Unit 24: Applications of Pneumatics and Hydraulics Unit code: J/601/1496 QCF level: 4 Credit value: 15

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1 Unit 24: Applications of Pneumatics and Hydraulics Unit code: J/601/1496 QCF level: 4 Credit value: 15 ASSIGNMENT 3 CIRCUIT DESIGN TARGET SUBMISSION DATE: NAME: I agree to the assessment as contained in this assignment. I confirm that the work submitted is my own work. Date Issued: Signature: Date submitted: This assignment will be used to grade the sections highlighted. L03 Be able to design pneumatic and hydraulic circuits Assessment Criteria for a pass 3.1 design and produce a circuit design diagram for either a pneumatic or hydraulic multi-actuator sequential operation circuit, that includes emergency stop functions 3.2 design and produce a circuit design diagram for either a pneumatic or hydraulic rotary actuation system that includes speed control in both directions 33 design and produce a circuit design diagram for either an electropneumatic or electro-hydraulic system arrangement 3.4 design and produce a circuit design for either a pneumatic or hydraulic fail-safe circuit application Achieved identify and apply strategies to find appropriate solutions. MERIT effective judgments have been made complex problems with more than one variable have been explored an effective approach to study and research has been applied Achieved select/design and apply appropriate methods/ techniques present and communicate the appropriate findings relevant theories and techniques have been applied. a range of methods and techniques have been applied. a range of sources of information has been used. the selection of methods and techniques/sources has been justified the design of methods/techniques has been justified complex information/data has been synthesized and processed appropriate learning methods/techniques have been applied the appropriate structure and approach has been used coherent, logical development of principles/concepts for intended audience a range of methods of presentation have been used and technical language has been accurately used communication has taken place in familiar and unfamiliar contexts the communication is appropriate for familiar and unfamiliar audiences and appropriate media have been used

2 use critical reflection to evaluate own work and justify valid conclusions take responsibility for managing and organising activities demonstrate convergent/lateral/ creative thinking DISTINCTION conclusions have been arrived at through synthesis of ideas and have been justified the validity of results has been evaluated using defined criteria self-criticism of approach has taken place realistic improvements have been proposed against defined characteristics for success autonomy/independence has been demonstrated substantial activities, projects or investigations have been planned, managed and organised activities have been managed the unforeseen has been accommodated the importance of interdependence has been recognised and achieved ideas have been generated and decisions taken self-evaluation has taken place convergent and lateral thinking have been applied problems have been solved innovation and creative thought have been applied receptiveness to new ideas is evident effective thinking has taken place in unfamiliar contexts

3 Feedback Comments: This Assessment brief has been internally verified by...date... Grade Awarded: Tutor Signature Date:... The script has been internally verified by... Date...

4 GENERAL INTRODUCTION TO ASSESSMENT STRATEGY Throughout the module you should do the following. Study relevant course notes. Study the recommended textbooks. Use the standards publications available in the library. Make use of suitable web sites. Make use of journals on fluid power. Make use of manufacturers catalogues. (RS, NORGREN, REXROTH and so on). Make use of the standard information pack from the British Fluid Power Association. In the design parts, you should use the computer software PneuSim Pro. The context help contains diagrams, pictures and symbols. Your assignment should be structured with headings and subheadings. The work must be your own. Copies of pages from the internet or from any other source should only be added as reference material. This should be clearly identified and cross-referenced in your text (e.g. diagram numbers and appendix numbers). You may use computer packages such as word to produce your work and scan in pictures. You may do the work in hand writing and paste in pictures and diagrams. What ever method you use, make sure that the work is identifiable as your own unique style and your research. Students who address all the issues in full are more likely to obtain a merit or distinction but so long as the main points are addressed you should obtain a pass grade. Parts of this assignment may be used as evidence of achievement in the PLC module. IMPORTANT: Consult with your tutor to ensure that you understand the work to be done before you commit yourself to any substantial amount of work. SYSTEMS At the end of this assignment seven fluid power systems are described. You will be allocated or asked to select ONE of them in order to complete this assignment.

5 ASSIGNMENT DETAILS PART 1 CIRCUIT DESIGN You will be allocated one of the seven systems described in the last section. Design a pneumatic or hydraulic system to the specification given. The machine must use electric control systems. Decide whether to use hydraulics or pneumatics. Explain all the points considered in arriving at your answer. BASIC HARDWARE CIRCUIT At this point you should not design the control system, only the basic circuit. You need not consider the materials, style or quality of the hardware at this stage. You should produce your drawing to the ISO standard. All the main control valves must be solenoid operated. Using PneusimPro, design and test the circuit if possible (e.g. using manual overrides on the valves) Explain in detail the strategy used to arrive at your design. PART 2 CONTROL AND OPERATION You should now consider how control of the system is to be produced and automatic operation achieved. Remember that electric control must be used. If you have already studied the PLC module, you may use any of the techniques taught there. List the sequence of operations and use a suitable graphic aid such as a cycle diagram or a step sequence diagram. Consider whether to use a PLC or a hardwired electric circuit. Discuss the benefits and disadvantages of both. Identify sensors that can be used to make the system work automatically in the correct sequence. Modify your circuit drawing by adding the sensors and/or additional valves. Construct a separate circuit diagram (within the same project) showing the electric wiring diagram and produce a control circuit if require. This will be either a grafset or ladder diagram. You may need help and advice on this. Demonstrate the system working by using the simulation feature.

