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Properties Method Units Typical value
Density ASTM D 1505 g/㎤ 0.954
Melt Index - 2.16 kg load ASTM D 1238 g/10 min 0.1
- 5 kg load g/10 min 0.56
Carbon black Content ASTM D 1603 % 2~2.5
Tensile Properties ASTM D 638(Ⅳ)
- Tensile strength at yield(min) kg/㎠ 230
- Tensile strength at break(min) kg/㎠ 300
- Elongation at break(min) % 500
Flexural modulus ASTM D 790 kg/㎠ 8800
Environmental Stress Crack Resistance ASTM D 1693 hr 1000
Condition B, F50(min)
Hardness(min) ASTM D 2240 shore"D" 63
Impact strength(Izod, Method A, min) ASTM D 256 kg㎝/㎝ 30
Brittleness temp.(min) ASTM D 746 ℃ -75
Vicat softening temp. ASTM D 1525 ℃ 123
Oxidative Induction Time at 200℃ ISO/TR 10837 min 40
Thermal conductivity ASTM D 177 Watt/m℃ 0.4
Coef.of linear theral expansion ASTM D 696 1/℃ 0.00013
Spesification data
- Material Classification ASTM D 1248 - Ⅲ C 5 P 34
- Cell Classfication ASTM D 3350 - 345434C(PE3408)


DAELIM polyethylene piping system is lightweight, flexible and chemical and abrasion resistant, allowing it to be used in a number of diverse applications. DAELIM PEM pipe is also protected from ultra-violet and thermal degradation, giving it a long service and storage life in above ground, exposed installations.
Material
DAELIM PEM water pipe is manufactured by TR-480BL black compound which contains 2 to 2.5% of finely devided carbon black and the additives. By the cell classification system of ASTM D 3350, TR-480BL is a PE 345434C which describes this compound as having the following primary properties (Referring to as "PE 3408" is a pipe material per traditional designation):

Property Cell Classification
Density, g/cm3(Base Resin) 0.941 - 0.955(cell 3)
Melt Index, g/10 min <0.15(cell 4)
Flexural modulus, MPa 758 - 1103(cell 5)
Tensile strenth @ tield, MPa 21 - 24(cell 4)
Environmental streess crack resistance, F20, hrs. min. Test condition C, 192hr.(cell 3)
Hydrostatic design base @23℃, MPa 11.03(cell 4)
Color & UV Stabilizer Code C(Black with 2% min. C/B)


Long Term Hydrostatic Strength
One of the outstanding engineering characteristics of DAELIM PEM pipe is its long term hydrostatic strength under various thermal and environmental condition. Life expectancy is conservatively estimated to be in excess of 50 years using the standard design basis. This strength is determined by standardized methods and procedures which the plastic pipe industry has used for many years to evaluate the long term strength of all types of plastic pipe.

Pipe hoop stress versus time to failure plots of long term hydrostatic pressure data for thermoplastic pipe have been studied and analyzed for many years. Pipe made from TR-480BL have been tested in order to estimate the long term hydrostatic strength, tests have been carried out at 20℃, 60℃ and 80℃ by using ISO/TR 9080 method. Stress-Life curves for TR-480BL are shown in Figure 1.

These stress-life curves were obtained using water as the test medium. However, years of laboratory testing and field experience have shown that these same curves may be used to design DAELIM PEM pipe systems for natural gas, salt water, sewage and hundreds of other industrial and municipal fluid, mixtures and effluents. The long term strength of TR-480 PEM pipe indicated by these curves must be derated in some environmental circumstances, such as in the presence of liquid hydrocarbons or abrasive fluids, although the pipe is very suitable for use in these environments.

An outstanding engineering advantage of TR-480 PEM pipe is its exceptionally long term service life in the presence of internal and external corrosive service conditions.
Design Pressure Ratings
The design pressures for TR-480 PEM pipe are determined by the following equation, adopted internationally by the industry for this purpose:



Table : Comparison between ISO and ASTM methods
Division ISO ASTM
бLTHS 50 years extrapolated values 11.5 years extrapolated values
бHDB MRS calculated by statical data(lower confidence limit) HDB obtained by catagorizing the LTHS in ASTM D 2837
бHDS бHDB ÷ C бHDB × F

Notes.
1. LTHS = long term hydrostatic strength
2. HDB = hydrostatic design basis
3. The design factor, F, has to a value less than 1.0.
4. The design coefficient, C, has to a value not less than 1.25.

