Full exam for Advanced Manufacturing Processes in the Mechanical Engineering degree programme at Politecnico di Milano. The document covers: Course of ADVANCED MANUFACTURING PROCESSES Proff. Michele Monno – Barbara Previtali – Matteo Strano SURNAME NAME PERSONAL ID Exam - January 24th 2019 Exercise n. 2 – technological problem To cut a large concrete block on a construction site, it is thought to use an ASJ (Abrasive
Full exam for Advanced Manufacturing Processes in the Mechanical Engineering degree programme at Politecnico di Milano. The document covers: Course of ADVANCED MANUFACTURING PROCESSES Proff. Michele Monno – Barbara Previtali – Matteo Strano SURNAME NAME PERSONAL ID Exam - January 24th 2019 Exercise n. 2 – technological problem To cut a large concrete block on a construction site, it is thought to use an ASJ (Abrasive
Import quality: text was extracted directly from the original document.
Representative passages recognised in different parts of the material. The full extracted text remains available to search, while this compact preview makes the page easier to read.
Course of ADVANCED MANUFACTURING PROCESSES Proff. Michele Monno – Barbara Previtali – Matteo Strano SURNAME NAME PERSONAL ID Exam - January 24th 2019 Exercise n. 2 – technological problem To cut a large concrete block on a construction site, it is thought to use an ASJ (Abrasive Suspension Jet) cutting system. The ASJ system can be equipped with a single Discharge Vessel (DV), with no internal separator between water and abrasive, or with 2 or more vessels, each with 200 liters capacity, equipped with internal separation piston and valves for shifting from one tank to another After some tests using a 100 MPa HP pump that allows water flow up to 200 liters/min, it is estimated that the hydro-abrasive jet should have an exit diameter of 3 mm (with an discharge coefficient Cd = 0,9); the duration of the cut, without interruptions for the refill of water/abrasive, should be no more than 30 min, with an initial abrasive concentration in the DV of 50% and a final equal to 15%. During the rectilinear cutting, the head will remain in a fixed position and the concrete block will be moved thanks to a special electrically powered carrier. Under the indicated conditions, determine for the case of single vessel (with by-pass): 1. The minimum volume of the vessel (VDV) compatible with the assigned parameters. 𝑸𝑫𝑽 [l/min] 𝑽𝑫𝑽,𝒎𝒊𝒏 [l] 2. The initial concentration of abrasive in the vessel, if this has double the minimum volume. 𝑽𝑫𝑽 [l] 3. Assuming a linear variation of the concentration, calculate the amount of abrasive necessary for the cutting (abrasive specific weight = 2 kg /liter) Abr [kg] Furthermore, for the case of Indirect Pumping, determine: 4. Amount of abrasive necessary to complete the cut. Abr [kg] 5. Optimal number of tanks to be used taking into account that the…
First page of the document.
