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The Testing Times
The testing times is a blogspot from Tinius Olsen. It is a record of some of the interesting custom made testing products and gripping solutions which the Design Engineers have developed within Tinius Olsen.

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Tinius Olsen - Testing in Education
Friction "Pinch" testing of Hydrophilic Coatings on Catheters PDF Print E-mail
Tuesday, 12 January 2016 11:05



These days angioplasty or the placing of stents to widen and support archeries in the human body is almost considered a routine procedure, yet the technology behind it is exacting and subject to rigorous quality and performance control. Not only are the stents themselves as devices and the wire used in their construction tested for tensile, compression and stiffness properties so too are the catheters used to deliver the stent into the body through the small incision in the groin. In particular the frictional properties of the hydrophilic coating of the catheters outer surface must be qualified, know and controlled. At Tinius Olsen we have developed a system which accurately measures and plots the frictional forces developed between catheter and a known surface finish applied at a given and controlled “Pinch” force. The pinch force and defined surface finish provide the known parameters test after test, thus any variation in the friction measured is derived from variation in the catheter surface.

The test is a cyclic test with the catheter being subjected to the pinch force again and again, and as shown in the clip  Click Here the test is conducted within a saline environment, the solution being at body temperature.

The output from the Tinius Oslen system includes specific results; Friction force, time and position of the catheter as its cycles through the test process as well as graphs giving a graphical representation of the catheters performance. It is these results and graphs which qualify the quality and capability of a catheters surface coating.

Plastic Film Packaging PDF Print E-mail
Thursday, 16 July 2015 09:25

The plastic films & sheets market is typically segmented by packaging and non-packaging applications and is expected to grow at a very respectable pace during the coming decade. This growth is being fueled by the increased use of plastic film in food and pharmaceutical packaging and the Asia-Pacific region is expected to show the highest growth rate. Along with this expected demand is an increased expectancy of higher quality.

One such company that is gearing up to meet that demand is Premiaflex Plastics Limited (PPL) in Bangladesh. PPL is a major local manufacturer, supplying quality printed flexible packaging material using automated and sophisticated printing technologies for various forms of laminates with foil, film and paper. Their operations expanded rapidly to meet the ever growing needs of local market and due to their continuous upgrading and investment in machineries and manpower, they are at the first position for flexible packaging technology. Quality, together with consistency and reliability, are their primary values and to this end, not only have they added a third manufacturing line recently, but they have also invested in a new 5kN capacity materials testing machine from Tinius Olsen to monitor their process and product quality. Their preparations for growth, along with their commitment to quality, consistency and reliability, means that PPL will be able to meet the demands and tests of time in the future.

Quality Testing of Toothbrush PDF Print E-mail
Saturday, 04 July 2015 08:16

Tools for brushing teeth date back to 3500-3000 BC when the Babylonians and the Egyptians made a brush by fraying the end of a twig. Tombs of the ancient Egyptians have been found containing tooth sticks alongside their owners. Around 1600BC, the Chinese developed “chewing sticks” which were made from aromatic tree twigs to freshen breath.

The Chinese are believed to have invented the first natural bristle toothbrush made from the bristles from pigs’ necks in the 15th century, with the bristles attached to a bone or bamboo handle. When it was brought from China to Europe, this design was adapted and often used softer horsehairs which many Europeans preferred. Other designs in Europe used feathers.

The first toothbrush of a more modern design was made by William Addis in England around 1780 – the handle was carved from cattle bone and the brush portion was still made from swine bristles. In 1844, the first 3-row bristle brush was designed.

Natural bristles were the only source of bristles until Du Pont invented nylon. The invention of nylon started the development of the truly modern toothbrush in 1938, and by the 1950s softer nylon bristles were being made, as people preferred these. The first electric toothbrush was made in 1939 and the first electric toothbrush in the US was the Broxodent in 1960.

Today, both manual and electric toothbrushes come in many shapes and sizes and are typically made of plastic molded handles and nylon bristles. The most recent toothbrush models include handles that are straight, angled, curved, and contoured with grips and soft rubber areas to make them easier to hold and use. Toothbrush bristles are usually synthetic and range from very soft to soft in texture, although harder bristle versions are available. Toothbrush heads range from very small for young children to larger sizes for older children and adults and come in a variety of shapes such as rectangular, oblong, oval and almost round.

Quality Testing:
The basic fundamentals have not changed since the times of the Egyptians and Babylonians – a handle to grip, and a bristle-like feature with which to clean the teeth. Over its long history, the toothbrush has evolved to become a scientifically designed tool using modern ergonomic designs and safe and hygienic materials that benefit us all. To ensure that the modern toothbrush is robust and will withstand the multiple daily uses they’re designed for, manufacturers test toothbrushes for bristle strength, bristle abrasion and also for impact strength of the handle. The most common test standards used / complied to include impact standards ISO 179 (Charpy impact), ISO 180(Izod impact), ASTM D256 (Izod impact) and ASTM D6110 (Charpy impact) as recently confirmed by the latest purchase by one of the largest manufacturers of toothbrushes of a Tinius Olsen model IT504 impact tester.

Compression of Stonewool Insulation PDF Print E-mail
Thursday, 16 April 2015 10:51

Stonewool insulation is a mineral wool insulation product, manufactured from molten rock. It is a natural fibrous material, and has been widely recognized for decades for its thermal and sound insulating properties, as well as its excellent performance for the fire protection of lives and structures.  The use of technologically advanced machinery for the manufacture of stonewool insulation ensures stabilized production and superior quality final products.

