Tower Bolts - Specification: Part-1 Ferrous Metals

The scope of IS 204 Part 1 covers specifications for tower bolts including their dimensions, tolerances, and quality control sampling. Key tables include:

• Table 1 (Clause 5.2.1): Dimensions and tolerances for Barrel Tower Bolts, specifying sizes from 75 mm to 300 mm with details like length of bolt, barrel, width, diameter, socket length, sheet thickness, bore diameter, and minimum screw holes.

• Table 4 (Clause 5.2.4): Dimensions for Skeleton Tower Bolts, listing bolt length, plate dimensions, diameters, thickness, bore diameter, knob diameter, number of staples, and screw holes.

• Table 6 (Clause 10.2): Scale of sampling and permissible defective tower bolts based on lot size for quality conformity.

These tables define the physical and quality requirements for tower bolts under the standard. Tolerances and sampling criteria ensure manufacturing consistency and acceptance.

Example excerpt from Table 6 (Sampling):

Sources: Clause 5.2.1, Clause 5.2.4, Clause 6.1, Clause 10.2

Key references in IS 204 (Part 1): 1991 include detailed tables specifying dimensions and tolerances for tower bolts and related components, as well as sampling criteria for quality control.

1. Table 3 (Clause 5.2.3): Dimensions for riveted or spot welded tower bolts, including bolt length (A), bolt plate length (B), width (C), bolt diameter (D), socket length (E), strap length (E'), thicknesses (F, F'), bore diameter (G), and minimum screw holes. Tolerances are also specified.

2. Table 4 (Clause 5.2.4): Dimensions for skeleton tower bolts, listing bolt length (A), bolt plate length (B), width (C), bolt diameter (D), staple length (E), thickness (F), bore diameter (G), knob shank diameter (J), number of staples, and minimum screw holes.

3. Table 6 (Clause 10.2): Scale of sampling and permissible defective tower bolts based on lot size for conformity checks.

4. Annex A (Clause 2.1): Lists related Indian Standards referenced for materials and components, e.g., IS 210 for grey iron castings, IS 513 for cold rolled steel sheets, IS 6760 for wood screws.

These tables provide essential specifications for manufacturing, inspection, and quality assurance of tower bolts per IS 204 (Part 1).

Sources: Clause 2.1, Clause 5.2.3, Clause 5.2.4, Clause 10.2

As per IS 204 Part 1, Clause 3.1, tower bolts are classified into four main types with subtypes:

• Barrel Tower Bolts:

  • 1A: Mild steel barrel with mild steel bolt
  • 1B: Mild steel barrel with cast iron bolt

• Semi-Barrel Tower Bolts:

  • 2A: Full cover, mild steel pressed barrel and bolt
  • 2B: Full cover, mild steel pressed barrel and cast iron bolt
  • 3A: Open cover, mild steel pressed barrel and bolt
  • 3B: Open cover, mild steel pressed barrel and cast iron bolt

• Riveted or Spot Welded Tower Bolts:

  • 4A: Riveted type with back plate, mild steel bolt, open staple
  • 4B: Riveted type with back plate, cast iron bolt, open staple

• Skeleton Tower Bolts:

  • 5: Mild steel skeleton with pressed plate, staples, and mild steel bolt

Key dimensional tables include:

Table 2: Semi-Barrel Tower Bolts (Open and Full Cover)

Table 4: Skeleton Tower Bolts | Size (mm) | Length of Bolt (A) | Length of Bolt Plate (B) | Width of Bolt Plate/Staple (C) | Dia of Bolt (D) | Length of Staple (E) | Thickness of Plate/Staple (F) | Dia of Bore (G) | Dia of Shank of Knob (J) | No. of Staples | Min. No. of Screw Holes | |---|---|---|---|---|---|---|---|---|---| | 375 | 375 | - | - | - | - | - | - | - | 3 | 14 | | 450 | 450 | - | - | - | - | - | - | - | 3 | 14 | | 600 | 600 | 170 | 32 | 10.00 | 25 | 1.25 | 1 to 1.5 more than bolt dia | 5.0 | 4 | 16 | | 750 | 750 | - | - | - | - | - | bolt | - | 5 | 18 | | 900 | 900 | - | - | - | - | - | bolt | - | 6 | 20 |

All tower bolts shall be well made, free from defects, finished smooth, and for sheets 1.2 mm thick and above, have countersunk screw holes as per IS 6760:1972 (Clause 1.2).

This summary covers types, descriptions, and key dimensional tables for tower bolts as per IS 204 Part 1.

Sources: Clause 3.1, Clause 1.2, Clause 5.2.2, Clause 5.2.4, Table 2, Table 4

As per IS 204 Part 1:1991, Clause 4.1 and Table 5, the materials for tower bolts must comply with the following Indian Standard grades:

Additionally, Clause 10.5 requires the manufacturer to provide a certificate of compliance to these standards.

For dimensions of skeleton tower bolts, Table 4 (Clause 5.2.4) specifies sizes, lengths, diameters, and tolerances. For example, a 600 mm bolt has a bolt plate length of 170 mm, bolt diameter 10 mm, plate thickness 1.25 mm, and minimum 16 screw holes for wood screw No. 6.

These specifications ensure material quality and dimensional accuracy for tower bolts as per IS 204 Part 1.

