The ability a material has to withstand rubbing and scraping. Our Ledaflex
tubing is a product that has a high level of abrasion resistance.
A rigid thermoplastic polymer common in piping applications.
ABS is very durable but breaks down when exposed to acetone.
Additive used to retard fungal growth in tubing, especially for applications in which
tubing is exposed to damp environments.
Additive used to prevent yellowing of tubing or loss of strength when exposed to
oxygen in the atmosphere.
A term used to describe the heating of a polymer to just below melting point. The
reconfigures the plastic molecules, re-setting the plastic's “memory.”
The temperature below which a flexible material exhibits brittle failure
when subjected to a specified impact during testing.
The minimum radius you can bend a tube or pipe without kinking it. It is measured to
the inside curvature of the tube.
The residue that, in time, comes out of plastics that contain plasticisers, stabilisers or
lubricants such as Vinyl (PVC). It is sometimes called a “haze.”
The pressure level required to burst a tube.
A joint in a plastic tube or tether that is created by melting two ends and then joining
end-to-end. The result is a bond as strong as the original material.
Coefficient of Thermal Expansion
The unit change in length or volume resulting from a unit change
A process of extruding two materials simultaneously through the same die.
Pigment additives used to introduce colour to tubing. Both natural coloured opaque
polymers and clear polymers can be coloured. Addition of colourant to clear polymers results in a
tinted transparent polymer.
A chemical blend of base resin and desired additives, which becomes the raw material from
which tubing is extruded.
Used to describe the uniformity of the wall thickness of tubing, it is a measure of
the offset of the centre of the inside diameter from the centre of the outside diameter.
Measured at constant stress and temperature, creep is a measure of deformation over time.
Creep always increases with temperature.
Any of the mechanical tests performed on an expendable sample of tubing to
check physical properties. These tests include tensile, yield, elongation, hardness, flare,
flattening, bend and burst.
The metal nozzle that the polymer is pressed through to create the tubing. The characteristics
of size, wall thickness and shape are dictated by the die that is used.
A measurement of the hardness of a polymer. It is usually measured using Shore or
Higher numbers represent harder materials.
The tendency of a material to return to its original shape after being bent or
The maximum amount, expressed as a percentage, that tubing can be stretched in length
before it breaks.
A material added to a polymer base that is designed to replace a portion of the polymer
compound. Also known as “filler.” Note Leda does not use extenders.
The thermal and mechanical process by which a polymer compound is conveyed through a
heating chamber, forming dies, cooling tanks and vacuum tanks to form tubing.
Fluorinated ethylene propylene, or FEP, is an alternative to Teflon tubing. (Teflon% is a
registered trademark of DuPont.) FEP tubing is known for chemical resistance and ability to
withstand a large range of temperatures.
An additive that is included in tubing compounds to improve resistance to burning.
The ratio of stress to strain that occurs while a stress is acting to bend an
object. Materials with lower flexural moduli tend to be more flexible.
The ability of a material to resist deformation under a load.
A polymer compound containing fluorine. These compounds are typically chemically
resistant and can withstand extreme elevated temperatures.
The ability to resist a change in physical properties under gamma irradiation.
Typically gamma irradiation is used in the plastics industry to sterilize tubing or process
components in an aseptic container. Commonly acceptable doses range between 25 kGy and 45 kGy
A compound that does not contain Fluorine, Chlorine, Bromine, Iodine or Astatine.
Halogenated compounds are often used to improve flame resistance of tubing, but when burned these
compounds emit smoke which is toxic to humans and corrosive to electronic equipment.
A measurement of resistance to surface penetration that correlates well with mechanical
strength and rigidity. Usually measured using Shore or Rockwell scales.
High Density Polyethylene.
Heat Deflection Temperature
a test in which a horizontal bar of a polymer is heated uniformly in a
closed chamber while a load of 66psi or 264psi is placed at the center of
the bar. The HDT is the temperature where a deflection of 0.25mm is reached at the center. The HDT
is an indicator of how much mass an object must be constructed of to maintain desired structural
integrity. Also, it provides a measure of rigidity of a material under a load at a certain
A non-destructive test procedure that checks for holes, cracks or porosity.