Fibran SA, a part of the FIBRAN Group, produces stonewool insulation products with the brand name FIBRANgeo.  FIBRANgeo stonewool is produced from volcanic minerals such as basalt, limestone, dolomite, and bauxite. The minerals, as raw materials, are initially fused in an electric furnace and the vitreous melt is then spun into fibres. The maintenance of steady temperatures in the furnace enables the production of uniform stonewool fibres with excellent technical characteristics.  In addition, the levels of polluting sulfur and nitrogen oxide (SOX and NOX) gas emissions of the electric furnace are significantly lower than those of the blast method.


Once past the spinning phase, the loose stonewool fibres, with the addition of adhesive resin and special silicon compounds, acquire cohesiveness and hydrophobicity. Finally, FIBRANgeo stonewool Building Insulation products are formed in boards, rolls and loose fill in a variety of dimensions.  The above products may also be manufactured with facings. FIBRANgeo stonewool insulation products provide excellent thermal insulation, with a very low thermal conductivity coefficient and excellent thermal resistance even at high temperatures. The fibres’ softening temperature is over 1,000 °C and their binder starts to evaporate when its temperature exceeds 200 °C.  Therefore, FIBRANgeo stonewool insulation products are capable of withstanding high temperatures, up to 750 °C. These characteristics make FIBRANgeo products a perfect choice for thermal insulation, sound insulation and fire protection at construction projects.


At their headquarters in Greece, FIBRAN have added to their quality control testing lab with their recent purchase of a 10kN model 10ST tension and compression strength tester. The new machine will join their existing Tinius Olsen H10kT and model H10kS (seen here), and ensure consistent product quality.

Leaf and Coil Spring Testing PDF Print E-mail
Monday, 29 June 2015 08:31













The debate over which is better between leaf springs and coil springs has a long history. Coil springs have been around for nearly a hundred years, yet the leaf spring's history dates back well over a thousand, so both have long proven their individual merits, but which is better will always be a point of contention. The answer largely boils down to the intended use and for the automotive industry it boils down to this:

A leaf spring suspension is made of a series of long, relatively thin sections of springy metal attached at both ends to a frame and suspending the axle in the middle. Coil springs look just like you would imagine a spring should, and sit between the top of the axle, or lower control arm, and the chassis. In terms of function, leaf spring suspensions are much simpler, since the axle is suspended by the spring, and do not require the complicated suspension geometry of coil-spring set-ups. Leaf springs are also much sturdier, and are capable of handling much larger loads, with less deflection, than coils. Trucks with leaf springs, as an example, are also easier to raise or lower.


Coil spring suspensions offer more range of suspension movement, and allow the user a wider tuning envelope through the suspension range than leaf springs. Practically all high performance applications use coil springs where possible, and budget permits. Coil spring suspensions usually perform better, because they have better engineered geometry than leaf springs.

The leaf springs' simplicity is as much a curse as a blessing. Since these springs attach at fixed points on the chassis, they give very little room for adjustability of the suspension’s geometry. These springs also flex a great deal less than coil springs, resulting in a loss of wheel-to-ground contact under extreme conditions. The two main drawbacks to a coil spring suspension are cost and load-bearing. Cost isn't so much an issue, if the vehicle was originally equipped with coil springs, but retro-fits can be very expensive and time consuming. Coils are not generally favored for very heavy vehicles, as the coil on axle setup isn't nearly as stable or strong as a proper leaf spring.


For heavy, industrial or budget-limited applications, leaf springs will usually do an acceptable job and prove themselves a durable choice. However, there are very few applications which will benefit from leafs over coils where performance is concerned.

Fortunately for us, Supreme Springs in Gauteng, South Africa make both types of spring, as well as torsion bars and stabilizer bars for trucks and automobiles. We also know that the quality of these springs is superior because of their superior quality control programs; Supreme Springs has just invested in more tensile testers from Tinius Olsen, again at 50kN capacity, to ensure that Supreme Springs, whether they be leafs or coils, are at the top of their game.

Testing Extruded Polystyrene Insulation PDF Print E-mail
Wednesday, 15 April 2015 15:41

Polystyrene insulation is a type of rigid foam insulation which is commonly used in residential and commercial settings. It has an exceptional ability to insulate against noise and extreme temperatures, it is waterproof, and it has withstood the test of time. These qualities combine to make polystyrene insulation an exceptionally useful product.

As a thermoplastic polymer, polystyrene is in a solid (glassy) state at room temperature but flows if heated above about 100 °C, its glass transition temperature. It becomes rigid again when cooled. This temperature behavior is exploited for extrusion, and also for molding and vacuum forming, since it can be cast into molds with fine detail. Polystyrene (abbreviated to PS) is used for producing disposable plastic cutlery and dinnerware, CD "jewel" cases, smoke detector housings, license plate frames, plastic model assembly kits, and many other objects where a rigid, economical plastic is desired. Production methods for these products include thermoforming (vacuum forming) and injection molding.

Extruded polystyrene is suitable for a wide variety of applications, both in building construction and in industry, but primarily as thermal insulation due to its exceptional technical characteristics. Polystyrene from Fibran SA is produced with the use of environmentally friendly gases, and in accordance with the European requirements for sustainable materials and can be seen in their signature turquoise colour. Fibran uses extruded polystyrene to create a complete energy shield that protects against extreme temperatures and maintains its physical and chemical characteristics even after having been exposed to long-term loads and environments with increased humidity levels. FIBRANxps thermal insulation is supplied in boards as well as in composite prefabricated elements, combined with plain or water-resistant gypsum boards, white cement mortar and ceramic tiles.

To ensure continuing product quality, Fibran uses a 10kN Tinius Olsen dual column bench top machines to test the tensile strength, shear strength and compressive strength of their extruded polystyrene products and has recently increased their testing capabilities with the addition of a new model 10ST.


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