Department of State Growth
SECTION675-CAST STEEL BARRIER RAILING POSTS
675.01GENERAL
This section covers the manufacture of cast steel barrier railing posts, the properties of the cast steel and the testing procedures required.
Cast steel for railing posts and sleeves shall conform to the requirements of AS2074.
675.02MATERIALS SPECIFICATION
Cast steel with minimum yield stress of 245MPa shall conform to AS2074 GradeC41.
Cast steel with minimum yield stress of 340MPa shall conform to AS2074 GradeL1A.
Technical requirements for steel castings shall comply with AS4738.1.
675.03HEAT TREATMENT
All castings shall be heat treated in accordance with Clause2.3.2 of AS2074.
675.04SHAPE AND TOLERANCES
The castings shall be made to the shape and dimensions shown on the drawings and within the tolerances specified:
thickness of members+2 mm /0 mm
diameter of holes+2 mm /0 mm
overall dimensions+2 mm /0 mm
flatness of base2 mm maximum on convex surface
(measured along all edges and diagonals of base plan area).
The web centreline shall not be out of square with the plane of the base by more than 1mm per 100mm height of the web.
The recess for the rail shall not be out of parallel with the plane of the base by more than 1mm per 100mm width of the base.
All edges shall be smooth, true and rounded to 2mm radius.
675.05IDENTIFICATION MARKS
Each casting shall be legibly marked, with a number or identification mark by which it can be traced to the cast and heat treatment batch from which it was made. All test samples, made in accordance with AS2074, shall be similarly marked.
675.06ACCEPTANCE OF SURFACE FINISH QUALITY BY VISUAL INSPECTION
Steel castings shall be visually inspected by the Contractor in accordance with AS3978 Non destructive testing - Visual inspection of metal products and components.
The texture and surface finish of all castings shall not exceed the following maximum levels of acceptable defect:
Surface texture / Level I : A1 / ASTM A802/A802M - 95
Nonmetallic inclusions / Level I : B1 / ASTM A802/A802M - 95
Gas porosity / Level I : C2 / ASTM A802/A802M - 95
Metal removal marks
Thermal
Mechanical
Welds / Level I : G1
Level I : H1
Level I : J1 / ASTM A802/A802M - 95
Hot tears and cracks / None acceptable / MSS SP55:2011
Shrinkage / Better than reference photograph a (TypeII) / MSS SP55:2011
Veining / Better than reference photograph a (TypeV) / MSS SP55:2011
Rat Tails / Better than reference photograph a (TypeVI) / MSS SP55:2011
Wrinkles, Laps, Folds and Coldshuts / Better than reference photograph a (TypeVII) / MSS SP55:2011
Scabs / Better than reference photograph a (TypeIX) / MSS SP55:2011
Chaplets / Better than reference photograph a (TypeX) / MSS SP 55:2011
Note 1:The maximum acceptable levels are consistent with surface discontinuity comparators for a reduced discontinuity size, as described in AS4738.1 (AppendixF).
Note 2:Sources of acceptance criteria are as follows:
●ASTM A802/A802M - 95 Standard Practice for Steel Castings, Surface Acceptance Standards, VisualInspection, ASTM(2006)
●MSS SP55:2011 Quality Standard for Steel Castings for Valves, Flanges and Fittings and Other Piping Components, - Visual Method for Evaluation of Surface Irregularities, Manufacturers Standardisation Society
675.07WORKMANSHIP
Where the maximum levels of acceptable defects as given in Clause675.06 are exceeded, the defects in the castings shall be rectified. Where appropriate, castings may be welded in accordance with the requirements of AS1988.1Welding of ferrous castings - Steel castings. After welding, all weldrepaired castings shall be given a stress relieving heat treatment.
675.08TESTING AND TEST CERTIFICATES
Testing for chemical composition and tensile properties shall be carried out for each cast or heat treatment batch. CharpyV-notch impact testing shall be carried out for the first batch cast, and then for at least every third batch. The Charpy impact average value, for testing of three specimens, shall be not less than the value nominated in AS2074 for the relevant grade.
Test certificates which demonstrate compliance of the steel with chemical composition and mechanical property requirements of AS2074 GradeC41 or GradeL1A cast steel, and the results of visual inspection shall be submitted to the Superintendent.
675.09PROTECTIVE TREATMENT
All cast steel posts shall be coated in accordance with the drawings and specification.