Recently, bucking bars made of tungsten have been utilized for some riveting tasks at a localaircraft manufacturer, where subjective reports from the employees suggested less vibration was transmitted to the hands.

However, since the tungsten bars weigh approximately 2.3 times more than the steel bucking bars of the same size and shape, the company was reluctant to implement tungsten bucking bars on a full scale. While the increased mass of the tungsten bar may be an advantage as far as dampening the vibration, the effect on the hand grip exertion levels was unknown.

Therefore, the overall objective of this study was to perform a field evaluation to quantify and compare the vibration transmission and gripmuscle activity characteristics when using bucking bars of the same size and shape, but made of different materials.While controlling for rivet size, air hammer,skin material, and bucking bar shape, the tungsten bucking bars resulted in a decrease transmission of vibration, with no difference observed for grip muscle activity. Thus, when access (i.e., clearance for the bucking bar and hand) dictates that the size of the bucking bar be used that was investigated in this study, it appears that the use of a bucking bar made of tungsten, which will have a larger mass than the traditionally used steel bars, may be useful in reducing vibration transmission and positively affecting the health and safety of the employees.

Tungsten Manufacturer & Supplier: Chinatungsten Online - http://www.chinatungsten.com
Tel.: 86 592 5129696; Fax: 86 592 5129797
Email: sales@chinatungsten.com
Tungsten Picture Center: http://picture.chinatungsten.com
Tungsten Video Center: http://v.chinatungsten.com
Tungsten News & Tungsten Prices, 3G Version: http://3g.chinatungsten.com
 

There are two forms of WC, a hexagonal form, α-WC (hP2, space group P6m2, No. 187), and a cubic high-temperature form, β-WC, which has the rock salt structure. The hexagonal form can be visualized as made up of hexagonally close packed layers of metal atoms with layers lying directly over one another, with carbon atoms filling half the interstices giving both tungsten and carbon a regular trigonal prismatic, 6 coordination. From the unit cell dimensions the following bond lengths can be determined; the distance between the tungsten atoms in a hexagonally packed layer is 291 pm, the shortest distance between tungsten atoms in adjoining layers is 284 pm, and the tungsten carbon bond length is 220 pm. The tungsten-carbon bond length is therefore comparable to the single bond in W(CH3)6 (218 pm) in which there is strongly distorted trigonal prismatic coordination of tungsten.

Molecular WC has been investigated and this gas phase species has a bond length of 171 pm for 184W12C.


Tungsten Manufacturer & Supplier: Chinatungsten Online - http://www.tungsten-carbide.com.cn
Tel.: 86 592 5129696; Fax: 86 592 5129797
Email: sales@chinatungsten.com
Tungsten Picture Center: http://picture.chinatungsten.com
Tungsten Video Center: http://v.chinatungsten.com
Tungsten News & Tungsten Prices, 3G Version: http://3g.chinatungsten.com

Positron emission tomography (PET) is one of the nuclear medicine techniques availablefor diagnosis.Whilst X-rays provide information on the structure of the body, PET shows the chemical function of a particular organism.  PET involves the injection of FDG (aglucose-based radio nuclide) from a shielded syringe into the patient. As the FDG travels through the patient's body it emits gamma radiation, which is detected by a gamma camera, from which the chemical activity within cells and organs can be seen. Any abnormal chemical activity may be a sign that tumours are present.

Tungsten alloy is ideal for shielding against both X- and Gamma radiation. The very high density of tungsten shielding (more than 60% denser than lead) allows a reduction in the physical size of shielding components, without compromising the effectiveness of the shielding characteristics.

Tungsten Manufacturer & Supplier: Chinatungsten Online - http://www.chinatungsten.com
Tel.: 86 592 5129696; Fax: 86 592 5129797
Email: sales@chinatungsten.com
Tungsten Picture Center: http://picture.chinatungsten.com
Tungsten Video Center: http://v.chinatungsten.com
Tungsten News & Tungsten Prices, 3G Version: http://3g.chinatungsten.com


 

Making spectrographic chemical analysis of tungsten carbide ball can be difficult and uncertain,  so the accepted procedure is to use a magnetic permascopic evaluation.

The same exactness of chemistry and physical properties in tungsten carbide ball that are experienced with alloy metals cannot be expected, as T.C. is made from a physical mixture of a pure metal powder and a powdered ceramic. There will naturally be more variability in performance.


Tungsten Manufacturer & Supplier: Chinatungsten Online - http://www.tungsten-carbide.com.cn
Tel.: 86 592 5129696; Fax: 86 592 5129797
Email: sales@chinatungsten.com
Tungsten Picture Center: http://picture.chinatungsten.com
Tungsten Video Center: http://v.chinatungsten.com
Tungsten News & Tungsten Prices, 3G Version: http://3g.chinatungsten.com