MANUFACTURER'S STANDARD SPECIFICATIONS.

Revised to February 6, 1903.

STRUCTURAL STEEL.

1. Process of Manufacture. Steel may be made by either the Open Hearth or Bessemer Process.

2. Testing and Inspection. All tests and inspections shall be made at the place of manufacture prior to shipment.

3. Test Pieces. The tensile strength, limit of elasticity and ductility shall be determined from a standard test piece cut from the finished material. The standard shape of the test piece for sheared plates shall be as shown by the following sketch: See Fig. 8.

On tests cut from other material the test piece may be either the same as for sheared plates, or it may be planed or turned parallel throughout its entire length, and in all cases where possible two opposite sides of the test piece shall be the rolled surfaces. The elongation shall be measured on an original length of 8 inches, except as modified in section 12, paragraph c. Rivet rounds and small bars shall be tested

of full size as rolled.

Two test pieces shall be taken from each melt or blow of finished material, one for tension and one for bending; but in case either test develops flaws, or the tensile test piece breaks outside of the middle third of its gauged length, it may be discarded and another test piece substituted therefor.

4. Annealed Test Pieces. Material which is to be used without annealing or further treatment shall be tested in the condition in which it comes from the rolls. When material is to be annealed or otherwise treated before use, the specimen representing such material shall be similarly treated before testing.

5. Marking. Every finished piece of steel shall be stamped with the blow or melt number, and steel for pins shall have the blow or melt number stamped on the ends. Rivet and lacing steel, and small pieces for pin plates and stiffeners, may be shipped in bundles securely wired together, with the blow or melt number on a metal tag attached.

6. Finish. Finished bars shall be free from injurious seams, flaws or cracks, and have a workmanlike finish.

7. Chemical Properties. Steel for buildings, train sheds, highway bridges and similar structures shall not contain more than 0.10% of phosphorus. Steel for railway bridges shall not contain more than 0.08% of phosphorus.

8. Physical Properties. Structural Steel shall be of three grades, RIVET, RAILWAY and MEDIUM.

9. Rivet Steel. Ultimate strength, 48,000 to 58,000 pounds per sq. inch. Elastic limit, not less than one-half the ultimate strength.

Percentage of elongation,

1,400.000

Ultimate strength.

Bending test, 180 degrees flat on itself, without fracture on outside of bent portion.

IO. Steel for Railway Bridges. Ultimate strength, 55,000 to 65,000 pounds per sq. inch. Elastic limit, not less than one-half the ultimate strength.

Percentage of elongation,

1,400.000

Ultimate strength.

Bending test, 180 degrees to a diameter equal to thickness of piece tested, without fracture on outside of bent portion. II. Medium Steel. Ultimate strength, 60,000 to 70,000 pounds per sq. inch. Elastic limit not less than one-half the ultimate strength.

Percentage of elongation,

1,400.000

Ultimate strength.

Bending test, 180 degrees to a diameter equal to thickness of piece tested, without fracture on outside of bent portion.

12.

Modifications in Elongation for Thin and Thick Material. For material less than 5/16 inch, and more than 34 inch in thickness, the following modifications shall be made. in the requirements for elongation:

a. For each increase of inch in thickness above 3/4 inch, a deduction of 1% shall be made from specified elongation, except that the minimum elongation shall be 20% for eye-bar material and 18% for other structural material.

b. For each decrease of 1/16 inch in thickness below 5/16 inch, a deduction of 21⁄2 per cent. shall be made from the specified elongation.

C. In rounds of 5/8 inch or less in diameter, the elongation shall be measured in a length equal to eight times the diameter of section tested.

d. For pins made from any of the before-mentioned grades of steel, the required elongation shall be 5 per cent. less than that specified for each grade, as determined on a test piece, the center of which shall be one inch from the surface of the bar.