The service design factor for Gas pipe line at standard temperature(20℃) is usually 0.32. The design factor for oil or liquid hydrocarbons is 0.25 at 20℃. The service design factor may be adjusted by the design engineer to reflect the particular conditions anticipated for the application. The temperature selected for design should consider both internal and external conditions. The design temperature should be based on the temperature of the pipe itself. For practical purpose, it is safer to design to the highest temperature.
Flow Factors
DAELIM PEM pipe has excellent flow characteristics as compared to traditional materials. An extremely smooth interior surface offers low resistance to flow. It maintains these excellent flow properties throughout its service life in most applications due to the inherent chemical and abrasion resistance of the material. Because of smooth walls and the non-wetting characteristics of polyethylene, higher flow capacity and less friction loss is possible with DAELIM PEM pipe. In many cases this higher flow capacity may permit the use of smaller pipe at a lower cost.

A 'C' factor of 150 is commonly used in the Hazen-Williams formula for calculating flow in pressure applications. For gravity flow, an 'n' factor of 0.01 is used in Manning's formula. Flow charts and additional system design information are available upon request.
Chemical Resistance
The outstanding resistance of DAELIM PEM pipe to attack by most chemicals makes it suitable to transport these chemicals or to be installed in an environment where these chemicals are present. Factors which determine the suitability and service life of each particular application include the specific chemical and its concentration, pressure, temperature, period of contact and service conditions which may introduce stress concentrations in the pipe or fittings.

DAELIM PEM pipe is, for all practical purpose, chemically inert within its temperature use range. This advantageous engineering characteristic is one of the primary reasons for the wide use of DAELIM PEM pipe in industrial applications. It is not an electrical conductor and does not rot, rust or corrode by electrolytic action. It neither supports the growth of nor is affected by algae, bacteria or fungi and is resistant to marine biological attack.

Gaseous hydrocarbons haves no advance effect on expected service life. Liquid hydrocarbons will permeate the wall and reduce hydrostatic strength but does not degrade the material. Upon evaporation of the hydrocarbon, the pipe will regain its original physical properties. Information relative to the resistance of DAELIM PEM pipe to a wide range of chemicals are available upon request.
Pipe Characteristics
Long Life
Life expectancy is estimated conservatively to be in excess of 50 years for transporting water at ambient temperature.

Fitigue Endurance
PEM piping systems provide exceptional endurance with the ability to sustain hydraulic transients and water hammer pressure surges.

Joint Integrity
PEM pipe can be hydrostatically tested to 1.5 times its designed pressure rating. All joints of butt fused PEM pipe are welded together to provide a continuous, non-gasketed pipeline which eliminates infiltration and exfiltration. PEM pipe also accommodates earth shifts and live loads from surface traffic without separation.

Toughness / Durability
PEM pipe will not break in heat or cold. Its impact resistance, slow crack growth resistance and service life prove it is the toughest pipe available for the toughest applications.

Lightweight / Flexibility
With DAELIM PEM pipe, fewer fittings are required and equipment handing requirements are significantly reduced.

Abrasion Resistance
DAELIM PEM pipe performs well in handing highly abrasive materials in low pressure-high velocity slurry systems. Controlled tests have shown that PEM pipe will generally out-perform steel pipe in this type of service by a ratio of 4 to 1. It also outlasts rubber lined steel in most slurry applications due to its smooth tough interior surface

Low Maintenance
A DAELIM PEM piping system force main pays for itself quickly because of lower energy costs, pipe longevity and overall reduced maintenance. In the water industry, DAELIM HDPE pipe continues to show the lowest level of service interruption.

