SUSTAINABLEESSENTIALSKILLS

Trades WorksheetsBook Three

SKILLPLAN

The content for this publication was developed by SkillPlan as part of a joint project with Buildforce Canada to further the use of Essential Skills concepts by the construction industry in its training activities. This publication is intended to support instructors and apprentices in improving performance and success rates in technical training, and was part of a project that involved industry partners who deliver technical training.

Originally created in 2001 as the Construction Sector Council, BuildForce Canada is a national industry-led organization committed to working with the construction industry to provide information and resources to assist with its management of workforce requirements. The mandate of BuildForce Canada is to provide accurate and timely labour market information (LMI) to advance the needs of the entire construction industry. BuildForce Canada will lead value-added programs and initiatives that build the capacity and the capability of the construction workforce to meet current and future industry demand to drive economic growth in Canada.

SkillPlan is an organization with over twenty years of experience developing workplace materials for the construction industry. Our programs and resources provide industry-specific training and information that address skills gaps and improve worker success prior to and during technical training and employment in the building trades. We work with employers, training schools, technical trainers, apprentices, and journeypersons to improve the Essential Skills of the workforce.

This publication may be reproduced provided that each page used is reproduced in its entirety without modification, and with all legal notices maintained. No part of this material may be reproduced or used for any commercial purpose or sold by any person.

For more information visit

buildforce.ca

For more information visit

SKILLPLAN

skillplan.ca

© 2014

Funded by the Government of Canada’s Adult Learning Literacy and Essential Skills Program (ALLESP).

iTrades Worksheets Book Three

What is the purpose of this collection of Worksheets?These worksheets are part of a project to encourage integrating Essential Skills into technical training. The worksheets address competencies that are outlined in the National Occupational Analysis and are part of every trades training curriculum, regardless of region or level. The content originated in trades training curricula but is enhanced with features that make Reading, Document Use and Numeracy tasks transparent.

The purpose of this collection of worksheets is to• provide ready-made materials for instructors to use • model an Essential Skills approach that integrates Essential Skills strategies into

technical training topics • provide a means to assist apprentices who find technical training difficult

Who should use these Worksheets?Technical instructors can decide which worksheets are appropriate for individual apprentices, study groups and classes. Educators in settings that prepare students for apprenticeship or who have an interest in work-related applications may find some worksheets appropriate.

Why use these Worksheets?Each worksheet activity was suggested and reviewed by an experienced trades instructor. The trades topics are useful for more than one trade. For example, several trades use fan laws; however, this topic is only discussed in one of the workbooks under one trade.

The worksheets provide practice and strategies to reinforce concepts instructors present in class. Instructors can use them with apprentices to review and to teach using a clear process that can become a transferable strategy. The activities have been carefully selected to identify technical training topics that are problematic for apprentices.

Integrating Essential Skills into worksheets helps apprentices develop transferable skills including:

• locating and integrating information from complex text and information displays that use technical terms, abbreviations and symbols

• translating problems into mathematical operations using several steps of calculation and a combination of formulae

introduction

ii

Introduction

SKILLPLAN

hoW can the Worksheets be used? The worksheets are arranged in three workbooks ordered alphabetically by trade. A complete listing of the topics in all three workbooks is on the back inside cover.

Instructors can choose worksheets as they fit into their curriculum or to supplement existing study materials or as a class learning activity. Worksheets can also be used with apprentices who need extra practice.

Instructors can also look beyond the topic and examine the layout and concepts addressed. They can develop their own content using these ideas to integrate the Essential Skills appropriate for their apprentices and trade application.

hoW can instructors participate in this project?These workbooks and accompanying instructor’s guide are part of a project to integrate Essential Skills into technical training. You are invited to join the growing community of technical training instructors who are learning more about Essential Skills and how this approach can facilitate effective trades training and increase success for more apprentices.

