PVC Pipes - Temperature Expansion Loops
Calculate temperature expansion and contraction in PVC piping systems.
Temperature expansion and contraction in PVC piping systems can be compensated with
- expansion loops consisting of pipes and 90o elbows
- flexible bends
- bellows and rubber expansion joints
- piston type expansion joints
Expansion Loops
Expansion loops are made of standard pipes and elbows and can be produced on the site and adapted to the actual situation.
The length of the loop can be calculated as
Ll = ((3 E D δl) / (2 S))1/2 (1)
where
Ll = length of loop (in)
E = modulus of elasticity (psi)
D = outside diameter of pipe (in)
δl = change in pipe length L0 due to temperature change (in)
S = allowable working stress at maximum temperature (psi)
A = Ll / 5 (2)
B = 2 Ll / 5 (3)
Modulus of elasticity for PVC:
- 73oF : 400000 psi
- 100oF : 352000 psi
- 140oF : 280000 psi
Modulus of elasticity for CPVC:
- 73oF : 423000 psi
- 100oF : 385000 psi
- 140oF : 330000 psi
- 200oF : 241000 psi
Maximum working stress for PVC:
- 73oF : 2000 psi
- 100oF : 1240 psi
- 140oF : 440 psi
Maximum working stressfor CPVC:
- 73oF : 2000 psi
- 100oF : 1640 psi
- 140oF : 1000 psi
- 200oF : 400 psi
The temperature expansion of the pipe can be calculated as
δl = α Lo δt (4)
where
α = expansion coefficient (in/in oF)
Lo = initial length of pipe (ft)
δt = temperature change (oF)
Expansion coefficient for PVC:
- 28 10-6 in/in oF
Expansion coefficient for CPVC:
- 44 10-6 in/in oF
Example - Expansion Loop
A 2" PVC Schedule 40 straight pipe with outside diameter 2.375 inches and length 300 feet is installed at 70 oF and operated at 140 oF. The expansion coefficient for PVC is 28 10-6 in/in oF.
The expansion of the PVC pipe can from eq. 4 be calculated as
δl = α Lo δt
= (28 10-6 in/in oF) (300 ft) (12 in/ft) ((140 oF) - (70 oF))
= 7.1 inches
The modulus of elasticity is 280000 psi and the maximum working stress is 440 psi at maximum temperature. The length of the loop can from eq. 1 be calculated as
Ll = ((3 (280000 psi) (2.375 in) (7.1 in)) / (2 (440 psi)))1/2
= 126.5 in
A can be calculated from eq. 2 as
A = (126 in) / 5
= 25.3 in
B can be calculated from eq. 3 as
A = 2 (126 in) / 5
= 50.6 in
Related Topics
-
Temperature Expansion
Thermal expansion of pipes and tubes - stainless steel, carbon steel, copper, plastics and more.
Related Documents
-
ASTM D2241 - Poly(Vinyl Chloride) (PVC) Pressure-Rated Pipe (SDR Series) - Dimensions
Dimensions of PVC pipe SDR series. -
ASTM D2665 - Standard Specification for Poly(Vinyl Chloride) (PVC) Plastic Drain, Waste, and Vent Pipe and Fittings - Dimensions
PVC drain, waste, and vent pipe dimensions. -
ASTM D2729 - Poly(Vinyl Chloride) (PVC) Sewer Pipe - Dimensions
Dimensions of Poly(Vinyl Chloride) (PVC) Sewer Pipes with belled end. -
ASTM D2846 - CPVC Plastic Hot and Cold Water Distribution Tubes - Dimensions
Dimensions of CTS - Copper Tube Sized CPVC (Chlorinated Poly Vinyl Chloride) tubes. -
Copper Tubes - Expansion Loop Capacity
Capacity of copper tubes expansion loops. -
Copper, Ductile Iron, Carbon Steel, Stainless Steel and Aluminum Piping Materials - Temperature Expansion
Thermal expansion of typical piping materials. -
CPVC Pipes - Hanger Spacing
Maximum distance between CPVC pipe supports. -
EN 1452 - Unplasticized Poly Vinyl Chloride (PVC-U) - Dimensions
Dimensions of PVC-U pipe according EN 1452. -
ISO 161 - Thermoplastics Pipes - Dimensions
Dimensions of thermoplastic pipes according ISO 161. -
Pipes and Tubes - Temperature Expansion
Pipes expands when heated and contracts when cooled and the expansion can be expressed with the expansion equation. -
Piping Elbows - Thrust Block Forces
Thrust block forces on pipe bends anchors due to liquid velocities and internal pressures - online resulting force calculator. -
Piping Materials - Temperature Expansion Coefficients
Temperature expansion coefficients for materials used in pipes and tubes like aluminum, carbon steel, cast iron, PVC, HDPE and more. -
Plastics - Recycling Codes and Labeling
Symbol codes and labeling used for recycling plastic products like bottles, containers and packagin. -
Pressfit Pipes - Expansion Loops
Temperature expansion loops with pressfit piping. -
PVC Pipes - Equivalent Length and Pressure Loss in Fittings
Minor loss in PVC and CPVC fittings expressed as equivalent length of straight pipe. -
PVC Pipes Schedule 40 - Friction Loss vs. Water Flow
Water flow in thermoplastic PVC and CPVC pipes Schedule 40 - friction loss (ft/100 ft, psi/100 ft) and flow velocities at dimensions ranging 1/2 to 16 inches. -
PVC Pipes Schedule 40 - Friction Loss vs. Water Flow Diagrams
Friction loss (psi/100 ft) and velocity for water flow in plastic PVC pipe schedule 40. -
PVC Pipes Schedule 80 - Friction Loss vs. Water Flow
Water flow in thermoplastic PVC and CPVC pipes Schedule 80 - friction loss (ft/100 ft, psi/100 ft) and flow velocities at dimensions ranging 1/2 to 16 inches. -
Steel Pipes - Temperature Expansion
Calculate temperature expansion with carbon steel pipes. -
Steel Pipes - Thermal Expansion Loops
Calculating and sizing steel pipe thermal expansion loops. -
Thermal Expansion - Linear Expansion Coefficients
Linear temperature expansion coefficients for common materials like aluminum, copper, glass, iron and many more.
