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All weld specimens shall be prepared and the bend tests shall be conducted in the presence of an inspector.

After the specimens have been bent in the jig in accordance with the regula-. tions in this part the inspector shall examine the weld. A crack in the weld metal or between the weld and the base metal which, during or at the completion of the test in the bending jig, opens up more than one-eighth inch in any direction shall be cause for rejection.

(h) The passing of these qualification tests with direct current equipment shall qualify welders with direct current equipment only. The passing of these qualification tests with alternating current equipment shall qualify welders for welding with alternating current equipment only. If both types of equipment are to be used by a welder, he shall be qualified with both alternating current and direct current equipment.

(i) In case it is desired to use material the physical properties of which are not known, it will be necessary that physical tests be made to determine the tensile strength of the material and its ductility before the weld specimens are prepared.

(j) Welding operators who have been primarily tested and certificated shall be assigned an identifying number, letter, or symbol, which shall be stamped on the pipe adjacent to the welds which they make, whether the process used is hand or machine.

(k) The inspector shall require any welding operator to repeat these tests when in his opinion the work indicates a reasonable doubt of the welding operator's ability. In such cases the welding operator shall not be permitted to resume work until he passes the retest.

(1) Any certificated welding operator who has not been employed as a fusion welder for a period of 3 months or more shall be required to pass the requalification tests even though he has previously passed such tests.

(m) The requalification test specimens shall be identical with the primary test specimen with the same equipment or equipment equivalent thereto in performance and condition as used in primary tests. It shall be conducted under the supervision of a duly authorized

inspector who shall report results of test to the Director. Such test shall meet the requirements of the rules in this section.

(n) Design of piping: The piping shall be designed to avoid excessive strains due to expansion and the working of the ship.

(o) Layout and dimensions of piping: Prints showing the layout and dimensions of the piping shall be forwarded to the Director for approval. Sections of the pipe shall be welded in the shop as far as practicable. All welded joints made on shipboard shall be in positions where there is sufficient space to allow proper access for the welding, and such welds shall be definitely indicated on the plans by the use of appropriate American Welding Society weld symbols or details of the welds. A sufficient number of detachable joints shall be used in installing the piping to facilitate removals. Valves and other fittings may have either flanged or welded connections to the pipes but flanged joints shall be used where necessary to facilitate overhauling of machinery or the valves themselves.

(p) Types of welded joints to be used: Butt joints shall be used for pipes over 2 inches nominal pipe size and shall be either double-welded or welded with a backing-up strip on the inside of the pipe. Pipes not over 2 inches nominal pipe size may be connected by ferrules fitted over the ends of the pipe and attached by circumferential fillet welds to the pipe, or by using bell-and-spigot joints and uniting the end of the bell to the outside of the pipe by a circumferential fillet weld.

(q) Stress relieving: (1) All welded joints over 21⁄2 inches nominal pipe size except fire lines and oil lines at normal temperature, shall be stress-relieved.

(2) The welds of plain carbon-steel pipe and adjacent piping for a length of six times the wall thickness of the pipe shall be heated uniformly to at least 1,150° F. and up to 1,250° F. The weld and adjacent piping shall be brought slowly up to within the specified temperature range and held at that temperature for a period of time proportioned on the basis of at least 1 hour per inch

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Cleaning of Passes

Indicate temperature of

*Give degree of preheat, if any. weld metal just prior to the deposition of each succeeding pass.

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next to the valve to a uniform temperature for a length of six times the wall thickness without overheating the valve. In such a case the heated zone shall extend to at least 2 inches on the valve side from the line of fusion of the joint and the temperature shall be allowed to diminish gradually toward the valve.

(4) All complicated connections, such as manifolds, shall be stress-relieved as a whole in a furnace provided for the purpose before being taken on shipboard.

(5) The piping shall be so designed that it will be free to expand in a longitudinal direction when the joints are stress-relieved, thus eliminating stresses that might result through contraction of the piping after the stress-relieving.

