part5

Robot Application and Specification Preparation

Industrial Robot Applications
Developing a Solution Industrial Robots Application

Welding System

MMA Low-cost
For thick metal
Use Welding Incense

TIG Medium-cost
For thin metal (SS /aluminum)
Use Argon Gas (wire add)

MIG High-cost
For industrial purpose
Automatic Wire / Gas

Robot Welding System – Robotic Welding Guns / welding machine / welding wire / gas mixer / welding controller / gas / computer / Electrical harness / welding torch

Industrial Robot with a Positioner

Arc Welding

A MIG welding robot will have the welding torch mounted at the end of the wrist. For many applications the torch is water cooled.
The wire supply is either a spool mounted on the side of the robot base or, more normally, a bulk pack located outside the robot cell.
The dress package will also feed the inert gas and water to the welding torch.
The welding process is controlled via a welding power source normally positioned close to the robot

Positioner (1) simplest being a head and tail-stock with a servo drive. (2) two axis positioners are able to orientate the part in two axes to provide access to achieve weld positions. (3) built into two station positioners with two head and tailstocks being mounted onto a turntable.
torch service station : automated cleaner consisting of a router to clean the inside of the weld torch shroud and an oil spray to reduce the adhesion of the spatter.

Developing a Solution

achieve the optimal outcome, on-time implementation,
Determining Application Parameters
Initial Concept Design
Controls and Safety
Testing and Simulation
Refining the Concept

Determining Application Parameters

The first step toward the development of a successful project is to obtain a detailed understanding of the current application.
The engineer should obtain all relevant drawings and documentation for the parts to be produced, as well as the basic process details.
The engineer should also discuss the application with the person currently performing the process. Operators are very flexible and generally do solve problems.

The next step is to define the required production rate, number of shifts the equipment is to be used for, number of hours per shift, and number of working weeks per year.

Calculate Target cycle time
Target cycle time =total time available/required output * efficiency factor

Example

Target cycle time
=total time available/required output * efficiency factor

Initial Concept Design

The initial concept design often results from previous experience as much as it does from a detailed study of the application.
the engineer may be able to suggest an outline concept as a possible solution.
Some Guidance ….
Arc Welding, Machine Tool Tending, Palletising, Packing, Assembly, Other Applications

Controls and Safety

The approach for safety is very dependent on the legislation and factory-specific requirements.
The main requirement for safety is that any operators, maintenance personnel, or other personnel in the factory cannot be placed in danger.

Testing and Simulation

Refining The Concept

There are typically a number of iterations of the initial concept to ensure the final concept provides a workable and cost-effective automation solution for the specific application.
It is better to ensure each robot is fully utilized.

Specification Preparation

Functional Elements of a Specification
Scope of Supply
Buy-Off Criteria
Covering Letter

Request for Quotation Letter
User Requirements Specification

OVERVIEW

The customer is a leading subcontract engineering customer with X manufacturing sites in the UK.
The customer manufactures a wide range of fabrications, in steel and aluminium, for OEMs….
The customer has ….CNC machinery for the initial preparation of parts, including laser cutting and bending, and therefore manufactures parts to a high standard and tight tolerances.
All welding operations, the majority of which utilize the MIG welding process, are carried out manually. The intention is to invest in appropriate automated welding equipment to improve the productivity of the welding operations and the quality of the parts being produced.

The customer has a diverse range of MIG welding equipment, including sys tems from both Esab and Kemppi (generally 300–350 amp).
The fixtures have been manufactured in-house and provide simple location of the parts with manually operated clamps included as necessary.
The input parts are prepared in a separate facility, which includes the cutting and bending operations, close to the welding area.
The parts are prepared in batches that can vary from 20 to 100 units. These are loaded into various bins and carriers, dependent on the type of part, and transported to the welding area.

Each welding station is separated by welding screens and generally comprises a table on which is mounted the relevant welding fixtures for the part to be processed.
Welding fixtures are stored adjacent to the welding area. Each welding station is equipped with one set of MIG welding equipment and is normally occupied by one welder. In total there are 20 welding stations.
The welding facility operates two shifts, 5 days per week, with 8 hours per shift. There are 20 welders employed on days and 10 welders employed on the night shift. The parts for the assemblies to be produced are delivered to the welding station. Each welder will take parts as appropriate, locate them in the fixture, and perform the necessary welding operations.