Ease of Installation
DAELIM PEM pipe offers the following advantage as part of the installation process…lighter equipment needed, smaller crews, ordinary "bedding" requirements, standard valves and flanges. These benefits result in lower installation costs and a reduced number of fittings, with no restrained joints
Temperature Range
DAELIM PEM water piping system may be used in pressure applications up to an operating temperature of 60℃. Short term and gravity flow applications operating at high temperatures are considered. At lower temperatures, tests have been conducted on DAELIM PEM pipe showing that it gains strength at sub-zero temperatures. DAELIM PEM pipe maintains its flexibility and integrity to lower than -75℃.

The pressure capabilities of polyethylene materials are rerated for operating temperatures other than 20℃. TR-480 PEM pipe has been tested for thousands of hours at elevated temperatures without thermal degradation. These tests are used to obtain the pressure rerating factors.

Temperature(℃) Cell Classification
10 1.14
20 1.00
40 0.80
60 0.50
Applications
  • Potable Water
  • Coal Slurry
  • Marine
  • Drain Line
  • Taillng Disposal
  • Marinas
  • Fire Water
  • Fly Ash Disposal
  • Brine
  • Cooling Water
  • Sludge handing
  • Acid / Caustic Line
  • De-watering
  • Dredging
  • Sewer Treatment
  • Leachate Collection
  • Irrigation
  • Hazardous Waste
  • Aquaculture


Direct Burial
DAELIM PEM pipe is buried utilizing flexible pipe/soil system design practices. The pipe actually gains strength from the surrounding soil allowing it to support additional loads. Through proper pipe and backfill selection, PEM pipe may be buried at depths, in excess of 30 meters. At normal burial depths, according to the backfill of Standard Proctor density, the ring deflection of PEM pipe can limited to 2% of the original diameter.

Because PEM pipe can be butt fused above ground in long lengths, narrow trench widths can be used to save on installation costs. Due to the ease of handling PEM pipe, it may be readily placed in the trench, thus necessitating a minimum amount of open trench. Economics usually dictate maximum reuse of the excavated material. Where trenches are located within roadways and are subject to vehicular traffic, cohesionless, granular soils are generally specified. The best initial backfill material is sand. When loading conditions are severe, such as road crossings, sand should be used where the pipe is laid in low quality soils such as heavy gumbo or muck. Addition informations on trench and trench bottom, embedment materials, and bedding and installation practices are specified in ASTM D2321.
Installstion Procedure
  1. The trench bottom should be smooth and dry. It should also be free of any clumps of earth, large rocks or foreign materials. If the trenth is overexcavated, the void area should be filled with suitable bedding material as identified by ASDM D2321.
  2. The bedding should consist of 150 mm of well leveled embedment material compaction to 90% Standard Proctor Density. The trench bottom should be stabilized as necessary, before embedment material is placed, See table X 1.6 of ASTM D 3839 for embedment material recommendations.
  3. The initial backfill should be carried out in two steps, the primary and secondary backfill. Firstly, the primary backfill zone should normally extend to a height equal to 75% of the pipe diameter. If the pipe is placed below the water table, the primary zone should be increased 300mm to 600mm above the entire pipe. The following should be completed:

    • Compaction to 90% Standard Proctor Density.
    • Shovel material under pipe haunches.
    • Hand tamping is required around the haunches.
    • Backfill material should be put in evenly in layers not exceeding 300 mm and compacted in lifts.
    • Placement of the initial backfill will have the greatest impact on pipe deflection.

  4. The secondary backfill should normally be 150 mm to 300 mm above the crown of the pipe. The material protects the pipe during the final backfill. If the pipe is below the water table, additional height of material may be required to support against flotation. Compaction should be to 90% Standard Proctor density and care should be taken to prevent damage/deflection of the pipe when compacting.
  5. The final trench backfill should be of materials that meet engineering requirements and should be free of large stones and other foreign materials. Care should be taken to insure adequate compacted cover is obtained before any equipment is driven over the pipe.
Trench Cross Section


Butt fusion Welding - Joinign Procedure
The following equipment and services are needed :