Here is how you can participate now and in the future:• Download copies of these workbooks and other related publications at

www.buildforce.ca.• Use these materials with your apprentices• Design your own materials using the same Essential Skills features

The completed project envisions a virtual community of technical training instructors who will post their own worksheets and other materials to share with instructors across Canada. There will be opportunities for networking online, a 1-800 information service, and instructor training courses. The goal of these initiatives is to inspire instructors to add to their credentials by meeting the requirements of a formal Essential Skills endorsement program.

iiiTrades Worksheets Book Three

Introduction

table of contentsRefrigeration and Air Conditioning Mechanics .............................................1

Understanding Fan Laws ...............................................................................................3Using Fan Laws on the Job ............................................................................................9Using the B52-05 Mechanical Refrigeration Code ..........................................................11Determining Pressure Relief Valve Requirements ...........................................................13Determining Discharge Piping Size ...............................................................................16

Sheet Metal Workers ................................................................................25Calculating a Given Elbow Offset ..................................................................................27Using Constants to Calculate the Length of Straight Duct ..............................................31

Wall and Ceiling Installers .........................................................................37Reading Engineered Drawings .....................................................................................39Locating Information in the Wall and Ceiling Standards Manual .......................................45Using a Drawing to Calculate Missing Dimensions .........................................................50Determining Grid Layout .............................................................................................55

Answer Key ..............................................................................................63Understanding Fan Laws .............................................................................................63Using Fan Laws on the Job ..........................................................................................67Using the B52-05 Mechanical Refrigeration Code ..........................................................69Determining Pressure Relief Valve Requirements ...........................................................69Determining Discharge Piping Size ...............................................................................72

Calculating a Given Elbow Offset ..................................................................................72Using Constants to Calculate the Length of Straight Duct ..............................................75

Reading Engineered Drawings .....................................................................................77Locating Information in the Wall and Ceiling Standards Manual .......................................78Using a Drawing to Calculate Missing Dimensions .........................................................78Determining Grid Layout .............................................................................................80

1Trades Worksheets Book Three

Refrigeration Mechanics make, install, repair and service residential, commercial and industrial cooling and heating systems in supermarkets, restaurants, office buildings, manufacturing facilities, hospitals and other structures. They recharge systems with refrigerant gases as required. They also connect rooftop units to gas, test and balance systems and connect electrical systems.

Act iv i t iesThere are five activities in this section. Two activities provide strategies and application of the Fan Laws. Three activities provide practice locating and applying information in the B52-05 Mechanical Refrigeration Code.

• Understanding Fan Laws• Using Fan Laws on the Job• Using the B52-05 Mechanical Refrigeration Code• Determining Pressure Relief Valve Requirements• Determining Discharge Piping Size

Nat ional Occupat ional Analys is (NOA)The NOA has identified the following tasks as being required for a fully competent tradesperson in this trade:

• Interprets tables, charts and diagrams.o Knowledge of types of refrigeration tables, charts and diagramso Knowledge of refrigeration and electrical and gas, acts, codes, legislation,

regulations and specifications• Complies with government acts, codes, standards and regulations.

o Ability to apply standards, codes and regulations• Confirms heating, ventilating and air conditioning requirements.

o Ability to calculate air flow/air quality requirements

refrigreation and air conditioning Mechanics

Refrigeration and Air Conditioning Mechanics

2 SKILLPLAN

Essent ia l Sk i l ls Highl ightsThese activities combines Reading, Document Use and Numeracy at Level 4.

Reading and Document Use

• Locate and integrate multiple pieces of information in complex text and information displays including tables

• Use specialized knowledge such as trade terms and abbreviationsNumeracy

• Make multiple steps of calculation• Translate problem into a set of mathematical operations using several steps of

calculation and a combination of formulae

Refrigeration and Air Conditioning Mechanics

3Trades Worksheets Book Three

understanding fan laWsFan laws are equations stating the relationship between existing fan conditions (old) and desired fan conditions (new). A fan operating in a given system moves a definite volume of air through the system. If, for example, the speed (RPM) of the fan is increased or decreased, the volume (CFM) of air moving through the system changes in proportion. The static pressure (SP) and brake horsepower (BHP) will also change in proportion.