Automation Concept

The customer intends to introduce a number of robot welding systems over time to automate the majority of the welding operations.
This specification provides details of all the parts currently being produced (see Section A.2).
The vendor is therefore requested to consider which parts should be addressed by the first system to be introduced to ensure this first system achieves the objectives for the project, is fully utilized, and provides a sound introduction for robot welding.
The customer envisages an automation system concept that allows the operator to load individual parts into a fixture(s) at one work station, whilst the robot performs welding operations at a separate station.
On completion of both operations, the robot and operator will then switch stations to allow the robot to continue welding whilst the operator unloads the welded part and loads new parts to be welded. It will be necessary to balance the welding time and the load/unload time to ensure the utilization of the robot is maximized as well as ensuring the operator is utilized effectively.

The proposed solution must include the ability to change fixtures quickly and with repeatability to ensure changeover between different assemblies is accomplished with the minimum of downtime. The concept must also provide easy access for the delivery of parts and the removal of completed assemblies.

A.2 REQUIREMENTS

•A.2.1 Products

•A.2.2Tolerances and Quality / •The system will be required to achieve the above quality standard with a yield of 99.5%.

A.2.3 Fixtures
The vendors should include the most appropriate clamping techniques and fixture coding to provide for automatic selection of the appropriate robot programme based on the fixture(s) located within the cell.
A.2.4 Cycle Time and Availability
The vendor must provide cycle time estimates at 100% efficiency for the parts they have selected to be produced by the robot cell.
In addition, production outputs should be determined based on the batch sizes and overall volumes identified in Section A.2.1. The target availability for the system is 85%. The production output calculations should include 15% down time due to maintenance, fixture changeovers, and so on.

A.2.5 Welding Equipment
The customer will accept recommendations from vendors in relation to the most appropriate welding equipment for the robot cell. A complete welding package must be offered, including torch mounting, torch cleaning, antispatter spray, and wire cutting. Additionally, recommen dations on wire delivery, reel or bulk pack, would be welcomed.

A.2.6 Controls and HMI
provide all the functionality to operate and maintain the system, as well as to recover from faults. The minimum functions
• Assembly/program selection / • System start • System stop • Emergency stop • Fault location indication
The control system will also provide production management information
• Number and type of assemblies produced per shift • Cycle time • OEE …..
include log, cause of the stoppage until the fault is cleared.
• Weld equipment fault • Robot fault • Stoppage due to lack of product • Stoppage for cleaning/preventative maintenance.

A.2.7 Enclosure
The enclosure will be constructed from steel panels with appropriate viewing panels. It must ensure no access is available to the automated equipment during operation. Simple and safe access, using appropriate interlocks, must be provided to all areas of the system to clear problems in the event of a fault.
The enclosure will provide protection from the welding arc to both the operator and other personnel in the vicinity of the cell.
The cell must operate at a noise level below 80 dB at 1 m when in automated continuous operation. If the process is generating noise above this limit, the enclosure must include suitable sound suppression to reach the desired limit.
The enclosure will include a fume hood over the welding area, with appropriate lighting. The fume hood will include a suitable port to allow the customer to connect to ducting to remove weld fumes from the cell.

A.3 SCOPE OF SUPPLY

A.3.2 SafetyA.3.3 Services
415 V, three phase • 24 V dc • air, 70 psi
A.3.7 Pre-delivery Tests
A.3.8 Delivery
A.3.11 Final Testing and Buy-off
A.3.12 SAT Procedure

A.3.7 Pre-delivery Tests

Factory Acceptance Tests (FAT)
Cycle time for each assembly produced (CT1, CT2, CT3, CT4, CT5)
The length and cause of any down time (DT)
The time required to perform the fixture changeover (FCT)

•Cycle Time and Availability Calculations

2021

Group Assignment on 10 Sep 2021 / 3 Person per Group
– Discuss a industrial robot with automation application that your group are interesting in.
– Discuss information about that robot
– Discuss that automation components.
– Discuss that operation.
(3-5 mins / person)

Robotic Welding Guns & Torches

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3 Person / Group Project….. by 24 Sep 2021

Project VDO Score (10 Point)
… Present information of an Industrial Robot, Find Specification (3 Score)
… Present How to operate Industrial Robot. (3 Score)
… Design your Automation System for specific application, and Present…. (4 Score)

Sent Before Mid-Term Exam…

First-Part Class Attention Score (5 Point)

Mid-Term Exam Score (20 Point)

ETC…

Robotics Exploration (2019)

First Chapter (1/3) refer to Books.

Implementation of Robot Systems
An Introduction to Robotics, Automation, and Successful Systems Integration in Manufacturing / Book • 2015

https://www.sciencedirect.com/book/9780124047334/implementation-of-robot-systems

Class 1

Class 2 Practice makes perfect.

Refer to https://gulfthai.com/?page_id=1375

Class 3