### What is the design criteria of Bolted Flange Plate Connection? Explain in details step by step procedure of a design of Bolted Flange Plate Connection with required formula and an example of calculation.

The design criteria for a Bolted Flange Plate Connection involve determining the required bolt size, bolt spacing, number of bolts, plate thickness, and flange dimensions to ensure the joint’s strength, stiffness, and integrity. Here is a step-by-step procedure for designing a Bolted Flange Plate Connection:

Step 1: Identify the Joint Requirements Determine the specific requirements of the connection, including the applied loads, desired safety factor, material properties, flange dimensions, and any applicable design codes or standards.

Step 2: Determine the Applied Loads Identify the loads that will be applied to the connection, such as tension, compression, shear, or a combination of these forces. Determine the magnitude, direction, and distribution of these loads.

Step 3: Select the Bolt Size Calculate the required bolt size based on the applied loads, material properties, and design codes. The formula to calculate the required bolt size is:

d = sqrt((4 * F * A) / (π * σ))

Where: d is the bolt diameter F is the applied load on the connection A is the tensile stress area of the bolt σ is the allowable stress of the bolt material

Step 4: Determine the Bolt Spacing Calculate the required bolt spacing based on the applied loads, plate thickness, and flange dimensions. The bolt spacing should be adequate to distribute the applied loads evenly across the connection and satisfy any spacing requirements provided by design codes or standards.

Step 5: Select the Number of Bolts Choose the appropriate number of bolts required in the connection based on the applied loads, desired safety factor, and design codes. The number of bolts should be sufficient to transfer the applied loads without exceeding the bolt or plate capacity.

Step 6: Determine the Plate Thickness Calculate the required plate thickness based on the applied loads, flange dimensions, and desired safety factor. The plate thickness should be sufficient to resist the applied loads without excessive deflection or deformation.

Step 7: Verify Joint Strength and Safety Perform a comprehensive design verification to ensure that the Bolted Flange Plate Connection meets the desired strength and safety requirements. This includes checks for bolt shear strength, bearing strength, plate strength, flange stability, and other connection details as per the design code provisions.

Example: Consider a Bolted Flange Plate Connection connecting two flanges with an applied tension load of 100 kN. The bolt material has an allowable stress of 300 MPa, and a safety factor of 2.0 is desired. The flange dimensions are known, and the bolt holes are evenly spaced.

Step 1: Identify the Joint Requirements The joint requires a Bolted Flange Plate Connection to transfer a tension load of 100 kN with a safety factor of 2.0.

Step 2: Determine the Applied Loads The applied load is a tension force of 100 kN.

Step 3: Select the Bolt Size Assume a bolt material with an allowable stress of 300 MPa. Calculate the required bolt diameter using the formula:

d = sqrt((4 * F * A) / (π * σ))

Assuming a standard bolt and using a safety factor of 2.0: d = sqrt((4 * 100 kN * 1.273 mm²) / (π * 300 MPa)) = 14.3 mm (rounded up to the nearest standard size)

Step 4: Determine the Bolt Spacing Select a suitable bolt spacing based on practical considerations, such as minimum edge distance and spacing requirements provided by design codes or standards.

Step 5: Select the Number of Bolts Choose an appropriate number of bolts required based on the applied load, desired safety factor, and design codes. For example, if using four bolts, the load per bolt would be 100 kN / 4 = 25 kN.

Step 6: Determine the Plate Thickness Calculate the required plate thickness based on the applied load, flange dimensions, and desired safety factor. The plate thickness should be sufficient to handle the applied load without excessive deflection or deformation.

Step 7: Verify Joint Strength and Safety Perform a comprehensive design verification, including checks for bolt shear strength, bearing strength, plate strength, and flange stability, to ensure that the Bolted Flange Plate Connection meets the desired safety and strength requirements.

Please note that this is a simplified example, and in actual design practice, it is essential to consider all relevant factors, consult with design codes or standards, and involve a qualified engineer to ensure a safe and efficient design.