13. Variation in Weight. The variation in cross-section or weight of more than 22 per cent. from that specified will be sufficient cause for rejection, except in the case of sheared plates which will be covered by the following permissible variations:

a. Plates 121⁄2 pounds per sq. foot or heavier, up to 100 inches wide, when ordered to weight, shall not average more than 21⁄2 per cent. variation above or 21⁄2 per cent. below the theoretical weight. When 100 inches wide and over, 5% above or 5% below the theoretical weight.

b. Plates under 121⁄2 pounds per sq. foot when ordered to weight, shall not average a greater variation than the following: Up to 75 inches wide, 22 per cent. above or 21⁄2 per cent. below the theoretical weight; 75 inches wide up to 100 inches wide 5% above or 3% below the theoretical weight. When 100 inches wide and over, 10 per cent. above or 3 per cent. below the theoretical weight.

C.

For all plates ordered to gauge, there will be permitted an average excess of weight over that corresponding to the dimensions on the order, equal in amount to that specified in the following table:

Table of Allowances for Overweight for Rectangular Plates When Ordered to Gauge.

Plates will be considered up to gauge if measuring not over 1/100 inch less than the ordered gauge. The weight of I cubic inch of rolled steel is assumed to be 0.2833 pound.

STRUCTURAL CAST IRON.

Except when chilled iron is specified, all castings shall be tough gray iron, free from injurious cold-shuts or blow holes, true to pattern and of a workmanlike finish. Sample pieces, one inch square, cast from the same heat of metal in sand moulds, shall be capable of sustaining on a clear span of 4 feet 8 inches, a central load of 500 pounds when tested in the rough bar.

Still another set of specifications is here given. This set is more suitable for building construction and represents the main points taken from several specifications used on actual work and forming part of the iron man's contract. The arrangement of the various sections follows closely the outline given in the beginning of this chapter.

SPECIFICATIONS FOR MANUFACTURING, FABRICATING, INSPECTION AND ERECTION

OF STRUCTURAL STEEL

for the Loft Building at the S. W. Corner 18th St. and 4th Ave., N. Y. City.

H. Smart, Architect.

John Doe, Owner.

GENERAL.

V. R. Wise, Engineer.

Site Examination. The iron contractor is to see the site, and to estimate for everything necessary to complete his work on the building, as shown on plans as herein specified.

Drawings and Specifications. Any iron work shown on the plans and not particularly called for in the specifications, or any iron work called for in the specifications, and not shown on the plans, must be put in the same as if it were

both shown and called for. In fact, these specifications and the accompanying drawings are intended to explain and complete each other and include everything necessary and requisite for the proper completion of the iron work in this building, notwithstanding that every item necessarily involved in the work is not particularly mentioned.

Extras and Omissions. No omissions and no additional work shall be undertaken, except upon written order signed by the architect and approved by the owner. The cost of such omission or additional work must be agreed upon before commencing same.

Work Contrary to Plans and Specifications. Any work not in accord with these specifications and the accompanying plans must be taken out and replaced at the contractor's expense by work complying in all details with these plans and specifications.

Shop Drawings. The contractor shall submit to the architect or engineer for approval, all shop drawings and details. The approval of these, however, is only as to strength and does not relieve the contractor from responsibility for his dimensions.

DIMENSIONS. The contractor must verify all figures on drawings before laying out the work; figured dimensions. are to be used in preference to scale measurements; scale drawings and details in preference to small scale plans. The contractor will be held responsible for the correctness of all dimensions at the building.

Errors. Any error or omission and any discrepancy of any kind should be referred to the architect for correction as soon as discovered.

Sizes. The work covered by the contract is completely shown on the accompanying plans and these specifications; all sizes and weights of beams girders and columns are marked on the plans and the column schedule.

Changes. The contractor may, if he so desires, simplify the sizes of column sections by increasing their weight. He may replace standard beams by special beams of greater strength and weight when this will save time in delivery. He may also change splicing points indicated on the column schedule. Any of these changes, however, must not be made without the written approval of the engineer.

Official Requirements. The contractor shall comply with all State and Municipal Laws and Ordinances relating to building construction. The contractor must conform to the