New York Low Pressure Boiler COF Practice

When rolling and expanding tubes, how far should they extend?

1. 1/8", 1/4", 1/2"

2. 1/4", 1/2", 3/4"

3. 1/2", 3/4", 1"

4. 3/4", 1", 1 1/4"

The correct answer is: 1/4", 1/2", 3/4"

The correct choice indicates that when rolling and expanding tubes, the ideal extension should be in the range of 1/4 inch to 3/4 inch. This range is a standard practice in the industry, ensuring a proper fit and effective sealing between the tubes and headers. Effective rolling and expanding are essential for maintaining the integrity of boiler systems, as they help in preventing leaks and ensuring efficient operation. The dimensions provided in this answer are generally informed by the types of materials used, the sizes of the tubes, and the specific applications within low-pressure boilers. Inadequate or excessive extension can lead to insufficient contact or over-expansion, both of which can compromise the system's safety and functionality. Achieving a balance within this range is crucial for optimal thermal conductivity and mechanical stability. The other options suggest measurements that would either be too short or too long for typical applications, potentially leading to the aforementioned problems. Therefore, the selected range supports the common industry practices for effective tube connections.