NZQA Expiring unit standard
21171 version 3
Page 1 of 6
Title
Demonstrate knowledge of zinc coating and galvanize and quench
metal components at a hot dip galvanizing facility
Level
3
Credits
11
Purpose
People credited with this unit standard are able to: demonstrate
knowledge of the zinc coating process; identify, evaluate,
control, and monitor health and safety hazards of hot dip
galvanizing and quenching operations; apply zinc coating to
metal components using the hot dip galvanizing process at a
hot dip galvanizing facility; describe the quenching process;
and quench metal components at a hot dip galvanizing facility.
Classification
Hot Dip Galvanizing > Hot Dip Galvanizing Operations
Available grade
Achieved
Entry information
Critical health and
safety prerequisites
Prerequisites: Unit 3800, Operate a radio remote or pendant
controlled overhead crane and lift and place regular loads; Unit
25130, Describe hazards, safety and emergency procedures,
and exhibit safe working practices at a hot dip galvanizing
facility; and Unit 25133, Demonstrate knowledge of venting and
draining for hot dip galvanizing; or demonstrate equivalent
knowledge and skills.
This unit standard is
Explanatory notes
expiring
1
The current version of the following documents must be complied with:
Health and Safety in Employment Act 1992;
Health and Safety in Employment Regulations 1995;
AS/NZS 4680:2006 Hot-dip galvanized (zinc) coatings on fabricated ferrous articles,
available at http://www.standards.co.nz.
After-Fabrication Hot Dip Galvanizing: A practical reference for designers, specifiers,
engineers, consultants, manufacturers, and users, Galvanizing Association of
New Zealand, telephone 09 589 5400, fax 09 579 8907, website
http://www.galvanizing.org.nz.
2
It is recommended that assessment against this unit standard follows or is concurrent
with assessment against Unit 21168, Demonstrate knowledge of and pickle metal
components at a hot dip galvanizing facility; Unit 21169, Demonstrate knowledge of
and rinse metal components at a hot dip galvanizing facility; and Unit 21170,
NZ Motor Industry Training Organisation
(Incorporated) (MITO)
SSB Code 101542
 New Zealand Qualifications Authority 2016
NZQA Expiring unit standard
21171 version 3
Page 2 of 6
Demonstrate knowledge of the fluxing process and flux metal components at a
galvanizing facility.
3
Definitions
Company procedures refer to all documented policies and procedures of the
candidate’s employer at the time of training including, but not limited to, those relating
to health, safety, environment, quality, and operations.
Immersion refers to dipping a component in molten zinc until the temperature of the
inner core of the component matches that of the molten zinc.
Double-end dipping refers to galvanizing articles that are longer than the bath by
dipping one end of the component at a time.
Surging refers to the motion of a component within the solution causing a wave.
Outcomes and evidence requirements
Outcome 1
Demonstrate knowledge of the zinc coating process.
Evidence requirements
1.1
Purpose of hot dip galvanizing is described in terms of After-Fabrication Hot Dip
Galvanizing.
1.2
The materials used at a specific hot dip galvanizing facility are described in
terms of the zinc coating process.
Range
must include – zinc, aluminium;
may include – lead, nickel.
1.3
Working temperature range is identified and described in terms of AfterFabrication Hot Dip Galvanizing.
1.4
Immersion times are described in terms of After-Fabrication Hot Dip
Galvanizing.
1.5
This unit standard is
expiring
The process of checking fabricated components before hot dip galvanizing is
described in terms of venting and drainage requirements.
Range
includes but is not limited to – sealed hollow sections, overlapping
sealed sections, welded plates, internally vented.
1.6
Production of fumes, ash, and dross are described in terms of their causes.
1.7
The means for control of fumes and ash production are described in terms their
function and company procedures.
Range
cleanliness, component temperature, composition, immersion
speed, flux composition.
NZ Motor Industry Training Organisation
(Incorporated) (MITO)
SSB Code 101542
 New Zealand Qualifications Authority 2016
NZQA Expiring unit standard
21171 version 3
Page 3 of 6
1.8
Dross levels are described in terms of contamination of coating and their impact
on available depth.
1.9
Immersion and withdrawal rates and angles are described in terms of company
procedures.
1.10
Tools used for hot dip galvanizing are identified and their functions are
described in terms of company procedures.
Outcome 2
Identify, evaluate, control, and monitor health and safety hazards and environmental
aspects of hot dip galvanizing and quenching operations.
Evidence requirements
2.1
Health and safety hazards are identified and evaluated in terms of legislative
requirements and company procedures.
Range
hazards include but are not limited to – lead, chromate, noise,
burns, heat, splashes, dehydration, emissions, hazardous
materials, obstructions, people in the vicinity, personal injury,
stress, spills, heavy lifting, transferring components between kettle
and bath, steam, hot components.
2.2
The procedures for monitoring and controlling health and safety hazards are
described in terms of legislative requirements.
2.3
Health and safety hazards are controlled and monitored in accordance with
legislative requirements and company procedures.
hazards include but are not limited to – lead, chromate, noise,
burns, heat, splashes, dehydration, emissions, hazardous
materials, obstructions, people in the vicinity, personal injury,
stress, spills, heavy lifting, transferring components between kettle
and bath, steam, hot components.