(r) Radiographic and other tests: All welded joints on piping exceeding 22 inches in diameter shall be tested either by radiography or by using a paramagnetic powder dusted over the area to make sure that there are no cracks or other defects. Should the quality of a joint be questioned by an inspector of the Bureau the weld shall be cut out and the joint rewelded.

(s) Hydrostatic tests: Hydrostatic tests shall be made on the piping at twice the maximum pressure to which the piping will be subjected in service.

(t) General requirements: Before any qualification tests of welding, operators are conducted, each manufacturer shall prepare for test the types of test specimens hereinafter specified for the purpose of qualifying his welding process.

(u) Manufacturer's record of process: A complete record of the manufacturer's process shall be made in the form shown in Fig. W-34 to establish the definite limits of all essential variables involved. The manufacturer shall conduct all welding in accordance with the requirements of his process record, after his process of welding has been approved.

(v) Number, type, and size of test welds: The test specimens shall be prepared in accordance with the requirements of this section. One test specimen

shall be prepared for each process and welding position which will be encountered.

(w) Base metal and its preparation: The base material and its preparation for welding shall comply with the manufacturer's process record. For all test welds, the dimensions of the base material shall be such as to provide sufficient material for the test speciments called for.

(x) Positions of test welds: The positions of pipe welding will be classified as follows: (1) horizontal-rolled, (2) horizontal-fixed, and (3) vertical-fixed. If a process is investigated for the horizontalfixed position, it need not be repeated for the horizontal-rolled position, provided that the same welding process is employed, as defined by the manufacturer's process record, Fig. W-34. For welds representing the horizontal-rolled and the horizontal-fixed positions, the axis of the pipe shall be approximately horizontal. For test welds representing the vertical-fixed position, the axis of the pipe shall be approximately vertical. The pipe shall be rotated for the test weld representing the horizontal-rolled position, and shall not be rotated for test welds representing the horizontal-fixed and vertical-fixed positions.

(y) Test specimens: Number, type, and preparation: The test specimens shall be prepared and tested in accordance with the applicable provisions of paragraphs (e), (f), and (g) of this section. (R.S. 4405, 4417a, 4418, 4429, 4433, as amended; 46 U.S.C. 375, 391a, 392, 407, 411) [As amended by Order 84, Mar. 10, 1941; 6 F.R. 1406]

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Subchapter G-Ocean and Coastwise: General Rules and Regulations

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(g) No type or make of mechanical or gravity davit shall be used unless it has first been approved by the Board.

(h) No mechanical davits of a character which require manual or other power to turn the boats out to the position for lowering into the water shall be fitted on any vessel the keel of which is laid after September 1, 1941, if such davits are to handle a lifeboat which, without its complement of persons on board, but having on board all air tanks and other lifeboat equipment, exceeds 5,000 pounds total weight: 1. e. 2,500 pounds for a single davit arm. An exemption to this requirement may be granted during the period of the national emergency, proclaimed by the President on May 27, 1941, if evidence is presented to the Bureau to substantiate a claim that compliance with this requirement would materially delay the completion and delivery of the vessel.

CROSS REFERENCE: For proclamation of May 27, 1941, see Proc. 2487, page 78 of this Supplement.

(i) Davits of an approved type, which are capable of swinging the boats into the lowering position without the application of any effort or external force other than that necessary to operate the releasing mechanism, allowing the boat to move from the stowed position to the lowering position by the force of gravity, shall be provided to handle all lifeboats the total weight of which, including air tanks and lifeboat equipment, but without the complement of persons on board, exceeds 5,000 pounds.

(j) Where steel castings are used for davit frames or davit arms this material shall be fully annealed and comply with the following requirements:

(In substantial agreement with A. S. T. M. Spec. A-27-39 and A-215-39T)

Tensile strength minimum psi 66,000 Yield point minimum psi 33,000

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60,000 to 72,000 0.5 T. S. 1,500,000 Ten. Str. 22

Elongation in 8 in. min. per cent_
Elongation in 2 inches min. per cent__

(n) Where welding is employed in the construction of davits, the welders shall be qualified by the Bureau.