Tubing is pressurised internally with water to a high pressure, but does not exceed material yield
The inside diameter of a tubular product. It is also known as the opening or bore of a tube or
A trade mark of Arkema Chemical Corp. Kynar tubing is an economic alternative to Teflon when
heat resistance is not needed.
Low Density Polyethylene, typical density range of 0.910-0.940 g/cm3
Linear Low Density Polyethylene. LLDPE has very short chain branching form the polymer
compared to LLPE which has long chain branching. LLDPE typically has higher tensile and elongation.
The change in length, as opposed to the change in diameter, of heat
shrinkable tubing during the recovery process initiated by the application of heat.
Medium Density Polyethylene, typical density range of 0.926-0.940 g/cm3
A metric pressure unit and equals
to 1,000,000 force of Newton per square meter which is known as a Pascal. 1 MPa equals to 10 Bar.
Because of its high pressure ratings is often used in hydraulic and similar systems.
The tendency a particular plastic has to go back to its original shape after being
stretched or bent. Polyurethane is described as having excellent memory.
Modulus of Elasticity
The ratio of stress to strain that occurs when a stress is applied to a
material. While a stress is acting on a material a material, initially the relationship between the
applied force (stress) and the disturbance (strain) is linear (it is directly proportional), but
after the material is strained to a certain point, the relationship is no longer linear (this
phenomenon is known as Hooke‘s Law) .
The theoretical or stated value of a dimension
A stress acting perpendicular to a surface including compression and tension
A class of polymers known as polyamides. Nylon is a tough, abrasion resistant, semi-rigid
material with good high temperature properties. Leda manufacture tubing using Nylon 12 and Nylon
The outside diameter of a tubular product.
The maximum recommended temperature which tubing may operate in continuous
A quantitative measurement of how ‘round’ a tube is by comparing width to height.
The unit of pressure or stress equal to one Newton per square metre.
The capability a tube has for passing pressurized liquid or gas through its walls.
Esters of phthalic acid that are commonly used as plasticisers to soften and increase
the flexibility of PVC compounds. DOP/DEHP and DINP are two commonly used phthalate plasticisers.
It doesn't bond with the plastic so over time it may be released into the environment. There are
studies linking phthalates to a variety of ailments, particularly in children.
A compound that contains no intentionally added phthalates. Trace amounts of
phthalates may still be present.
A chemical additive that is included in polymer compounds to provide flexibility. It
is what is added to
PVC to change it from a rigid plastic used in pipe to a super flexible material for tubing.
Plasticisers serve to fill and increase the spacing between polymer chains,
allowing them to slip past each other more readily. Types of plasticisers include phthalates;
trimellitates; adipates; epoxidized vegetable oils, and polymerics.
A high impact thermoplastic resin used in making “bulletproof glass” and microwave
A large classification of resins that are used for making textile fibres. Not a tubing
A tough, flexible low cost plastic. Common applications are tubing, bags, film,
and squeeze bottles. Low-density polyethylene (LDPE) is the most flexible. Linear low-density
polyethylene (LLDPE) is the toughest and cheapest. High-density polyethylene (HDPE) is less
transparent, but stiffer and more heat resistant.
The generic word used to describe many plastics. Specifically, a polymer can be natural or
synthetic. The compounds are formed from many low molecular weight monomers that are combined into
long molecular chains.
Similar to high-density polyethylene, but more heat resistant (it can handle
boiling water) and having high tensile strength and clarity. It is noted for its rigidity and
resistance to chemicals. Common applications are plastic rope and drinking straws.
A highly resistant plastic that does not react to chemical
influences. It is most commonly known by its brand name, Teflon%.
A tough, abrasion resistant polymer having excellent low temperature properties and
high clarity. It is highly flexible and kink resistant. It is chemically resistant to fuels, oils
and solvents and is commonly used for fuel lines
and wire abrasion protection. It is available in both an ether and ester base. The ester-based PUR
is less desirable due to how it degrades in moisture. The ether-based polymer is much more durable.
Polyvinyl Chloride (PVC):
PVC tubing is made from a polymer that is tasteless, odourless and will
not degrade in most organic solvents. When a plasticiser is introduced, the compound becomes highly
flexible with good abrasion resistance. Does not break down the way rubber does.
