Experimental Investigation on Mechanical Properties of Plastic Pipes Reinforced by Cross Helically Steel Wires

2008 ◽  
Vol 130 (2) ◽  
Author(s):  
Jinyang Zheng ◽  
Yubin Lu ◽  
Li Xiang ◽  
Xiufeng Lin ◽  
Yancong Zhu ◽  
...  

A Polyethylene (PE) pipe reinforced by a cross-winding steel wire (PSP) is a new type of plastic-matrix steel composite pipe, which has excellent performance. Its short-time burst pressure, strain, critical buckling pressure, and failure mode under various temperatures were investigated. Experimental results show that PSP has an increase of short-time burst pressure at room temperature up to 129%, ring stiffness up to 19%, and critical buckling pressure up to 57% in comparison with a comparable PE pipe. Failure modes of PSP subjected to internal pressure under various temperatures are found to be ductile burst and excessive deformation, and their transition temperature is about 45°C. Moreover, at the same pressure, the radial expansion ratio of PSP only bearing radial force is much larger than that of PSP bearing both radial and axial forces.

Author(s):  
Jinyang Zheng ◽  
Yubin Lu ◽  
Xiang Li

A plastic pipe reinforced by cross helically wound steel wires (PSP) is a new plastic-matrix steel composite pipe with excellent performance. Its strains, critical buckling pressure, short-time burst pressure and failure modes at various temperatures were investigated. Results show that its ring stiffness is increased by 19%, critical buckling pressure by 57% and short-time burst pressure at room temperature by 129% in comparison with a comparable polyethylene pipe; it has two failure modes, ductile burst and excessive deformation, and their transition temperature is about 45°C; radial expansion rate of the PSP due to internal pressure only exerting in the radial direction is much larger than that of enclosed PSP.


Author(s):  
KAKURO AMASAKA ◽  
HIROHISA SAKAI

It is necessary to establish higher levels of equipment reliability in a short time, the market demands ever shorter lead times for the release of new models. Also, the demand for new-model cars is very strong immediately after their introduction. The conventional method for enhancing equipment reliability is by screening alone. However, this requires screening operations on production lines and so has been an obstacle to line production and prevented shortening of lead times. We are now able to dramatically enhance equipment reliability in a very short time by detecting failure modes and forecasting the number of occurrences using a scientific technique based on reliability engineering.


Author(s):  
Zhanchong Shi ◽  
Qingtian Su ◽  
Xinyi He ◽  
Quanlu Wang ◽  
Kege Zhou ◽  
...  

<p>In order to solve the construction problem of perforating rebars’ precise location and it’s getting through the circular holes for the the conventional perfobond connector, a new type of perfobond connector with boot shaped slots was proposed. This new type perfobond connector has the advantage of convenient construction and pricise location. Three groups of push-out tests with nine specimens were carried out to study the shear capacity of the new type perfobond connector. The effect of the number and the spacing of boot shaped slots on failure modes, shear capacity, peak slip and shear stiffness were mainly studied. The test results show that the new type of perfobond connector with boot shaped slots has a high shear capacity and a good ductility, it could be widely applied on the connection between the steel and the concrete structures.</p>


2013 ◽  
Vol 823 ◽  
pp. 43-46 ◽  
Author(s):  
Feng Zhang ◽  
Zhi Fu Gao ◽  
Wu Hui Lu

Sprag overrunning clutch is one of key components in the drive system. Its a meaningful work to design and manufacture high performance sprag clutch to meet the practical working situation. In order to design reliable and durable clutch with good dynamic characteristics, this paper put forward a new type wedge surfaces which is a combination of involute and eccentric arc. On the basis of analysis of a clutch structure, work principles and failure modes, the sprag ,key element of the clutch, was demonstrated the feasibility of involute in the use of wedge surface design by analyzing the characteristics of involute, and the main sprag parameters were designed and analysized. The design of the new wedge surface, increasing the strut angle and effective cam rise, increased carrying capacity, reducing the contact stress, and extending service life, which laid the foundation for the sprag overrunning clutch design improvements.


