This study includes a work to improve the performance of brake shoe which is used in rail, where it depends on heat treatment to brake shoe which is made of gray cast iron, which makes the occurrence of the largest dissolve of the carbon in austeni
te. It allows obtaining a new crystalline structure of cast iron which has high toughness and high wear resistance. It increases the life service of brake shoe, and increases safety factor on rail way.
The test results were compared to the heat treated samples with samples that were not subjected to heat treatment, and treatment processes gave good results that allow to apply these operations on bits currently used on the railway network in Syria.
The aim of this research is to study the absorptive effect of high density (HDPE) polyethylene pipes for the hydrocarbon compounds on the characteristic (Force, Elongation) curves. To verify this, we immerse some parts of the pipe in different hydroc
arbon mediums containing gasoline, diesel, and motor oils of (10 and 40) calibre. The result show that these compounds have a bad effect on the submission force, neck formation, and damage force. The experimental results also show that motor (engine) oils have a similar effect on gasoline despite low absorption percentages.
The implantation of production processes by using network planning for mass
production is considered essential in machine production and maintenance . This is more
important when producing items as an integrated project that has to be finished in s
pecific
time and with last cost. The network planning is seen from a new perspective because it
studies reaction method and response method to incidental (emergency) events in industrial
production such as ( machine malfunction, shortage in raw materials…) This study uses
probability methods which considers all previous factors when calculating the critical path
in Network plans.
The new approach of this research is using Network planning for programming
production processes in mass production especially in maintenance processes.
This experiment investigates the effect of aluminum powder as metallic filler of
unsaturated thermosetting polyester resin on the wear rate and its mechanisms according to
time.
The obtained results show that the rate of wear increases with increa
se of time as a
result of increase the temperature generated of friction in all specimens. But when we add
the particles either Aluminum to polyester matrix, the rate of wear reduce as a result of
increase the thermal conductivity of polyester matrix, that leads reduction of the
temperature of contact surface, that leads less wear. We study the mechanisms of wear by
microscope of the worn surface. It found that the predominant mechanisms of wear vary
from adhesive wear at the lowest value of test time to abrasive wear (3- body) at the
highest value of test time.
It is a cross in the hydraulic systems with long pipes case modeling of the hardest and most important cases in search. Of the most important and is considered Query to achieve study the changing resistance model is used to describe the changing liqu
id flow in the tube. As described by knowing the nature of the shear stress to the pipe wall and also know the nature of the flow ( laminar or turbulent ). The results of simulations of hydraulice shock caused by the sadden move of the hydraulic control valve which studied in the following cases:
1- Hard to improve the discharge of the pump rate.
2- Improve the discharge of the pump variable rate finally; compare the results of computer simulations with experimental results.
As a result of the development of the use of reinforced Composites with fibers in
practical applications continuously, research aims to study the effect of proportion piroxide
additives to unsaturated polyester resin on the tensile properties of th
e samples prepared
from unsaturated polyester resin reinforced with glass fiber used in wind turbine blades
manufacturing, and also studying the effect of for the application of heat treatment
operations on the hardening of the unsaturated polyester and tensile properties after heat
treatment process the application in order to improve the properties of these blades.
Test samples were prepared containing ratios (1% - 1.5% - 2%) of methyl Etel
ketone piroxide MEKP and test results showed that the best ratio at 1.5%. While the heat
treatment results showed that the best values for tensile strength at break of the samples are
treated to a time of / 48 hours /.
This research aims to study the effect of adding inorganic waste (Marble powder -
glass powder) on the volumetric and longitudinal shrinkage curves at unsaturated polyester
resin, tests showed that samples exposed to volumetric and longitudinal shr
ink and
occurrence of consecutive gradients in volumetric shrinkage values. Whatever the ratio of
the added materials (marble powder - the glass powder) will effect the behaviour of the
unsaturated polyester hardening, that means it will effect the volumetric shrinkage.
