|
|
| |
INTRODUCTION:
Polyethylene is a thermoplastic Polyolefin material generated from the polymerization of ethylene. It is manufactured on a petrochemical basis with petroleum as the raw material. Depending of the polymerization process, different types of polyethylene materials are obtained. LDPE, with a density of 0.91 ̴ 0.93 g/cm³ is manufactured at very high pressure. While HDPE, with density of 0.94 ̴ 0.96 g/cm³ is manufactured at low pressure. Several modified copolymers have been developed in recent years. A recently developed grade, often termed as PE 100 with a density of 0.95 ̴ 0.965 g/cm³, has significantly higher strength properties than normal HDPE. It is especially designed for the production of larger diameter & thick walled pipe, but can be processed for the whole range of diameters. It also shows excellent resistance to rapid crack propagation and slow crack growth. |
|
|
Table 1 : Physical Properties of HDPE:
|
| Property |
Test
Method |
Units |
PE
80 |
PE
100 |
|
Density (Compound)
|
ISO 1183 |
Kg/m³ |
956 |
959
|
|
Melt Flow Rate(190ºC/5kg)
|
ISO 1133
|
g/10 min
|
0.3 |
0.25 |
|
Tensile Stress at Yield(50mm/min) |
ISO 527-2 |
MPa |
22 |
25 |
|
Elongation at Break |
ISO 527-2 |
% |
> 600 |
> 600 |
|
Charpy Impact Strength, notched |
ISO 179/1eA |
kJ/m² |
14 |
16 |
|
Carbon Black Content |
ASTM D 1603 |
% |
2 |
2 |
|
Vicat Softening Point |
ASTM D 1525 |
ºC |
118 |
122 |
|
Brittleness Temperature |
ASTM D 746 |
ºC |
< -70 |
< -70 |
|
ESCR (10% Igepal), F50 |
ASTM D 1693A |
Hrs. |
>10,000 |
>10,000 |
|
Thermal Conductivity |
DIN 52612 |
W/mºK |
0.4 |
0.4 |
|
Linear Thermal Expansion |
ASTM D 696 |
Kˉ¹ |
1.5x10ˉ4 |
1.5x10ˉ4 |
|
|
|
APPLICATION:
Pipes made of HDPE are flexible, strong, light in weight, highly resistant to UV radiation, impact resistant, and has more abrasion resistance than metal pipes. HDPE Pipe is non-toxic and extremely resistant to chemicals, solvents and radioactive waste water. It has become widely adopted in a variety of piping systems and rapidly replacing most conventional pipes. HDPE Pipes proved very successful in the potable water supply for domestic service lines, main schemes, sprinkler and drip irrigation systems, fire fighting networks, laboratories, industrial process lines, sewage and drainage, electrical conduit and many other applications.
QUALITY POLICY:
“It is the policy of Al Jubail Sanitary Pipe Factory (JSPF) to provide its customers High Quality HDPE/LDPE Pipes & Fittings as per DIN & ISO Standard, On-time delivery, and ever improving levels of customer satisfaction. JSPF is dedicated to continual improvement of its products, services and the company itself, through process control, employee empowerment and management commitment, in compliance with the requirements of ISO 9001:2000.”COLOUR OF PIPES: JSPF Pipes are normally supplied in black colour to counter attack Ultra-Violet Radiation and to suit extreme weathering conditions. Other colour like Orange PE Pipe is suitable for electrical conduit. A co-extrusion system was introduced lately to produce black pipe with colour stripes depending on pipe application. Blue stripe for potable water, Orange for electrical conduit and yellow for gas application.
|
|
|
|
DIMENSIONS:
All dimensions are expressed in metric units. The diameters of the pipes & fittings are measured in millimeters(MM) and represent the outside diameter of the pipe. To facilitate comparison of Metric to Inch range, a table of corresponding diameters is shown in
Table 2 |
|
MM |
16 |
20 |
25 |
32 |
50 |
63 |
75 |
90 |
110 |
125 |
160 |
200 |
250 |
315 |
355 |
400 |
450 |
500 |
630 |
| Inch |
3/8 |
1/2 |
3/4 |
1 |
1½ |
2 |
2½ |
3 |
4 |
5 |
6 |
8 |
10 |
12 |
14 |
16 |
18 |
20 |
24 |
|
|
|
CHEMICAL RESISTANCE:
High density polyethylene pipe offers a remarkable resistance to most of the Chemical Agents. It is unaffected by all kinds of water(drinking or waste), corrosive liquids, most common acids and alkalies, and all forms of corrosion normally encountered in metallic pipes. It is tasteless, odourless, non-toxic, and also can not be attacked by bacteria throughout its lifetime. Therefore it is a good choice for conveying drinking water and aqueous of foodstuffs.
THERMAL PROPERTIES
The water or any medium contained in polyethylene pipe changes temperature more slowly than in any other conventional pipe, because the thermal conductivity of this pipe is very low (0.43w/mºK). Also the chances of bursting the pipe are reduced by the ability of the pipe wall to take up expansion.
EFFECT OF ELEVATED TEMPERATURE:
The nominal working pressure has been calculated for operational conditions at 20ºC. Since Polyethylene is a thermoplastic material, a loss in mechanical properties is to be expected as the temperature rises. Where the system is to be operated at temperatures above 20ºC, then it must be reduced in respect of the maximum operating pressure & service life, details of which are shown in.
|
Table 3 : Working Pressure of HDPE Pipes at elevated temperatures as per DIN 8074-1999E.
|
|
|
|
Temp.
ºC |
Years of
Service |
Working pressure
in Bar |
Working pressure
in Bar |
Working pressure
in Bar |
Working pressure
in Bar |
|
|
|
PE 80 |
PE 100 |
PE 80 |
PE 100 |
PE 80 |
PE 100 |
PE 80 |
PE 100 |
|
20 |
50 |
4 |
4 |
6 |
6.3 |
10 |
10 |
16 |
16 |
|
30 |
50 |
3.3 |
3.3 |
5 |
5.3 |
8.4 |
8.4 |
13.5 |
13.5 |
|
40 |
50 |
2.9 |
2.9 |
4.3 |
4.5 |
7.2 |
7.2 |
11.6 |
11.6 |
|
50 |
15 |
2.2 |
2.3 |
3.4 |
3.7 |
5.7 |
5.9 |
9.1 |
9.5 |
|
60 |
5 |
1.8 |
1.9 |
2.7 |
3.0 |
4.5 |
4.8 |
7.2 |
7.7 |
|
70 |
2 |
1.3 |
1.5 |
2 |
2.4 |
3.4 |
3.9 |
5.5 |
6.2 |
|
| |
For further information, contact the technical support department
|
|
|
