Specifying a parts nominal wall thickness is the first step in determining its manufacturability, performance and cost. Dimensioning The recommended general wall thickness of injection molded parts depends on the size of the geometry, the material of choice and the desired performance of the geometry. Here, performance is used to sum up desired characteristics in the following fields: Mechanics — Strength and stiffness. Impact — Ability to absorb mechanical energy.
Flammability — Ease with which a material ignites. Wall thickness and material viscosity. Higher flow translates into the following: Easier mold cavity filling in case of thin sections. Shorter cycle times. Improved surface quality. Part weight — Obviously, the greater the wall thickness, the heavier the part. Cooling time — The greater the wall thickness, the longer it will take for the part to cool down after injection molding.
Part cost — both of the above, plus larger part volume and increased injection molding cycle time results in higher part cost. Dimensional accuracy — Different areas of the part having different cooling rates, which is typically the case when the wall thickness is high or not uniform, leads to molded-in residual stresses that cause the part to warp after being ejected from the mold.
Part performance — Thick sections can cause voids to arise within the wall thickness. Cardiac muscle, like skeletal muscle, is comprised of sarcomeres, the basic, contractile units of muscle. Sarcomeres are composed of long, fibrous proteins that slide past each other when the muscles contract and relax. Two of the important proteins found in sarcomeres are myosin, which forms the thick filament, and actin, which forms the thin filament.
Myosin has a long, fibrous tail and a globular head that binds to actin. The myosin head also binds to ATP, the source of energy for cellular metabolism, and is required for the cardiomyocytes to sustain themselves and function normally. Together, myosin and actin form myofibril filaments, the elongated, contractile threads found in muscle tissue. Cardiac muscle and skeletal muscle both contain the protein myoglobin, which stores oxygen. Cardiac muscle is adapted to be highly resistant to fatigue.
Cardiomyocytes have a large number of mitochondria, enabling continuous aerobic respiration. Cardiac muscle also has a large blood supply relative to its size, which provides a continuous stream of nutrients and oxygen while providing ample removal of metabolic waste. Cardiac Muscle : The tissue structure of cardiac muscle contains sarcomeres that are made of myofibrils with intercalated disks, that contain cardiomyocytes and have many mitocondria. The myocardium has variable levels of thickness within the heart.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'thickness. Send us feedback. See more words from the same century. Accessed 12 Nov.
More Definitions for thickness. See the full definition for thickness in the English Language Learners Dictionary. Nglish: Translation of thickness for Spanish Speakers. Britannica English: Translation of thickness for Arabic Speakers.
Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free! Log in Sign Up. Save Word. Definition of thickness. Synonyms for thickness Synonyms consistence , consistency , density , viscidity , viscosity Visit the Thesaurus for More.
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