(0) All moving parts of davits shall be provided with bushings of nonferrous metal, roller or ball bearings properly lubricated.

(p) An inspector shall be present at the foundry where castings are made to witness the tensile and bend tests prescribed. The manufacturer shall furnish an affidavit stating that the required tests for annealing have been made. When the inspector has satisfied himself that such castings comply with the requirements, he shall stamp the davit arm and frame with the letters, B. Μ. Ι. Ν., the initials of his name and the letters, F. T., and date of inspection.

(q) Each davit and frame shall be tested for strength and operation at the place of manufacture in the presence of an inspector.

(r) All mechanical and gravity davit arms or frames shall be tested at the extreme outboard position by suspending from the eye or end of each davit arm a weight equal to the weight of the fully loaded and equipped boat (including full complement of persons at 165 pounds each) for which the davit is to be approved, plus 10 percent. Under this test, a davit arm or frame shall show no permanent set or undue deflection. While this test is being conducted, the frame and arms, if of cast material, shall be subjected to a test by being hammered to satisfy the inspector that the castings are sound and without flaw.

(s) While this test load is suspended, the operating gear of mechanical davits shall be tested by being operated from inboard to the extreme outboard position with the same operating crank or device used in actual practice aboard ship.

(t) The manufacturer shall affix to the davit arm and frame a heavy plate giving the name of manufacturer, date of inspection, serial number, capacity load, space for the inspector's initials, and the letters B. M. I. N. After the inspector has satisfied himself that the assembled installation meets the requirements, he shall stamp the manufacturer's plates with his initials. Each set of davits shall be marked with identical serial numbers by the manufacturer.

(u) No davit arm or frame comprising mechanical or gravity davits shall be placed on board any vessel until all of the requirements of the rules of this section have been fully complied with. Whenever mechanical or gravity davits or parts of davits, such as davit arms, or frames, are installed on vessels, to take the place of davits, davit arms, or frames which have become damaged or broken, such davits or frames shall have the manufacturer's name plate affixed thereto. (R.S. 4405, 4488, 4491, as amended; 46 U.S.C. 375,481,489) [As added by Order 138, Aug. 18, 1941; 6 F.R. 4265]

NOTE: $ 59.3 was amended by amending paragraphs (g) to (k), and by adding paragraphs (1) to (u) by Order 138, Aug. 18, 1941; 6 F.R. 4265.

§59.3a Mechanical means for lowering. (a) On all passenger vessels where the height of a boat deck exceeds 20 feet from the lightest seagoing draft, wire falls and mechanical means for lowering shall be provided for each set of davits.

(b) Winches, proposed for use in new installations, shall be of approved type and those which are contracted for on or after January 1, 1942 shall, in addition to conforming to the following requirements, be subjected to the shop test with a 100 percent overload and opened up for examination prior to Board approval.

(c) Plans and detail specifications of all lifeboat winches shall be submitted by the manufacturer to the Board for type approval. The plans shall show dimensions of all parts and complete bill of material used in the construction of the winches.

(d) Inspection openings shall be provided in the winch housing or the housing shall be so arranged to permit examination. Screws, bolts, nuts, pins, etc., used in the internal and brake assemblies, shall be fitted with lock washers, cotter pins, or suitable backing stops.

(e) Worm gears, spur gears, or a combination of both may be used in the construction of the lifeboat winches. All gears shall be machine cut and constructed of steel, bronze, or other suitable materials. The use of cast iron for gears is not permitted. Gears shall be press-fitted on the shaft, and keys shall be properly fitted and secured.

(f) Motor clutches, when used, shall be of either frictional or positive engaging type. When one motor is used for two winches, the clutch shall be so arranged that only one winch shall be engaged at any one time. The clutch operating level shall be capable of remaining in any position when subject to vibration, and shall be so arranged that when in neutral position both lifeboats may be lowered simultaneously.

(g) Winch drums for gravity davits shall be designed with grooves so that not more than one layer of the falls winds on the drum. Drums shall be so arranged as to keep the falls separated.

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