Linear Expansions and Clamping

Linear expansion PPR Pipes

Pipe length ∆t 10 ∆ 20 ∆ 30 ∆ 40 ∆ 50 ∆ 60 ∆ 70 ∆t 80
m
0,5 0,75 1,50 2,25 3,00 3,75 4,50 5,25 6,00
1,0 1,50 3,00 4,50 6,00 7,50 9,00 10,50 12,00
2,0 3,00 6,00 9,00 12,00 15,00 18,00 21,00 24,00
3,0 4,50 9,00 13,50 18,00 22,50 27,00 31,50 36,00
4,0 6,00 12,00 18,00 24,00 30,00 36,00 42,00 48,00
5,0 7,50 15,00 22,50 30,00 37,50 45,00 52,50 60,00
6,0 9,00 18,00 27,00 36,00 45,00 54,00 63,00 72,00
7,0 10,50 21,00 31,50 42,00 52,50 63,00 73,50 84,00
8,0 12,00 24,00 36,00 48,00 60,00 72,00 84,00 96,00
9,0 13,50 27,00 40,50 54,00 67,50 81,00 94,50 108,00
10,0 15,00 30,00 45,00 60,00 75,00 90,00 105,00 120,00

Linear expansion of Fiber Pipes

Pipe length ∆t 10 ∆ 20 ∆ 30 ∆ 40 ∆ 50 ∆ 60 ∆ 70 ∆t 80
m
0,5 0,25 0,50 0,75 1,00 1,25 1,50 1,75 2,00
1,0 0,50 1,00 1,50 2,00 2,50 3,00 3,50 4,00
2,0 1,00 2,00 3,00 4,00 5,00 6,00 7,00 8,00
3,0 1,50 3,00 4,50 6,00 7,50 9,00 10,50 12,00
4,0 2,00 4,00 6,00 8,00 10,00 12,00 14,00 16,00
5,0 2,50 5,00 7,50 10,00 12,50 15,00 17,50 20,00
6,0 3,00 6,00 9,00 12,00 15,00 18,00 21,00 24,00
7,0 3,50 7,00 10,50 14,00 17,50 21,00 24,50 28,00
8,0 4,00 8,00 12,00 16,00 20,00 24,00 28,00 32,00
9,0 4,50 9,00 13,50 18,00 22,50 27,00 31,50 36,00
10,0 5,00 10,00 15,00 20,00 25,00 30,00 35,00 40,00

Heating the pipes, one should take into consideration the coefficient of linear expansion of the product. In the plastic materials, it is higher than the one of metal materials.

For systems in the walls, these values should not be considered, as expansion is absorbed by the product self. In the graphic example, different kinds of material for pipes and fittings have been taken into consideration.

The same temperature and piping length has been considered, to compare the different linear elongation.

 

The linear expansion can be calculated also through the following formula; Dl = α * L * ∆t

Meaning: Dl = linear elongation in (mm)

α = coefficient of linear elongation

Pipes (mean value) = 0.15 mm/mK

Pipe Fiber and pipe with metal shell (mean value) = 0.05 mm/mK

L = pipe length in m

∆t= difference of temperature between warm water and room temperature.

 

Example no.1: linear expansion calculation

Data: α = 0.15 mm/mk

L = 6 m

∆ t = 40°C

Calculation: α * L * ∆ t = Dl

0.15 * 6 * 40 = 36 mm

To avoid the linear movements of the brackets for the PP-R pipes in free laying and in case it is necessary, SupraTherm suggests to use the zinc-plated steel shells, available for all the diameters of pipes produced and sold. This accessory reduces the PP-R expansion and prevents the formation of bad bending on the piping, above all in case of warm fluids conveyance and/or where temperatures affect the pipe bending (for ex. industrial buildings, shafts, thermal power station).

 

Processing:

1) Refer to the table “Clamping with support bracket for pipes, with metal shell”.

2) Fix the support bracket of the pipe (with rubber protection for warm fluid).

3) Instal the pipes on the support brackets.

4) Put the shell on, taking care that length is in coincidence with both the support points and, if necessary, cover with insulating sheath according to law.

 Clamping (in cm)

∆t Ø 20 mm Ø 25 mm Ø 32 mm Ø 40 mm Ø 50 mm Ø 63 mm Ø 75 mm Ø 90 mm Ø 110 mm Ø 125 mm
20°C 60 75 90 100 120 140 150 160 180 200
30°C 60 75 90 100 120 140 150 160 180 200
40°C 60 70 80 90 110 130 140 150 170 190
50°C 60 70 80 90 110 130 140 150 170 190
60°C 55 65 75 85 100 115 125 140 160 180
70°C 50 60 70 80 95 105 115 125 140 155

Table of clamping of the Alufoil pipe

∆t Ø 20 mm Ø 25 mm Ø 32 mm Ø 40 mm Ø 50 mm Ø 63 mm Ø 75 mm Ø 90 mm Ø 110 mm
20°C 120 130 150 170 190 210 220 230 250
30°C 120 130 150 170 190 210 220 230 240
40°C 110 120 140 160 180 200 210 220 230
50°C 110 120 140 160 180 200 210 220 210
60°C 100 110 130 150 170 190 200 210 200
70°C 90 100 120 140 160 180 190 200 200

Table of clamping of the Fiber Glass pipe

∆t Ø 20 mm Ø 25 mm Ø 32 mm Ø 40 mm Ø 50 mm Ø 63 mm Ø 75 mm Ø 90 mm Ø 110 mm Ø 125 mm
20°C 100 105 120 130 150 160 180 190 200 220
30°C 90 100 115 125 145 155 175 185 195 210
40°C 85 95 110 120 140 150 170 180 190 205
50°C 85 90 105 115 135 145 165 175 180 195
60°C 80 85 100 110 130 140 160 170 175 185
70°C 70 80 95 105 125 135 155 165 170 175

 

Introduction For a correct installation, you should not block the pipe expansion, both in radial and in coaxial direction. Useful is to compensate the movement by setting fixed points, sliding clamping and dilatation breaks. Clamping should always be done depending on the pipe diameter; the material for clamping should not damage the outside surface of the pipe (to this aim, use brackets with rubber protections or similar). Sliding supports This installation should allow the axial movement of the pipe, without damaging it. The pipe movement should not be blocked by any shaped piece. To calculate the support distance, refer to the given diagrams. Fixed points

841001The fixed points (FP = Fest Punkte) prevent the unexpected pipe movements and divide them into single parts of linear expansion. By arranging the fixed points, one should consider all the forces acting on the pipe contemporary (linear expansion, weight of material, fluid and further loads). The fixed points should be stronger than a support; we suggest to arrange them always by branches or closing devices. You can also choose where arranging them: in this case, they should be set where the pipe direction changes, to absorb the linear expansion.