Fan Law #1This is a proportion that compares cubic feet per minute (CFM) to revolutions per minute (RPM). If the CFM increases, the RPM increases proportionately. If the CFM decreases, the RPM decreases.

CFMnewCFMold

= RPMnewRPMold

CFMnewCFMold

= RPMnewRPMold

CFMnew19 750

= 700785

19 750 × 700 785 =

13 825 000 785 = 17 611.5 cfm rounded off to one decimal place

A fan is producing 19 750 cfm at 785 rpm. If the rpm is changed to 700 rpm, how many cfm will be produced?

old cfm

new cfm

old rpm new rpm

exaMple:

Fan Law #2The following two equations are used to calculate the static pressure (SP) a fan will produce after the RPM or CFM is changed. You can use either CFM or RPM to calculate SP. Static pressure varies directly as the square of the RPM or CFM. If the CFM or RPM increases the SP increases.

SPnewSPold

=( CFMnewCFMold )2

SPnewSPold

=( RPMnewRPMold )2

Refrigeration and Air Conditioning Mechanics

4 SKILLPLAN

If you know the SP and need to calculate the CFM or RPM, you need to adjust the formula.

SPnewSPold

= CFMnewCFMold

SPnewSPold

= RPMnewRPMold

SPnewSPold

=( RPMnewRPMold )2

SPnew0.65 =( 575550 )

2

SPnew = (1.045454545)2 × 0.65 = 0.71" sp rounded off to two decimal places.

A fan is producing 0.65" static pressure. The RPM is changed from 550 rpm to 575 rpm. What is the new static pressure?

old sp

new rpm

old rpm

exaMple 1:

SPnewSPold

= RPMnewRPMold

1.851.2

= RPMnew1 120

1.541666667 × 1 120 = RPMnew

1.241638702 × 1 120 = 1 390.6 rpm rounded off to one decimal place.

The static pressure increases from 1.2" to 1.85". The RPM was 1 120. What is the new RPM?

The question asks you to calculate the new RPM so you have to adjust the formula.

old sp

new rpm

old rpmnew sp

exaMple 2:

Refrigeration and Air Conditioning Mechanics

5Trades Worksheets Book Three

Fan Law #3Brake Horsepower (BHP) is the total power applied to the rotating shaft of the fan. BHP depends on:

• the speed of the fan• the load of the fan

The equation means that the fan brake horsepower (BHP) varies as the cube of the fan RPM.

BHPnewBHPold

=( CFMnewCFMold )3

BHPnewBHPold

=( RPMnewRPMold )3

Note: You can use either RPM or CFM to calculate BHP. It works exactly the same.If you know the BHP and need to calculate the CFM or RPM, you need to adjust the formula.

BHPnewBHPold

= CFMnewCFMold

BHPnewBHPold

= RPMnewRPMold

3 3

BHPnewBHPold

=( RPMnewRPMold )3

BHPnew 10 =( 1 150 950 )

3

Note: Use the χ3 button on your calculator. You might have to use 2nd function.

BHPnew = (1.210526316)3 × 10 = 1.773873743 × 10 =17.7 bhp rounded off to one decimal place.

The bhp at 950 rpm is 10 bhp. Calculate the new bhp requirement at 1 150 rpm.

old rpm new rpmnew bhp old bhp exaMple 1:

The BHP at 17 500 cfm was 34. Calculate the new CFM if the BHP is changed to 27.

BHPnewBHPold

= CFMnewCFMold

3

2734

= CFMnew17 500

3

0.794117647 × 17 500 = CFMnew

0.926036878 × 17 500 = 16 205.6 cfm rounded off to one decimal place.Note: You will need to use z on your calculator.

3

exaMple 2: