Page 188 - Tyco-Grooved-Fire-Protection-Products-Installation-Handbook

186 SYSTEM DESIGN
To calculate the number of couplings required in this example to com-
pensate for the Thermal Expansion and Contraction of the pipe:
1) Thermal Contraction: Utilize the Thermal Expansion Table. Allow- ance for installation temperature to the minimum temperature, in this case 80°F to 40°F is calculated as:
80°F = 0.61 inches per 100 feet 40°F = 0.30 inches per 100 feet Difference = 0.31 inch per 100 feet
For 150 feet of pipe = 0.31 inch x 1.5 = 0.47 inch per 150 feet)
2) Thermal Expansion: Utilize the Thermal Expansion Table. Allowance for installation temperature to the minimum temperature, in this case 80°F to 200°F is calculated as:
200°F = 1.52 inches per 100 feet 80°F = 0.61 inch per 100 feet Difference = 0.91 inch per 100 feet
For 150 feet of pipe = 0.91 inch x 1.5 = 1.36 inches per 150 feet
3) Couplings Required: Available linear movement for a 6 inch Figure 705 Flexible Coupling on roll grooved pipe = 0.094 inch per coupling.
a) Fully Butted Together for Contraction Only
Therefore the number of flexible Figure 705 Couplings required: 0.47 inch / 0.094 inch per coupling = 5.0
Use 5 Figure 705 Couplings for pipe contraction.
b) Fully Gapped Apart for Expansion Only
Therefore the number of Figure 705 Flexible Couplings required: 1.36 inches / 0.094 inch per coupling = 14.47
Use 15 Figure 705 Couplings for pipe expansion.
Thermal Movement 3 of 4