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Register a new userEstimate The Static Fatigue Age For Springs Depending On Accelerated Tests
تقدير عمر التعب الستاتيكي للنوابض بالاعتماد على الاختبارات المسرعة
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Added by
Tishreen University ورقة بحثية
Publication date
2018
fields
Mechanical Power Engineering
and research's language is
العربية
Created by
Shamra Editor
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تم في هذه الورقة البحثية تقديم طريقة جديدة و فعالة لتقدير عمر التعب الستاتيكي للنوابض و ذلك عند عملها بتأثير إما حمل ثابت أو تعرضها لانفعال أو ضغط ثابتين لفترات زمنية كبيرة و ذلك عند درجات حرارة عمل مختلفة، لما لهذا الموضوع من أهمية بالغة، حيث أن النوابض تعتبر مدخرات للقوة من خلال إحداث انفعال فيها ( شدها أو ضغط ) و يجب أن تحافظ على حد أدنى من قيمة هذه القوة. تم في البداية تقديم دراسة نظرية للظواهر المعنية بالأحمال الثابتة لفترات زمنية طويلة و درجات حرارة مختلفة (الزحف – التراخي) و كيفية تسريع الاختبار للحصول على النتائج، و من ثم اقتراح طريقة لتسريع الحصول على الزمن الذي يصل فيه النابض و هو تحت الانفعال إلى القوة الحرجة الدنيا المخزنة ضمنه عند درجة حرارة العمل، تعتمد هذه الطريقة على إجراء اختبارات على عينات ضمن الأفران عند درجات حرارة مختلفة و أعلى من درجات حرارة الاستثمار و التخزين للنوابض و من ثم استخدام النتائج في تقدير عمر التعب الستاتيكي للنوابض عند درجات حرارة التخزين أو العمل الحقيقي.
In this article we present a new and effective method to Estimate the static fatigue age for springs, when it works by static load or static strain for a long time at deferent temperature, this case is very important because the spring is a battery for force and it must save allow value of the force. At the first we present a theory study for “creep and relaxation “and how we can accelerate the test to get the results, then we suggest method to accelerate the test to know when the spring retch to the minimum allowable value of the force at work temperature degree, this method depend on tests at samples at deferent temperature degrees, higher than work and storage temperature, and then use the results to estimate the static fatigue age for springs at real storage and work temperature.
References used
MANARDI, F. SPADA , G. "Creep relaxation and viscosity properties for basic fractional models in phenology". The European physical journal . Vol 139,2011, 133-160
TAHERI , F . LIU,Y ."A new experimental testing method for investigation of creepdominant creep-fatigue interaction in alloy 617 at 950co".international journal of pressuer vessels and piping. Vol 154, 2017,75-82
POIRIER,J.P."Creep of crystals high-tempreture deformation processes in metalls , ceramics and minerais" . 2nd. ed. cambredge university press. Newyork , 2005,950
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