This unit standard is
expiring
Range
2.4
Environmental aspects resulting from hot dip galvanizing and quenching are
controlled and monitored in accordance with legislative requirements and
company procedures.
2.5
Methods of avoiding dehydration are described in terms of work factors to be
considered and ways of controlling their effect.
Range
2.5
factors – humid atmosphere, clothing, equipment, physical
exertion;
controls – type of fluid, timing of fluid intake (before physical
activity, during physical activity, after physical activity), personal
protective equipment.
The observable symptoms of dehydration are identified and described.
NZ Motor Industry Training Organisation
(Incorporated) (MITO)
SSB Code 101542
 New Zealand Qualifications Authority 2016
NZQA Expiring unit standard
Range
2.6
21171 version 3
Page 4 of 6
evidence is required for at least three symptoms.
Rehydration is described in terms of frequency of intake and effect of
substances on fluid replacement.
Range
substances – water, fruit juice, soft drinks, sport drinks, salt,
alcohol, caffeine.
Outcome 3
Apply zinc coating to metal components using the hot dip galvanizing process at a hot dip
galvanizing facility.
Range
evidence is required of galvanizing solid, plate, hollow, and fabricated
components;
at least one component is to be double-end dipped.
Evidence requirements
3.1
Kettle surface is swept in accordance with company procedures.
Range
prior to immersion, prior to withdrawal, during withdrawal.
3.2
Components are lifted and moved to the hot dip galvanizing kettle in
accordance with company procedures.
3.3
Components are immersed in the hot dip galvanizing kettle in accordance with
company procedures.
3.4
Components are withdrawn from the hot dip galvanizing kettle and visually
inspected for quality of coating in accordance with company procedures.
continuity of coating, uniformity of coating, dross and/or ash
This
unit standard is
contamination.
Component is prepared for
the second dip in accordance with company
expiring
procedures.
Range
3.5
Range
preparation may include – quench, acid.
3.6
Double-end dipping achieves continuous coating with minimal overlap.
3.7
Dags are removed in accordance with company procedures.
3.8
Hot dip galvanizing faults are remedied in accordance with company
procedures.
3.9
Components are completely drained before transferring to the next process in
accordance with company procedures.
NZ Motor Industry Training Organisation
(Incorporated) (MITO)
SSB Code 101542
 New Zealand Qualifications Authority 2016
NZQA Expiring unit standard
21171 version 3
Page 5 of 6
Outcome 4
Describe the quenching process.
Evidence requirements
4.1
Purpose of quenching is described in accordance with company procedures.
4.2
Safety hazards related to quenching are identified and evaluated, in terms of
legislative requirements and company procedures.
Range
includes but is not limited to – splashing, explosion, lifting,
transferring components between kettle and quench tank, steam,
hot components, surging.
4.3
The procedures for monitoring and controlling health and safety hazards related
to quenching are described in terms of legislative requirements.
4.4
Reasons for not quenching components are described in terms of customer
requirements and component type.
Range
reasons include but are not limited to – painting, powder coating,
distortion, intended use.
Outcome 5
Quench metal components at a hot dip galvanizing facility.
Evidence requirements
5.1
Unquenched work is identified in accordance with company procedures.
5.2
Components are quenched in accordance with company procedures.
This unit standard is
Range
solid, hollow, fabricated, double-end dipped components.
expiring
Replacement information
This unit standard has been replaced by unit standard
28441.
This unit standard is expiring. Assessment against the standard must take place by
the last date for assessment set out below.
NZ Motor Industry Training Organisation
(Incorporated) (MITO)
SSB Code 101542
 New Zealand Qualifications Authority 2016
NZQA Expiring unit standard
21171 version 3
Page 6 of 6
Status information and last date for assessment for superseded versions
Process
Version Date
Last Date for Assessment
Registration
1
21 October 2004
31 December 2016
Review
2
23 January 2009
31 December 2016
Review
3
16 April 2015
31 December 2016
Consent and Moderation Requirements (CMR) reference
0114
This CMR can be accessed at http://www.nzqa.govt.nz/framework/search/index.do.
Please note
Providers must be granted consent to assess against standards (accredited) by NZQA,
before they can report credits from assessment against unit standards or deliver courses
of study leading to that assessment.
Industry Training Organisations must be granted consent to assess against standards by
NZQA before they can register credits from assessment against unit standards.
Providers and Industry Training Organisations, which have been granted consent and
which are assessing against unit standards must engage with the moderation system that
applies to those standards.
Requirements for consent to assess and an outline of the moderation system that applies
to this standard are outlined in the Consent and Moderation Requirements (CMR). The
CMR also includes useful information about special requirements for organisations wishing
to develop education and training programmes, such as minimum qualifications for tutors
and assessors, and special resource requirements.
This unit standard is
expiring
NZ Motor Industry Training Organisation
(Incorporated) (MITO)
SSB Code 101542
 New Zealand Qualifications Authority 2016