Sources: Clause 4.1, Table 5, Clause 10.5, Clause 5.2.4, Table 4

IS 204 Part 1 (1991) specifies detailed construction and dimension tables for various types of tower bolts used in construction. Key tables include:

1. Table 1: Barrel Tower Bolts (Clause 5.2.1) with dimensions such as Length of Bolt (A), Length of Barrel (B), Width of Barrel (C), Diameter of Bolt (D), Length of Socket (E), Thickness of Mild Steel Sheet (F), and Bore Diameter (G). Minimum screw holes for wood screw No. 6 are also specified.

2. Table 2: Semi-Barrel Tower Bolts (Clause 5.2.2) with similar parameters plus specifications for open and full cover types.

3. Table 3: Riveted or Spot Welded Tower Bolts (Clause 5.2.3) detailing bolt length, plate dimensions, socket and strap lengths, thicknesses, bore diameters, and minimum screw holes.

4. Table 4: Skeleton Tower Bolts (Clause 5.2.4) specifying bolt length, plate dimensions, staple sizes, thickness, bore diameter, knob diameter, number of staples, and minimum screw holes.

All dimensions are in millimeters with specified tolerances. For example, bolt length tolerance is ±3 mm, bolt diameter ±0.5 mm, and plate thickness ±0.15 mm.

These tables provide comprehensive dimensional standards for tower bolt components ensuring interchangeability and structural adequacy as per IS 204 Part 1.

Sources: Clause 5.2.1, Clause 5.2.2, Clause 5.2.3, Clause 5.2.4

As per IS 204 Part 1, the dimensional tolerances for tower bolts are specified in Clause 6, with leading dimensions and tolerances given in four tables based on bolt type:

• Clause 6.1: Barrel tower bolts — see Table 1
• Clause 6.2: Semi-barrel tower bolts — see Table 2
• Clause 6.3: Riveted or spot welded tower bolts — see Table 3
• Clause 6.4: Skeleton tower bolts — see Table 4

Each table provides the key dimensions and permissible tolerances for the respective bolt type, ensuring standardization and interchangeability. For precise design or manufacturing, refer directly to these tables in the code.

Sources: Clause 6.1, Clause 6.2, Clause 6.3, Clause 6.4

For finishing in IS 204 Part 1, key specifications and dimensions for tower bolts are provided in detailed tables for different types of bolts: Barrel Tower Bolts (Clause 5.2.1), Semi-Barrel Tower Bolts (Clause 5.2.2), and Skeleton Tower Bolts (Clause 5.2.4). These tables specify dimensions such as length of bolt, length and width of barrel or plate, diameter of bolt, thickness of steel sheet, diameter of bore, and minimum number of screw holes for wood screws. For example, Table 1 (Clause 5.2.1) lists sizes from 75 mm to 300 mm with corresponding dimensions and tolerances. Additionally, Table 6 (Clause 10.2) provides the scale of sampling and permissible number of defective tower bolts for quality control during finishing. These tables ensure conformity and proper finishing of tower bolts used in construction.

Sources: Clause 5.2.1, Clause 5.2.2, Clause 5.2.4, Clause 10.2

As per IS 204 Part 1, Clause 8.1.1, tower bolts may be marked with the Standard Mark to indicate conformity to the standard. The Standard Mark assures compliance with the requirements under a defined system of inspection, testing, and quality control supervised by BIS. For sampling and conformity criteria related to tower bolts, Table 6 in Clause 10.2 specifies the sample size and permissible number of defective bolts based on lot size as follows:

This marking and sampling system ensures quality and conformity of tower bolts to IS 204 Part 1 requirements.

Sources: Clause 8.1.1, Clause 10.2, Table 6

As per IS 204 Part 1:1991, the packaging and labeling requirements are as follows:

• Clause 9.1: Barrel tower bolts must be packed in cartons. Each carton shall have a label indicating the source of manufacture or trade-mark, type, size, and quantity of bolts.

• Clause 9.3: Skeleton tower bolts should be wrapped in strong paper in bundles of 6 bolts each. Each packet or carton must bear a label showing the source of manufacture or trade-mark, type, size, and quantity of tower bolts.

• Clause 10.5: The manufacturer shall provide a certificate of compliance with the corresponding Indian Standard as per Table 5 (not provided in the context).

No specific formulas or tables for packaging and labeling are provided in the retrieved context.

Sources: Clause 9.1, Clause 9.3, Clause 10.5

As per IS 204 Part 1, Clause 10.2 and Table 6, the sample size for tower bolts depends on the lot size, and the permissible number of defective bolts is specified for conformity. The key table is:

Per Clause 10.4, a lot conforms if the number of defective bolts in the sample does not exceed the permissible number in column 3 of Table 6. Otherwise, the lot is non-conforming. Additionally, Clause 10.5 requires the manufacturer to provide a certificate of compliance with the relevant Indian Standard.

This ensures quality control by sampling and acceptance criteria based on lot size.

Sources: Clause 10.2, Table 6, Clause 10.4, Clause 10.5

The key Indian Standards referenced in IS 204 (Part 1):1991 as per Clause 2.1 Annex A are listed below in the table. These standards cover materials and finishes relevant to builder's hardware, such as castings, steel sheets, coatings, and screws. The manufacturer must provide a certificate of compliance to these standards for material conformity as per Clause 10.5.

This list ensures materials and finishes comply with recognized Indian Standards under BIS supervision.

Sources: Clause 2.1, Annex A, Clause 10.5