ME312 Hydraulic System Design Assignment Design Brief

ME312 Design Brief

A hydraulic system is to be designed to conduct several stages of a manufacturing process, namely:

• Stage I: Move a component from location A to location B along a rotating conveyer belt, ensuring adequate control of the speed of the conveyor belt.
• Stage II: When the component arrives at position B, the component will roll onto a table. The table will then be lifted a distance at a set speed once the hydraulic motor has come to a complete stop. The design should ensure that the table does not tilt, even if the component is located to one side of the lift table.
• Stage III: Once the component reaches the maximum extension of the lift table, two actuators are then utilised to apply different forces to the component, as detailed in the individual specifications. These loads must be applied for a fixed amount of time.
• Stage IV: Once the time has been exceeded, the lift is finally lowered to its original position, and the component is manually removed by an employee, with the system operating in a low-pressure setting.

The system must include high-pressure and low-pressure operation modes.

The lowpressure operation mode is a standard configuration for all system parameters (i.e. this part of the system just needs to be included in the circuit diagram but assume a system pressure requirement of 60 psi and maximum flow-rate of 7.0 l∙min-1 for the low pressure pump).

The hydraulic system is to be operated using two electric motors (high-pressure and low-pressure system) connected to the grid via a 3-phase transformer, with both the electric motors and 3-phase transformer to be specified as part of the design (i.e. selection of a 3-phase transformer using the standard sizes supplied by ESB Networks and the electric motors must be selected from Baldor only). A library of key components is presented in Appendix A. For components not listed in this Appendix (e.g. the low-pressure pump, flow dividers or pressure control valves other than pressure relief valves) which may be required to support your design, these components can be added in as generic components in the system and given a clear part number in your Parts List. However, for components listed, you must use these components to design your system and adjust system pressure or flowrate in the system as necessary to meet the design requirements and critical values such as cracking pressures must be clearly specified for each of these additional components in your design report.

The following system specific parameters are based on your student ID.

Your student ID is of the form:

ME312 Report

The report should include the following sections:

• Design Brief
• Design Specification
• Circuit Diagrams
• Parts List
• Overview and Justification of Part Selection Design Brief: Overview of the problem as presented.

Design Specification: Based on the brief provided, the key design requirements and constraints should be identified and listed (bullet points will suffice).

Circuit Diagram: A full circuit diagram of the hydraulic system should be provided using standard hydraulic symbols. Part numbers should be included as well as clear definition of the working lines.

Parts List: The parts list should refer to the part identification number in the circuit diagram and to the part number as per the manufacturer’s description (e.g. as per the part name on the list of attached components). The electric motor should be specified from Baldor (www.baldor.com).

Overview and Justification of Part Selection: The selection of each component should be described and justified (including any theory required in the selection process). For example: “A pump isolation check valve inserted downstream of the hydraulic pump to …. . The cracking pressure of this check valve is set at … bar.”

“The torque required at the outlet of the electric motor is:

𝑇 = √3𝑉𝐼𝜂motor cos 𝛼 𝜔
(1)
where 𝑉 is voltage, … .”
Note the layout of the equations needs to follow standard engineering convention.

ME312 Marking Scheme

The breakdown of marks for this assignment are:

• Design Brief (5 Marks)
• Design Specification (10 Marks)
• Circuit Diagram (30 Marks)
• Parts List (10 Marks)
• Overview and Justification of Part Selection (30 Marks)
• Report Structure (15 Marks)

ME312 Appendix A: List of Available Components