The 1983 specification details the criteria for manufacturing metal paper trays commonly used in offices and institutions. It outlines standards for materials, size, construction, finishing, and testing to guarantee strength and resistance to corrosion. This guideline is essential for producers, inspectors, and buyers aiming for consistent quality in steel and aluminum trays with specific welding and finishing requirements.
Overview
The 1983 specification details the criteria for manufacturing metal paper trays commonly used in offices and institutions. It outlines standards for materials, size, construction, finishing, and testing to guarantee strength and resistance to corrosion. This guideline is essential for producers, inspectors, and buyers aiming for consistent quality in steel and aluminum trays with specific welding and finishing requirements.
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This section defines the technical scope for metal paper trays, including the materials used, welding, and construction details. It emphasizes the purchaser's responsibility to provide technical information when placing orders (Clause 9). Welding must adhere to established Indian Standards such as IS 1323-1966T for aluminum alloys and IS 816-1969 for structural steel. Test results are to be rounded according to IS 2-1960 to maintain precision. Material references include hot-rolled and cold-rolled steel sheets and aluminum alloys.
Materials used include mild steel sheets conforming to IS 1079-1973 Grade 0 or IS 513-1973, with typical thicknesses like 0.315 mm for pressure testing. Aluminum sheets must meet IS 737-1974 H condition standards. Welding processes cover gas, arc, and spot welding as per relevant IS codes. Surface treatments involve phosphate coatings following IS 101-1964 and paint applications using enamel paints compliant with specified IS standards.
Metal paper trays must comply with dimensional tolerances of ±5 mm. Materials utilized are mild steel sheets meeting IS 1079-1973 Grade 0 or IS 513-1973. Welding standards referenced include IS 1323-1966T, IS 816-1969, IS 819-1957, and IS 2812-1964. All dimensions are measured in millimeters, with detailed layouts and knife edge specifics shown in the standard's figures.
Welding techniques for assembling trays must comply with IS codes relevant to gas, metal arc, and spot welding. Material specifications focus on mild steel and aluminum alloys for sheets and filler materials. Dimensions for test panels are specified, for example, 150 x 100 mm panels with 1.25 mm thickness for corrosion testing. Tests cover corrosion resistance and pressure endurance, ensuring no visible defects after testing.
Tray assembly requires welding of sides and bottom according to the prescribed methods in IS standards such as IS 1323-1966 for gas welding and IS 816-1969 for arc welding. Electrodes must conform to IS 1278-1972 and IS 814 (Part 2)-1974. Weld size guidelines specify throat thickness as 0.7 times the weld leg size, maintaining strength and quality.
Optional accessories include a spring clip installed inside the tray's shorter side to secure papers, if requested by the buyer. Welding for accessories must follow the same IS codes as the main assembly. Corrosion resistance tests apply to steel panels of specified dimensions and thickness, ensuring protective finishes meet standards.
Surface preparation involves phosphating of mild steel parts immediately after pickling, adhering to IS 3618-1966 Grade C and IS 6005-1970 code of practice. Finishing requires smooth, uniform coatings with minimum dry film thickness of 0.10 mm. Putty and primer materials must comply with IS 110-1968 and IS 5660-1970 respectively. Performance is verified through pressure and corrosion tests as detailed in IS 101-1964.
Finishes must be visually smooth and defect-free, hard, and resistant to chipping or flaking, with a minimum dry film thickness of 0.10 mm. Durability is assessed via pressure testing of 0.315 mm thick mild steel samples and condensation corrosion testing of 150 x 100 mm steel panels with 1.25 mm thickness, ensuring no degradation post-tests.
Purchasers must specify the desired color and finish of the trays, along with any alternative construction or finishing methods. Welding methods must align with IS standards. Corrosion protection requirements include passing condensation tests on specified mild steel panels, ensuring quality assurance.
Every metal paper tray must bear a mark identifying the manufacturer. Optionally, trays may display the ISI certification mark, which requires licensing under the Indian Standards Institution regulations. Marking facilitates product traceability and assures conformance with IS 3791.
Frequently Asked
As per the standard, steel sheets for paper trays must have a minimum thickness of 0.8 mm, while aluminium sheets should not be thinner than 1.0 mm. Additionally, the sheets must be free from burrs or dents, and the top edges are to be bent and pressed into a knife edge to ensure safety and a finished appearance.
The trays are to be assembled using welding methods including gas welding, arc welding, and spot welding. These processes must comply with specific Indian Standards such as IS 1323-1966 for gas welding, IS 816-1969 for metal arc welding, IS 819-1957 for spot welding, and IS 2812-1964 for tungsten inert-gas arc welding applicable to aluminium alloys.
The standard suggests using enamel paints that conform to IS 151-1950 (ready mixed paints and enamels), IS 2932-1974, or IS 2933-1975. The finish should be smooth, uniform, free from defects, hard, and possess a minimum dry film thickness of 0.10 mm to ensure durability and aesthetic quality.
Corrosion resistance is assessed by applying the specified finish to a mild steel panel measuring 150 mm by 100 mm with a thickness of 1.25 mm, then subjecting it to a condensation corrosion test as per Clause 18 of IS 101:1964. The panel must exhibit no signs of corrosion after testing to pass the evaluation.
The trays are dimensioned at 380 mm in length, 255 mm in width, and 65 mm in depth. While the standard does not explicitly state tolerances in the excerpt, typical manufacturing allowances are ±1 to 2 mm for length and width, and ±0.5 to 1 mm for depth to ensure proper fit and stacking capability.
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