Biologia ◽  
2015 ◽  
Vol 70 (1) ◽  
Author(s):  
Jakub Horak ◽  
Lenka Safarova

AbstractWetlands have recently become of high environmental interest. The restoration effects on habitats like fens are one of the main topics of recent restoration ecology, especially due to their interconnection with other ecosystems. We studied the manual mowing effect on abandoned fen using the response of three study taxa: diurnal butterflies, flower-visiting beetles and vascular plants. Our results showed that butterflies seems to be quickly-responding indicator taxon for evaluation and that restored management had a positive effect on both species richness and composition of this insect group. The results indicated that the manual mowing effect could be rapid. In comparison with the surrounding landscape, we found that: (i) the manually mowed site was most similar to strictly protected area, (ii) some species of high conservation value could reach higher abundance in restored than protected site, and (iii) manual mowing could bring a new type of habitat (i.e., spatial heterogeneity) compared to the other management types (abandonment, conservation and agri-environmental mowing). The main implication seems to be optimistic for practice: The manual mowing of long-term abandoned fen is leading to the creation of habitat with high conservation value in a relatively short time.


2012 ◽  
Vol 602-604 ◽  
pp. 2273-2278
Author(s):  
Ping Zhang ◽  
Jia Chun Li

As a new process, the abrasive belt grinding plays an increasingly important role in the field of machining. It meets a variety of processing requirements. The concept of abrasive belt grinding and its working principle were introduced, and a new type of abrasive belt grinding equipment for removing the rust on steel wire surface was designed. Some key experiments for testing grinding force,the metal removal rate,belt wear rate、grinding ratio,grinding depth and wire speed were studied. The research work provides rational parameters for the pretreatment of rust removal in metal wire drawing processing.


Synthesis ◽  
2020 ◽  
Vol 52 (22) ◽  
pp. 3427-3438
Author(s):  
Valery A. Ozeryanskii ◽  
Ekaterina V. Kolupaeva ◽  
Alexander F. Pozharskii

The reaction of 1-dimethylamino-8-(methylamino)naphthalene with 1,3-dibromopropane chemoselectively leads to the product of N,N′-heterocyclization, while in the case of 1,4-dibromobutane and 1,2-bis(bromomethyl)benzene the process results in heterocyclization onto the same nitrogen atom with the formation of previously unknown 1-dimethylamino-8-pyrrolidino- and 1-dimethylamino-8-isoindolino-naphthalenes. The same reactions conducted without adding any auxiliary base lead to the formation of N,N′-linked double proton sponges as a new type of polynitrogen organic receptor. Proceeding as a sequence of quaternization–demethylation–cyclization steps, this heterocyclization process can also be used to construct six-membered rings (piperidino, morpholino), albeit in lower yields. The ability of 1,2-dibromoethane to brominate N-alkylated 1,8-diaminonaphthalenes is also described. It is shown for the first time that a commercially available 1,8-bis(dimethylamino)naphthalene (DMAN) can be used as a starting material in a heterocyclization reaction, which via a one-pot approach and in a short time can be converted into 1,5-dimethylnaphtho[1,8-bc]-1,5-diazacyclooctane or 1-dimethylamino-8-(pyrrolidin-1-yl)naphthalene.


2019 ◽  
Vol 19 (11) ◽  
pp. 7315-7319 ◽  
Author(s):  
Yi-Xin Wang ◽  
Hong Tao ◽  
Min-Nan Chen ◽  
Ling-Shao ◽  
Guang-Feng Shang ◽  
...  

In this study, a new type of molecular sieve/polyacrylonitrile fiber (M-PAN) was prepared by electrospinning to adsorb atmospheric volatile organic compounds (VOCs). The suitable content of molecular sieve in nanocomposites was also determined for achieving maximum VOCs adsorption capacity. SEM, TEM and N2 adsorption/desorption analyzer were performed for characterization of the surface morphology, structural properties, surface area and pore size. A part of molecular sieve is exposed on the fiber surface where VOCs can be adsorbed efficiently in a short time. Acetone was used as a challenge pollutant to evaluate the adsorption of VOCs at different recycling times and types of electrospinning nanofibers. The adsorption capacity of 6M-PAN (60% weight of molecular sieve) nanofiber reached 58.2 μg g−1 and the reused nanofibers nearly had the same adsorption capacity as the newly prepared nanofibers after several times of recirculation.


2013 ◽  
Vol 37 (1) ◽  
pp. 129-134 ◽  
Author(s):  
Hai-Lin Zhu ◽  
Jun Pan ◽  
Min Zou ◽  
Hong-Nen Wu ◽  
Xingpei Qin

There exist three major problems in current gear pumps. They are unbalanced radial force, big excessive flow pulsation and short working life. In order to solve the problems above, a new type of gear pump with flexible ring gear is introduced. Pumping action is achieved through meshing between a flexible ring gear and a rigid external gear. Thus radial pressure forces are hydraulically balanced and the volumetric displacement is doubled for the new pump.


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