Common flexible PVC applications are tubing and shower curtains. Common rigid or semi-rigid PVC
applications are drainpipe and house siding.
A compound consisting of long molecular chains formed from monomers occurring as
repetitive “building blocks”.
A generic term for a group of polymers produced from olefin (or alkene) monomers.
Olefins are hydrocarbon substances having a single carbon-to-carbon double bond. Polyolefin heat
shrink tubing is typically made from polyethylene and is usually cross-linked.
Common engineering abbreviation for pounds per square inch. It is a measurement of stress in a
material. 1 pound per square inch (psi) equals to 6,894.75729 Pascal.
The degree to which a plastic returns to its original shape after a load is removed.
The base raw material in a polymer compound. It is the term is used for the un-coloured
plastic pellets that we receive from our suppliers.
The length of a recoil tube when it is not in use. Also referred to as Closed
A durometer measuring scale developed by the Rockwell Corporation. Hardness is
measured by testing the resistance that a material has to being punctured. See “Durometer” and
The stress acting parallel to a surface
A series of scales used to indicate hardness (Shore A and Shore D). The Shore A
scale is most commonly used to measure the hardness of plastic tubing. Within a given scale, a
higher number indicates a harder material.
A plastic with high thermal stability, water resistance, flexibility and low toxicity.
Commonly used in medical tubing and cooking applications.
The ratio of the density (mass per unit volume) of a material to the density of
Any process that eliminates or kills all forms of microbial life, including
transmissible agents (such as fungi, bacteria, viruses, spore forms, etc.) present on a surface,
contained in a fluid, in medication, or in a compound such as biological culture media.
Sterilisation can be achieved by applying combinations of heat, chemicals, irradiation, high
pressure, and filtration.
A type of fitting that prevents a kink to form at the point where the fitting and
tube or hose meet.
Particularly useful in situations where the maximum working length of the tube is frequently met.
A measurable decrease in stress exerted by a material over time at a constant
A product of the DuPont Company, Teflon is a chemical and temperature resistant
The resulting deformation of a material due to tensile stress.
A measure of the ability a tube has to sustain tension (pulling).
Tensile Strength at Break (Ultimate Tensile Strength)
The force per unit area (psi or MPa)
required to break a material by applying a pulling force. It is a considerable factor in
calculating burst pressure.
A plastic that can be reshaped by heating and then sets when cooled.
A polymer that cannot be melted and reformed (commonly due to cross linking or
additives). In other words, thermosets thermally degrade before their melting temperature.
Thermoplastics can be melted and reformed.
The ability of a material to conduct heat energy. Thermal conductivity is a
physical constant for a measurement of heat energy that passes through a cube of a material in a
unit of time when the temperature of the two faces differs by 1 °C.
TPE (Thermoplastic Elastomer)
Thermoplastics that have characteristics similar to rubber. Unlike
rubber though, they can be repeatedly reshaped.TPU
also called polyurethane. A tough, abrasion resistant polymer having
excellent low temperature properties and high clarity. Chemically resistant to fuels, oils and
Thermal Plastic Vulcanite.
A polymer, such as polyolefin, in which irreversible chemical “curing” or “set” takes
place as the molecule chains are cross-linked in three dimensions through covalent bonding. Once
set, the polymer cannot be melted.
Tolerance (In Engineering)
The permissible limit of variation in units of measure
Total Organic Carbon (TOC)
A measure of bound carbon within an organic compound such as a plastic
The loss of strength or discoloration caused by long-term exposure of
tubing to sunlight or other ultraviolet rays.
Ultraviolet (UV) Stabilizer
An additive to tubing compounds that protects against loss of strength
or discoloration when it is exposed to the outdoors.
The resistance of a material to flow. Fluids that are highly viscous, are thick and
“gooey.” Water has a low viscosity.
A chemical reaction in plastic that occurs when exposed to sulphur, making soft
The length of a recoil tube when it is stretched to its maximum reach.
The maximum pressure at a given temperature, that tubing can be expected to
perform without sacrificing performance.