Frequently Asked Questions
  1. What is ISO 3633?
  2. What is ISO 161/1 Part I: Metric Series?
  3. What is ISO 3606?
  4. What is PN or Nominal Pressure?
  5. What does "Pipe Series" mean?
  6. What is "Design Maximum Induced Stress"?
  7. What is Thermoplastics?
  8. What is Polyethylene?
  9. What is a PVC-u or uPVC Pipe?
  10. What is a rework material? Is it permissible for use?
  11. What is a Vicat softening temperature?
  12. What material is the gasket seal made of?
  13. What happened to the old Moldex Plant? Is it still existing?
  14. Who is the pioneer in the Blue Pipes manufacturing?
  15. Is the solvent cement safe once it is exposed to the potable water?
  16. Why is your solvent cement too quick in drying?
  17. How do you price your product compared to your competitors?
  18. Is ASTM sizing (Inch series) wrong?
  19. Why is your price high compared to other brands?
  20. Why are the color of the pipes and fittings not the same?
  21. How do you explain the uneven outside diameters of your pipes?

What is ISO 3633?
ISO 3633 - This International Standards lays down the specification for PVC-u pipes and fittings, with normal outside diameters of 16mm to 400mm, intended for soil and waste discharge pipe lines (including the ventilation of these pipes) and internal rainwater pipes. (Adapted in the PNS 1950:2003)


What is ISO 161/1 Part I: Metric Series?
ISO 161/1 - Part I: Metric Series, This International Standards specifies the nominal outside diameters and nominal pressures of circular section thermoplastics pipes for the transport of fluids, whatever their method of manufacture, their composition and their use. It is intended to serve as guide to manufacturers and users, and as a basis for specific standards for thermoplastics pipes made from a given plastics material and/or for a definite application.


What is ISO 3606?
ISO 3606 - This International Standards applies to PVC-u pipes of circular section for the transport of fluids and specifies the perm issible deviations of the outside diameters and the wall thicknesses of pipes complying with ISO 161/I and ISO 161/II.


What is PN or Nominal Pressure?
PN or Nominal Pressure is the normal maximum internal pressure that the pipe can sustain in continuous use. This is expressed in megapascals (Mpa) at 28°C.


What does "Pipe Series" mean?
Pipe Series is used in classifying the pipe, which is the ratio of the design maximum induced stress to the nominal pressure of the pipe. The pipe series number may be rounded off to the nearest whole number.


What is "Design Maximum Induced Stress"?
Design Maximum Induced Stress is the estimated maximum tensile stress on yhe wall of the pipe along the transverse axis due to internal pressure to which the pipe can be subjected continuously without failure. This is used in calculating the wall thickness of the pipe. For the purpose of this standard, the maximum induced stress is 8.5 Mpa at 28°C.


What is Thermoplastics?
Thermoplastics - a plastic that can be repeatedly softened by heating and hardened by cooling through a temperature range characteristic of the plastic and that in the softened state can be shaped by flow into aticles by molding or extrusion.


What is Polyethylene?
Polyethylene is a polyme prepared by the polymerization of ethylene as the sole monomer.


What is a PVC-u or uPVC Pipe?
PVC-u or uPVC or Unplasticized Polyvinyl Chloride pipe is a pipe produced basically form an extrusion grade PVC material of high molecular weight which does not contain plasticizer.


What is a rework material? Is it permissible for use?
PVC plastics from a processors own production that has reground, palletized or solvated after having been previously processed. The use of manufacturer's own clean rework, material produced during manufacture and production testing of producs conforming to the standard is permissible. No other reworked material shall be used.


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What is a Vicat softening temperature?
A type of laboratory test for thermoplastic pipes wherein the softening temperature is measured through the use of a standard indenter, under a certain load (49.05 N force) and controlled increasing temperature. The temperature corresponding to 1mm penetration is called the Vicat Softening temperature (degrees Celsius).


What material is the gasket seal made of?
The gasket seal is made up of special Styrene Rubber and/or natural rubber that has good sealing properties, can withstand continuous vibrations and accommodate pipe movements during expansion and/or contraction.


What happened to the old Moldex Plant? Is it still existing?
All facilities and equipments from the old 3.5 hectares Valenzuela plant were transferred to a bigger (20 hectares) and better location in Marilao, Bulacan. The property still exists.


Who is the pioneer in the Blue Pipes manufacturing?
Freeman is the pioneer in the uPVC pipes (Caloocan City)


Is the solvent cement safe once it is exposed to the potable water?
Although solvent cement has active ingredients for the chemical fusion process, it is very safe after it is completely dried. Water contamnation is not a problem since pressure testing and flushing system after installation will remove unwanted remnants of the solvent cement. While the cured solvent cement shall be an integral part of the pipes and fitings and can no longer be a contaminant.


Why is your solvent cement too quick in drying?
Some plumbers prefer quick drying solvents for faster curing time and good joint fusion (complete cold weld). It is recommended that trial layout or dry fitting be practiced for best installation results.


How do you price your product compared to your competitors?
It has been our policy to give the customer satisfaction, aligned to this we make sure that our customers get the best value for the money. While others claim they are cheaper, they compromise quality and on most DWV sizes, they are undersized compared to Sanimold Extra.


Is ASTM sizing (Inch series) wrong?
Presently the inch series (ASTM sizing) is already in the phase out transition stage. The metric sizing is the standard of the future. The Philippines' direction, as per B.P. #8, is to shift from inch series to metric series. Therefore, The Bureau of Product Standards is compelled to adopt ISO 3633 thru PNS 1950:2003 and implement not later than year 2007.


Why is your price high compared to other brands?
It has been observed that other brands compromise quality in exchange for a lower price. Some brands have shorter lengths, smaller outer diameters, thinner walls and many have inferior materials. Moldex gives you the best value for your money, quality and your reputations are the prime considerations. In the long run, low maintenance, if not, no maintenance are factors that save money and reputation.


Why are the color of the pipes and fittings not the same?
Colors of the pipes ad fittings are dictated by colorant mixtures, but colorants or pigments do not affect the durability of the products. Color has acceptable color shade tolerances and differences may be noticeable to the customer. The pipes undergo extrusion process while the fittings undergo the injection moulding process. These are two different processes that can also affect the outcome of the color.


How do you explain the uneven outside diameters of your pipes?
This rarely happens to our pipes. Our production personnel, as well as our Quality Assurance inspectors should be able to detect these defects. MPI is commited to give you the best quality possible. If this is encountered, we are willing to replace those found beyond standard tolerances.


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