  • Constant output electricity supply.
  • Butt fusion machine of suitable size, complete with electrically heated plate with temperature, and trimming tool.
  • Pipe support rollers.
  • Pipe cutter or fine toothed saw.
  • Cleaning material(paper towel or clean cloth).
  • External/internal debeading tool.
  • Bead gage.
  • Timer
  1. Read the operating instructions for the butt fusion machine and check all equipment is undamaged and in good working order. Inspect and clean the heater plate, removing any residue from previous welds(always carry out a dummy weld be for a weld proceeding).
  2. Switch on and retain the plate inside the thermally insulated protective case. Check and adjust plate temperature as necessary(210℃±10℃).
  3. Clean ends of components to be joined, inside and out.
  4. Open fully the machine carriage and place pipes to be joined in clamps to ensure free movement during welding.
  5. Align and level pipes in clamps using support rollers if necessary. Rotate as necessary to align orientation markings and then tighten clamps.
  6. Position the trimming tool in the machine. (Look at Picture 1)
  7. Switch on the trimming tool and close the carriage slowly.
  8. Hold the ends to be welded in contact with the rotating blade until continuous shavings are cut from the of both joining surface. (Look at Picture 2)
  9. While trimming continues, reduce carriage closing pressure to zero and the carriage is withdrawn.
  10. Remove the trimmer, taking care not to touch the planed surfaces.
  11. Remove shavings from the machine and pipe ends, again taking care to avoid contact with the trimmed surfaces.
  12. Check visually that both surfaces are completely trimmed.
  13. Bring pipe ends together, check for alignment and gaps. (Look at Picture 3)
  14. Minimise pipe end mismatch (max. 10% of pipe wall thickness) by adjusting clamps or pipe supports or by rotating pipe or a combination of both operations.
  15. If such adjustment is necessary, retrim and check again.
  16. Close the carriage and note drag pressure which is necessary to move the pipes.
  17. Consult the welding machine instructions for the fusion pressure recommended by the machine manufacturer for size of pipes to be welded. Add the respective pressure to the drag pressure to determine the 'applied pressure' during welding.
  18. Place the heating plate in the machine and close the carriage so that surfaces to be joined touch the plate. (Look at Picture 4)
  19. Apply the pressure previously determined in 17.
  20. When initial bead has reached the size of 2~3mm around each pipe end, reduce gage pressure to specified heat soak pressure (generally, initial bead width adds 0.5mm to 10% of pipe wall thickness). (Look at Picture 5)
  21. Keep the ends in contact with the plate for the time recommended by the machine manufacturer for the size of pipe to be weld. Timing starts from when the pressure is reduced (heating soak time is generally about 7 to 12 times of pipe wall thickness).
  22. When soak time is completed, open the carriage and carefully remove the heating plate-tapping to release it if necessary.
  23. Quickly close the carriage (within max. 8~12 seconds of removing the plate). Apply correct fusion pressure including drag pressure.
  24. Maintain the applied pressure for a minimum cooling time, as follows:
  25. 90 mm to 160 mm - 10 minutes
    180 mm to 315 mm - 15 minutes
    355 mm to 400 mm - 40 minutes
    (Look at Picture 6)
  26. The welded assembly can now be removed from the machine but should not be handled for a further period equal to the above cooling time.
  27. Examine the butt weld for cleanliness and uniformity. Check that the bead width is within the following empirical formulas:
    Min. bead width - 3 mm + 0.5 X wall thickness
    Max. bead width - 5 mm + 0.75 X wall thickness (Look at Picture 7)
  28. If it is necessary to remove either the external or internal bead from a butt weld, this can be done using special tools. Contact our Technical Services Department for futher information.

