Parliament Hinges -Specification
1991 Edition

IS 362 specifies materials for parliament hinges as follows: Cast brass hinges use Grade LCB 2 as per IS 292:1983. Hinges made from mild steel and aluminium alloy utilize mild steel sheets (Grade 0-1079 under IS 1079:1988) and aluminium alloy sheets (Grades 52000-H1 or 53000-H1 according to IS 737:1986). Extruded aluminium alloy components follow IS 733:1983 (Grades 63400 WP or 65032 WP) for rods and sections, and IS 1285:1975 (Grades 63400 WP, 65032 WP, or 64430 WP) for tubes and hollow sections. Additional parts like flap pins and wires have material specifications referencing IS 739, IS 280, IS 7608, and IS 4413, ensuring consistency and durability.

The dimensional tolerances for parliament hinges are detailed in Tables 2 to 4 of IS 362. For aluminium alloy hinges, width between flanges has a ±1 mm tolerance; cast brass hinges also have ±1 mm, while mild steel hinges have ±2 to ±3 mm depending on size. Length and width dimensions also have ±1 mm tolerance. Diameter of butt and pin, length of joint, and flap thickness follow tolerances as per IS 3965:1981 and IS 2525:1982. Screw hole numbers and sizes are fixed per hinge size, for example, a 50 mm hinge typically has 6 holes, whereas 100 mm hinges have 8. These precise dimensional controls guarantee proper fit and function.

For external use, aluminium alloy parliament hinges should be anodized, providing finishes such as bright, natural, matte, or satin, and can also be dyed. The anodic coating must meet or exceed Grade AC 25 as defined by IS 1868:1982, which is thicker and more protective than the minimum Grade AC 10 used for interior hinges. Additionally, hinges intended for outdoor settings must be permanently marked with the letter 'E' to denote their suitability for such environments, ensuring enhanced corrosion resistance and clear identification.

According to IS 362, hinge pins in brass parliament hinges are generally made from mild steel or brass, with phosphor bronze pins permissible upon purchaser request, especially in corrosive environments where brass or phosphor bronze is preferred. Aluminium alloy hinges use pins made from mild steel or aluminium alloy. The pins must fit securely within the knuckle, allowing smooth movement without looseness. Diameters vary by hinge size and material, with tolerances specified in the standard. Materials for wires and pins conform to relevant IS codes such as IS 4413 for brass wire, IS 7608 for phosphor bronze wire, IS 739 for aluminium alloy wire, and IS 280 for mild steel wire.

Conformity assessment in IS 362 involves defining a lot as hinges identical in type, size, material, and production conditions. Sampling is performed randomly according to the lot size, using sample sizes and permissible defectives listed in Table 5 (e.g., 13 samples with zero defects allowed for lots up to 150 hinges). Each sampled hinge is inspected for dimensional accuracy, manufacturing defects, and finish quality. If the number of defective units does not exceed the maximum allowed, the lot is accepted; otherwise, it is rejected. The sampling method follows IS 4905:1968. This process ensures statistically reliable quality control.