in two inches. The quadrant is geared to a path on the lower portion of the frame, and the travelling screw is made of "Tobin " or phosphor bronze, abutting on hardened steel thrust washers so as to reduce friction to a minimum. The design of the quadrant gives increased leverage and power when the stresses on the davit are at their maximum. In operating the screw the lifeboat is lifted from the stowage chocks without any previous adjustment and allows the keel and bilge of the boat to easily clear the deck of the vessel. The working of the mechanism to bring the boat from the stowing to the outboard position is simplicity itself, and would enable even an unskilled operator to handle the same with safety should the necessity arise.

"P" Type.-This is a simple modification of the single-acting type, obtained by somewhat shortening the frame, and introducing a longer arm. It is used in cases where an open Class I.

inboard.

cutboard.

Lifeboats stowed

Lifeboats swung

lifeboat is carried above a Class II. boat having collapsible bulwarks, or where one open Class I. boat is carried above another; in the latter case a special form of pedestal chock is used, otherwise the working of the gear is exactly the same as in the other types. Fig. 129 shows this particular type of davit fitted under the conditions described. The lower boat being a 28-ft. Lundin decked lifeboat.

Trifling modifications are introduced into all the various types when wire falls are used, but in no case do such modifications, where they exist, in any way alter the general working principle of the gear.

"D.A." Double-acting Type.-This design of davit is illustrated in Fig. 245. The purpose of this davit is to handle a double row of boats as the photograph indicates; it will be noticed that the quadrant at the heel of the arm is considerably extended beyond that of the single-acting davit.

"F" Type.(Single and double-acting.) This particular davit is utilised when a number of boats have to be transferred across the deck to a point within reach of the lowering davits, and can be used in conjunction with either the single or doubleacting davit.

"L" Type is a particularly strong davit used for handling steam and motor launches, hospital boats, etc.

"O" Type is an overframe davit, the shape of which is in the form of a goose-neck. The illustration given in Fig. 246 indicates the practical features of this design. The keel of the boat rests on a projection attached to the davit arms, and the boat neatly stows in chocks also secured to the arms. There are three positions in which the boat can be carried, viz., inboard, harbour position, and outboard, the chocks being so arranged as to prevent any possible movement of the boat at each of these positions.

This type of davit is well suited to accommodate the emergency boats, and quite a large number were fitted to Royal Fleet auxiliaries during the Great War, for the British Admiralty.

A distinct advantage is secured when this davit is fitted to a promenade deck, as an unobstructed view is obtained under the keel of the boats by the passengers.

"M" Type. This is a small single davit fitted to yachts for accommodating the dinghy.

"L.D." Type.-Space will not permit the use of many of the photographs which are still in the possession of the writer, illustrating the various devices of the "Welin" systems of dealing with the launching of ships' boats. This type is used on large

vessels, where it has been found undesirable to place the whole of the lifeboats on the upper deck. The arrangement gives a clear promenade deck and the boats being situated nearer to the water than if stowed on the boat deck, increased stability is given to the vessel.

The Norton Sheath Screw Davits. This particular davit was designed by Mr. Norton of the United States of America and is

now manufactured by the American Balsa Company, Inc. (Welin Marine Equipment Co.), Long Island City, New York.

The design is very simple and the combination is almost entirely built up from structural steel and is therefore comparatively light. The davit arm is an H bar having a forged head securely riveted thereto, with good solid hinges at the heel. The frame, or deck stand, is constructed of bracket plates and angle bars.