Electrofusion Welding - Socket Joinging Procedure
The following equipment and services are needed :
  • Constant output electricity supply.
  • Electrofusion control units.
  • Clamping equipment, including pipe and restraining clamps for all couplings and tapping tee clamps to suit the type to be welded.
  • Scrapers capable of scraping pipe ends or tapping tee surfaces so that 0.05~0.2 mm of pipe surface is removed, extending beyond the area to be covered by the fittings.
  • Cleaning material(paper towel or clean cloth).
  • Marker.
  1. Check that pipe ends are less than 2% pipe OD out of square to center line.
  2. Wipe loose dirt from pipe ends with clean, dry cloth.
  3. Arrange pipes to be joined so that they are approximately in line and with the ends touching.
  4. Using a marker or similar place a mark on each pipe approximately 20 mm outside the extremity of each end of the socket. (Look at Picture 8)
  5. Scrape the outer surface of each pipe completely(Do not touch the scraped pipe surface, fitting bore or saddle).
    ( Look at Picture 9)
  6. When using a hand scraper the operation is simplified by rotated the pipe and scraping from above. Where rotation is not possible scraping should start from the underside.
  7. In the case of mechanical surface preparation tools the instruction supplied by the manufacturers should be followed.
  8. After preparing the surface of both pipes care should be taken to prevent the surfaces from becoming contaminated by grease or other dirt. This can be conveniently achieved by placing a plastic bag over each pipe end. Place prepared pipe end in restraining clamp.
  9. Remove the fitting from the protective wrapping, and fit it onto of the pipes to which it is be joined until contact is made with the pipe center stop. (Look at Picture 10)
  10. 2 Tighten restraining clamps to minimize the risk of accidental movement and to assist in aligning pipes
    (Clamps must be used on all straight pipes above 180 mm OD to resist the forces generated by melt pressure).
  11. Start generator and connect the control unit input leads to generator output.
  12. Switch on the control unit.
  13. Connect leads from the control unit to the fitting terminals. And then follow the procedures which the manufacturer of the processor kit recommends (ie, fusion time, cooling time etc.). (Look at Picture 11)
  14. Disconnect leads from fitting. Clamping devices should remain in place to secure pipe and fitting during the recommended cooling time. After removing clamp, additional cooling time should be allowed before subjecting the joint to bending, burying, pressure testing, or similar handing and backfill stress.

Electrofusion Welding - Socket Joinging Procedure
  1. Clean joining surface with a clean cloth to remove any dirt or contaminates.
  2. Scrape entire pipe surface required for saddle fitting to remove oxidation and contaminants. For best results, secure tool on pipe and make two revolutions.
  3. Remove scraping tool and clean blade area with a clean, dry cloth. Repeat this procedure several times during the scraping operation to remove built-up of material.
  4. Continue scraping until surface material is remove and new material is exposed.
  5. Center fitting on pipe to determine required fusion area. Mark the pipe an equivalent length(Look at picture 12)
  6. Position saddle on freshly scraped surface with suitable clamping equipment(Do not touch the electrofusion surface of the saddle). (Look at picture 13)
  7. Follow the same fusion procedures used on the socket fitting(step 12 thru 14) to complete the saddle joint.
  8. Leads can be disconnected from the fitting and preparations made for the outlet connection. Clamping device should remain in place to secure pipe and fitting during the cooling period. Daelim recommends that the clamping device remain in place on saddle fitting throughout any punching or tapping operations that may be required.
  9. To make outlet connection, cut pipe end square and even. Clean pipe and outlet with a clean, dry cloth. Scrap pipe end and outlet to remove any oxidation or surface contaminants. (Look at picture 14)
  10. Again follow the same procedures used on the saddle fitting(steps 7~8) to complete the outlet joint.
  11. Do not attempt to "punch" the main until connection is properly cooled(Allow an additional cooling time before tapping the main with integral cutter or other approved device).
  12. To "punch" the main, remove the cap of the saddle fitting and insert the tapping tool. (Look at picture 15)
  13. A stop is provided on the tapping tool. Tapping tool should be bottomed out to the provided stop to assure a complete and proper "punch" has been achieved.
  14. Back tapping tool out to retune "punch" to its original position, flush with top of body. This must be done to assure "punch" does not restrict flow.
    (Look at picture 16)
  15. Cap should be hand tightened only. We do not recommended the use of wenches or other mechanical assist tools. (Look at picture 17)
  16. A protective sleeve can be slipped over the outlet of the tapping tee to reduce stress on the outlet connection.