VALDuotherm PP-R SDR6 pipe is used for indoor cold and hot water supply installations, as follows:
– Class 1 – hot water 60\u00b0C – PN 10 bar; design temperature related to service life: 60\u00b0C\/49 years + 80\u00b0C\/1 year + 95\u00b0C\/100 hours;
– Class 2 (hot water 70\u00b0C) – PN 8 bar; design temperature related to service life: 70\u00b0C\/49 years + 80\u00b0C\/1 year + 95\u00b0C\/100 hours;
– cold water PN 20 bar at c = 1.5 and PN 25 bar at c = 1.25 (Informative – In accordance with ISO 15874-1 – the design pressure for sanitary cold water installations for a period of 50 years at a temperature of 20\u00b0C is 10 bar).<\/p>\n
The linear expansion coefficient of single-layer PP-R pipes is \u03b1 = 0.15 mm\/m K, therefore before wall mounting (surface mounting) PP-R pipes, the effect of pipe expansion or contraction must be assessed. Correct installation of clamps or other types of supports and correct positioning of expansion compensators prevents uncontrolled pipe movement due to temperature variations during installation and operation. As a rule, system expansion is compensated between 2 fixed points by changing direction, an expansion loop, or where this is not possible, compensators must be fixed between the pipe and the structure. The fixing clamps (also called fixed points) of the system are positioned near branches, valves, or wall penetrations, and the sliding ones are installed along the route at well-defined distances. This ensures system alignment, support, and controlled axial movement. When installing PP-R pipes in screed or wall, they are installed in protective sleeves with a flexible structure, good insulation, and able to absorb pipe expansion. In the case of excessive expansion that is difficult to compensate with the protective insulating sleeve, an expansion compensator must be calculated and installed. Attention: pipes must be installed at an acceptable depth under the screed or inside the wall to avoid cracks; in addition, excessive internal stresses at joints must be avoided. The installation depth must be greater than or equal to 1.5 \u00d7 the pipe\u2019s outside diameter. Threaded joints are not permitted in screed or wall. The pressure test is carried out before the pipe\/system is permanently embedded. <\/p>\n
The technical manual covers methods for assessing expansion and ways to compensate for it, including clamp positioning.<\/p>\n","protected":false},"excerpt":{"rendered":"
For indoor cold and hot water
supply installations, as follows:
– Class 1 (hot water 60\u00b0C) – design temperature related to service
life: 60\u00b0C\/49 years + 80\u00b0C\/1 year + 95\u00b0C\/100 hours.
– Class 2 (hot water 70\u00b0C) – design temperature related to service
life: 70\u00b0C\/49 years + 80\u00b0C\/1 year + 95\u00b0C\/100 hours.
INSTALLATION
For PP-R pipes that are not installed embedded in a protective sleeve
(where expansion takes place within the sleeve) and for large-diameter
pipes, measures to compensate for expansion must be taken already at the
design stage.
PP-R pipes have the expansion coefficient:
– PP-R (alpha) = 0.15 mm\/m K,
– PP-R\/FIBRa (alpha) = 0.088 mm\/m K
– PP-R\/Al (alpha) = 0.03 mm\/m K.
For surface-mounted installation, the system must be secured
to prevent uncontrolled movement of the pipes.
Linear expansion is compensated between two fixed points. The system\u2019s fixed points
are positioned near
branches, valves, or wall penetrations.
Fixed points are positioned so that the expansion forces
The variation in pipe length depending on pipe length and
temperature variation is calculated using the following formula:
(delta)L = (alpha) x (delta)T x L (delta)L = L-Lo
(delta)T = T – To
where:
(delta)L = total variation in pipe length [mm]
(delta)T = total temperature variation
(alpha) = linear expansion coefficient, [mm\/m K]
T = operating temperature
To = installation temperature
L = pipe length at temperature T, [m]
Lo = pipe length at temperature To, [m]
Sliding points must be well secured to ensure
system alignment, support, and axial movement,
preventing vibrations and noise transmission. Calculation of the length
of the L-type expansion compensator
Where
Lb = length of the expansion arm, [mm]
d = pipe outside diameter, [mm]
(delta)L = total variation in pipe length [mm]
C = dimensionless material constant (C = 30 for PP-R)
PF: fixed point. PM: sliding point
Calculation of the U expansion compensator
The U compensator is an assembly of 2 L-type compensators, whose
length is calculated with the formula
above and the minimum width as follows:
Lc = 2 x (delta)L + ms,
Lc = minimum width of the compensator.
ms – safety width = 150 mm <\/p>\n","protected":false},"featured_media":97247,"template":"","meta":{"inline_featured_image":false,"wds_primary_product_brand":0,"wds_primary_product_cat":0},"product_brand":[],"product_cat":[8059],"product_tag":[],"class_list":{"0":"post-129309","1":"product","2":"type-product","3":"status-publish","4":"has-post-thumbnail","6":"product_cat-gray-ppr-pressure-pipes","8":"first","9":"instock","10":"shipping-taxable","11":"product-type-simple"},"yoast_head":"\n