6 PART 3 SAFETY ASPECTS This section concerns the safe design and operation of the machine. Consider the safety legislation that is appropriate to this installation. Identify and discuss the main safety legislation applicable to the installation, commissioning operating and maintaining the machine. Identify the main dangers to look out for when commissioning, operating and maintaining this particular machine. Find out about and explain the reasons for using the following safety features. o Lock out facility. o Automatic cut out. o Emergency stop. o Fail safe. (e.g. safe parking position). o System protection. Identify which you need to incorporate in your design and give your reasons. You should consider things such as : o Prevention of unauthorised tampering. o Possibility of the machine becoming jammed or clogged. o Overheating. o Overpressure. o Fluid levels. o Power overloads Modify your circuit diagram to include appropriate safety features and add suitable text notations if required. This must include an emergency stop PART 4 SPECIFICATION AND COST When costing the system the following should be considered. Explain what each means and list what would be included in each for this machine. o Capital cost. o Running cost. PART 5 COMMISSIONING AND MAINTAINING THE SYSTEM In this section you should consider commissioning and maintenance aspects of the machine. Write a brief report outlining the commissioning procedures to be used. Write a brief report outlining the maintenance procedures to be used.

7 SYSTEM 1 HOOK TWISTING MACHINE A company makes a range of hooks from flat plate for use with climbing gear and safety equipment. The outline shape fits into a rectangle approximately 100 mm by 150 mm. The last part of the manufacturing process is to twist the hook by 90 o. A single machine is to be custom built to do the following. The hooks are manually loaded into a magazine. The hooks are fed one at a time into a clamp with the hook end sticking out. A chuck is advances and grips the hook end. This is then twisted. The clamp releases and the chuck returns pulling the hook out of the clamp and then drops it into a bin below. The cycle repeats.

SYSTEM 2 DRILLING MACHINE The diagram shows an outline design for a proposed machine to be used for drilling a hole in a work piece. First the work piece is put in position.

8 SYSTEM 2 DRILLING MACHINE The diagram shows an outline design for a proposed machine to be used for drilling a hole in a work piece. First the work piece is put in position. Next the guard must be lowered and the work piece clamped by cylinder C. Three seconds after the guard is lowered, the drilling commences automatically. The work piece is fed against the drill by cylinder B and this is a double rod type with the rod fixed at each end. The speed of the feed must be controllable.

SYSTEM 3 TUBE SWAGING MACHINE A tube is placed on the rests. The start is initiated and the two end cylinders acting at a low pressure advance and centre the tube.

9 SYSTEM 3 TUBE SWAGING MACHINE A tube is placed on the rests. The start is initiated and the two end cylinders acting at a low pressure advance and centre the tube. This initiates the clamp cylinders operated at high pressures. When the clamps are in place, the pressure on the end cylinders is increased to force the ends further and swage the tube at both ends. The stop is initiated and this makes the end cylinders retract followed by the release of the clamp cylinders. A rotary actuator then ejects the tube into a box.

10 SYSTEM 4 FURNACE CONVEYOR When the start is initiated, the furnace door is opened and the trolley advances 1.5 m from its normal position. The chuck closes on the object in the furnace and grips it. The trolley moves back 3 m and drops the object into a tank underneath. The door must close as soon as possible to reduce heat loss. The trolley moves forward 1.5 m to its normal position. The trolley might be moved by two cylinders as shown in order to achieve the 3 positions required. The door is operated by a motor and lead screw arrangement. A second start control is to be situated near the furnace for inspection purposes.

11 SYSTEM 4 BAR TRIMMING MACHINE A steel company produces large flat bars of various dimensions ranging from 100 mm x 25 mm to 300 mm x 100 mm. The lengths to be cut are to be done in batches with lengths in any multiple of metres from 1 to 10 m. A single machine is to be custom built to do the following. The bar comes along a roller track and hits an end stop. The bar is clamped tightly. An acetylene cutter head moves to the correct cutting position for the batch. The cutter cuts the length in a controlled manner and retracts. The cut bar must be ejected and the process repeated.

12 SYSTEM 5 PRESS TOOL The press tool is lowered and raised by one complete revolution of the drive shaft. The operator brings down the guard and when at the bottom, the lock cylinder automatically engages. The press cycle automatically starts. First the clutch engages but only if the press tool is in the correct up position. The press tool descends onto the die and then rises automatically. When fully raised, the clutch must be disengaged and the guard lock is disengaged. The lock cylinder must not open unless the press tool is fully raised and stopped at this position. You must select and arrange appropriate sensors as required.02

13 SYSTEM 6 RIVETING MACHINE The machine is based around a pillar drill design. The purpose is to spin rivet two adjacent rivets one at a time. The machine must not operate unless the guard is down and the start switch pressed. The cycle is as follows. Lower guard Start Clamp Lower riveting head. Retract riveting head. Index Lower riveting head. Retract riveting head. Return index to normal position. Unclamp. You must select and arrange appropriate sensors to make the cycle work.

14 SYSTEM7 CONVEYOR SYSTEM Identical boxes are dropped onto the end of a conveyor from a gravity chute and travel along to a junction where they may carry on to processing station A or be diverted to station B. Drive motor C operates the first conveyor. Drive motors A and B operate the conveyors to stations A and B. If the boxes pile up at A because they cannot be removed quickly enough, the divert cylinder is operated automatically and the boxes are sent down a second conveyor to station B. If station A clears, boxes are not diverted. If both stations become clogged at the same time, the stop cylinder is activated to prevent further boxes coming out of the gravity chute and the drive motor C is stopped. If either station clears, this process is reversed. You will need to devise a sensor system to detect a pile up at each station. This will occur when a box comes to rest against the box in front of it at a given point on the conveyor.

Handling station. Ruggeveldlaan Deurne tel

Handling station. Ruggeveldlaan Deurne tel Handling station Introduction and didactic background In the age of knowledge, automation technology is gaining increasing importance as a key division of engineering sciences. As a technical/scientific