It is necessary to study the volumetric and longitudinal shrinkage values because
they affect the product size to be dealt with, this value should be taken into account in the
design so that should be added this amount of volumetric shrinkage to the dimensions to
designed templates in order to avoid potential variations occurring in the final product.
Preliminary results showed that the value of volumetric shrinkage got up (5%) and the
curves tend to stability, almost three weeks after the initial hardening incident.
أجبرت المنافسة المتزايدة في الأسواق العالمية الشركات الصناعية على السعي لتطـوير
طرق العمل المتبعة، و ذلك من أجل تحقيق الاقتصادية المنشودة مـن العمليـة الإنتاجيـة
و تحسين مستوى جودة المنتج. أيضاً أثر تعدد الشركات المنتجة للمنتج نفسه في تسـريع
وتيرة
تطوير طرق العمل، و ذلك من أجل البقاء في الأسواق و البقاء ضمن دائرة المنافسة.
تعد الدراسات التحليلية طرق العمل من أهم المواضيع المطروحة على الصـعيد البحثـي
العملي في الشركات الصناعية، و ذلك سعياً للوصول إلى الجودة المثالية للمنتجات (أعلـى
درجة إقبال على الشراء مع أقل تكاليف ممكنة) . لذلك تم استعراض المفاهيم المختلفـة
لطرق العمل مع استعراض طرق و وسائل تطوير طرق العمل، مع توضيح الأسباب التي
تستدعي اتخاذ الإجراءات اللازمة للبدء في تطوير طريقة العمل المتبعة. إن السعي وراء
تطوير العمل سببه الـتأثيرات الاقتصادية الإيجابية الناتجة عن تخفيض التكاليف و ازدياد
الطاقات الإنتاجية و تخفيض زمن العملية الإنتاجية و تقليل عدد العمال .
The increasingly growth of population led to an increase in the number of
different industrial plants and to arise in their productive capacity which led
to the formation of large quantities of waste products in their gas, liquid and
solid forms.
These waste products led , in turn , to pollute the air , water and soil. This pollution
endangers the whole environment.
In this paper we studied one of the aspects of waterpollution used in chemical
fertilizers factories and the ways of treatment stations designing and the great
role played by these stations in diminishing the great damage caused to rivers ,
lakes , seas and water –store. This has positively a good effect on environment
and economy in general.
It is necessary to operate the used-water treatment stations and recycling this
water after purifying and refining it within the closed-circuit system effectively
and by using modern computerized techniques concerning design , operation and
investment.
This study is of four chapters and a list of references.
The first chapter includes a short glimpse about the treatment stations and their
main lines concerning design and distribution.
The second chapter is about the sections of the phosphate fertilizers factories and
about the acidic water resulting from these sections.
The third chapter gives a glimpse about the treatment of polluted water in the
phosphate fertilizers factory.
The fourth chapter includes the practical section with some designs and results.
Finally , a list of the arabic and foreign references.
The use of composite materials, and modern technology of plasma
spraying has provided a possibility to obtain a coating with very special
properties. Owing to physics- chimecs changes, changeable valence, low
thermodynamic strength for Ferro-oxide
s the coating, which made from
Ferro oxide composite, has very high specifications investment, and
provides protection for machines which work in difficult circumstances.
Ferro oxide composites behavior, during spraying, studies shows that
changes which took place in these materials are similar to those which
happened during sintering. An influence of plasma generator current
intensity has been studied on microhardness of forming phases, on phases
structure propositions, and on porosity. Microhardness increase when
current intensity was increased, while porosity is decreased.
Wear resistance has also been studied for this post in both, dry and wet
(oily) friction circumstances. Comparable with other materials it has been
found that Ferro oxide materials had a high resistance for wear and a low
friction coefficient.
It is also important that when selecting the spraying materials, to
determine requirements which we need from coating and to analyze its
investment circumstances on specific elements of machines to obtain a
high investment properties coating.
