Victaulic System (PE-HD and PP)
Victaulic Jointing System uses standard steel clamps, requires only two fastening bolts and is easily and quickly installed. It is robust, with exceptional mechanical strength, economical and available in all standard popular sizes. Typical applications in pipelines are transportation of water, slurries, chemicals and air in Mining, Civil, Industrial and Agricultural/Irrigation sectors. Maximum service pressure for a Victaulic System is 1000kPa.
Takclamp System (PE-HD)
The Takclamp System is for use in the Gold Mining Industry. The Takclamp’s versatility is evidenced by its ability to handle vacuum conditions as well as pressure. Two types of Takclamp Systems are available: (1) High Pressure up to 1600 kPa service pressure and (2) Low Pressure up to 600 kPa.
Takstub and Takclamp System
Melt Flow Index Molecular Mass (MM)
A very important concept in plastics which describes the viscosity of a polymer and hence its flow and conditions for processing. A high MM has a more viscous melt and does not flow as easily as one with lower MM.
Melt Flow Index (MFI)
Generally used to categorize the molecular mass and is therefore a very important indicator of the type and properties of a polymer. MFI is determined as the mass of polymer extruded in a certain time through a standard die under a pre-determined load and temperature. Low MFI indicates that a polymer is very viscous and of a high MM. Lowering the MFI has the following positive effects on polymers by increasing:
• Tensile strength
• Elongation at break
• Impact resistance
• Resistance to creep
• Environmental stress crack resistance
It should however be noted that as MFI decreases the processing extrusion capabilities of the material are negatively affected.
The longer a polymer chain is, the more likely it is to be entangled with other chains and the more difficult to separate. In general terms then, it means that the tensile strength is increased.
Stiffness may be measured by applying tensile forces to a specimen. The result is tensile modulus or modulus of elasticity in tension.
Measured by finding the load required to indent a specimen by a standard amount with a spherical ball. Different scales are used, i.e. Shore, Rockwell and Brinell, respectively for softer to harder materials.
Many plastics, which are stiff and have high tensile strength, exhibit low impact resistance. This can be overcome to some extent with the addition of fillers, extenders or plasticisers, usually introduced during initial polymerisation, dosing or blending. It is also important to note that an increase in impact resistance effects properties such as stiffness, hardness and tensile strength. It is important to note, however, that the impact strength is increased at the expense of some other properties, such as stiffness, hardness and tensile strength.
A General rule in organic chemicals is that ‘like dissolves like’, e.g., a liquid hydrocarbon will dissolve a solid hydrocarbon of similar structure.