Page 36 - CPVC Fire Sprinkler Products Installation Instructions & Technical Handbook
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Thermal Expansion – Metric Units
TYCO CPVC Pipe, like all piping materials, expands and contracts with changes in temperature. The coefficient of linear expansions TYCO CPVC Pipe is: 0,062 mm/m/°C. The coefficient of linear expansion TYCO CPVC Pipe is the same for all pipe sizes.
To determine the linear expansion of the pipe due to thermal changes use the following formula:
∆L=eL(∆T) Where:
e = 0,061 mm/m C° (coefficient of linear expansion) L = Length of run in meters
∆T = Temperature change in °C
Example: How much will a 12 m run of DN20 TYCO CPVC Pipe increase in length (or expand) if the expected ambient temperature ranges from 2°C to 32°C? Changes in length due to fittings are insignificant relative to the pipe.
∆L=eL(∆T) ∆L=(0,061)x12x30 ∆L=22,0mm
TYCO CPVC exhibits a relatively high coefficient of thermal expansion (see Table H2). When designing TYCO sprinkler systems, expansion of long runs must be considered if temperature variations will be encountered (i.e., summer to winter extremes). Methods of compensating for thermal expansion are expansion loops, offsets and change of direction of the pipe run shown in Figure 7.
Loop Lengths “L” for use in Figure 7 are shown in Tables H2, J2, and K2. If the change in temperature and the maximum working temperature are lower than those used to derive the tables, the numbers will be conservative in nature. For example, for a temperature change from 16°C to 52°C use Table J2 because the maximum temperature is greater than those shown in Tables G2 and H2.
For conditions that are not covered in the Loop Length Tables, use the following formula:
L = Length of loop, offset, or charge of direction in millimeters
E = Modulus of elasticity at the maximum temperature (Table L2) in bar
D = Nominal outside diameter of pipe (Table D2) in millimeters
∆L = Change in length of pipe due to change in temperature in millimeters S = Working stress at the maximum temperature (Table L2) in bar

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