Thermal Spray Domains and Tasks
This outline demonstrates the areas in which a certified thermal spray
operator is expected to knowledgeable. Note that there appears to be
repetition because sometimes like tasks are performed at different times. For
example, you may see similar items regarding PPE in several domains
because PPE is used at different points in the thermal spray process.
Similarly, masking may be used both prior to thermal spraying and during
thermal spraying.
1. Safety and Environmental Compliance (20% of
examination)
1.1
1.2
1.3
1.4
Perform job safety assessment
1.1.1 Observe & identify obvious hazards
Note hazardous areas such as areas around robots, lathes, gas
supplies and determine emergency shutoffs or controls.
1.1.2 Verify absence or presence of leaks (gas, oxygen), confined
spaces, hotwork, solvents, chemicals, other personnel
Perform more detailed assessment of hazards posed by equipment,
materials, energy sources, spatial area, personnel and other
sources of hazard.
Select appropriate personal protection equipment (PPE),
1.2.1 Identify hazards present
Rate hazards present in work space for particular job being
performed. Know what regulations (federal, state, local) apply.
1.2.2 Distinguish/.differentiate UV, hearing, sight, skin, eyes,
electrical, lockout, robots, respiratory protection
Select proper PPE according to its capability and capacity to
protect the wearer from harm.
Assemble, safely operate & closedown equipment
1.3.1 Set up equipment properly
Ensure gas flows are adequate and equipment configuration
matches job requirements…
1.3.2 Operate equipment safely and correctly
Use equipment according to manufacturer’s suggestions and in
accordance with work instruction
1.3.3 Close down or shut down equipment safely and correctly,
Close or shut down equipment in proper sequence according to
manufacturer’s suggestions and work safety concerns. .
Safely conduct oneself during spraying
1.4.1 Assess spray booth and surroundings
Check spray booth ventilation, exhaust, and make up air systems
are working correctly as well as for electrical hazards and any gas
leaks.
1.4.2
1.5
1.6
Identify safe work zones, (manipulators including robots
and torches).
Verify that the work zone envelop is free of tripping hazards and
that cables will not be caught on surrounding equipment and all
robots, manipulators and torches will not contact work piece or
other equipment
1.4.3 Recognize the symptoms of common workplace hazards
such as burns and heat exhaustion
Ensure that all personal protective equipment is in place and
functional; that clothing will provide protection from UV burns.
1.4.4 Summon supervisor or medical assistance in a timely
fashion.
In the event of injury notify supervisor and seek medical assistance
as quickly as possible.
Confirm correct operation of environmental systems
1.5.1 Distinguish between various environmental systems (dust
collectors, etc.)
Ensure that all environmental systems – dust collectors, make up
air and breathing air systems are operational and functioning
correctly.
1.5.2 Operate environmental systems in compliance with
workplace standards
Operate all environmental systems in accordance with
manufacture’s specifications with proper safety guards and
devices in place.
Mitigate unsafe conditions
1.6.1 Inform supervisor of hazards
When any hazards are identified notify supervision and
management of them for your and other personnel’s protection.
1.6.2 Take action according to safety procedures
Operate equipment and work in accordance with established safety
procedures and practices
1.6.3 Stop work until condition mitigated.
Once unsafe condition is recognized; stop work, notify supervisor
until hazard or unsafe condition is corrected.
1.6.4 Keep workspace clean
Ensure work area is kept clean – the first rule of safe work
environment.
1.6.5 Avoid generating dust clouds of combustible materials.
Set up work in cell so as to maximize effectiveness of dust
collection system and minimize creation of excessive dusts,
especially combustible materials.
1.6.6 Maintain hazardous waste containers closed unless adding
or removing waste
Check to be sure that hazardous waste containers are kept closed
when not being serviced.
1.6.7
Clean up and contain any spills, leaks or overflow of
hazardous materials
Ensure that work area is kept clean and any spills, leaks or
hazardous materials are properly handled. Follow company safe
practices and comply with all regulations governing hazardous
waste disposal.
1.6.8 Comply with all safety policies, practices and procedures
reporting all unsafe activities to Management and/or
Human Resources.
Maintain familiarity with all company safety policies, practices
and procedures. Comply with these as well as any governmental
ones as well. Notify and report all unsafe activities and conditions
to Management and personnel administrators.
2 Set-up and Part Preparation (20% of examination)
2.1
Review documents related to thermal spray job
2.1.1 Determine geometrical aspects
Review drawings, routers, and instructions and compare them with
the dimensional values of the part to be processed
2.1.2 Read and interpret drawings.
Compare and evaluate drawings with part and instructions in
routers. Seek clarification of any discrepancies or questions with
supervision.
2.1.3 Employ commonly accepted thermal spray terminology
Review and confirm terminology and descriptive terms used with
supervision. Seek clarification of any questionable terms or
definitions with supervision
2.1.4 Convert units of measurement.
Verify that all units of measurement are accurate, especially when
any conversions are made.
2.1.5 Review the customer specifications to determine which
areas are to be sprayed.
Review all documentation and compare with physical part to be
processed. When discrepancies are found notify supervision before
proceeding.
2.2
Pretreat substrate for cleaning process
2.2.1 Grit blast in accordance with established work instructions
or other specifications.
Prepare part in accordance with company work instructions and
specifications; confirming that proper grit, pressure and profile is
achieved.
2.2.2 Maintain grit cleanliness and change out
Check grit for proper size and cleanliness. Change grit as needed
and required by specifications and work instructions.
2.2.3 Inspect grit for dust
Verify that grit media is free of excessive dust and fines.
2.3
2.2.4 Check proper pressure settings
Verify that specified pressure settings are maintained and that
nozzle orifice is correct size and not worn beyond specifications.
2.2.5 Spray with compressed air to ensure no grit remains
Following abrasive blasting, remove any dust or residual grit
entrapment with clean compressed air.
2.2.6 Maintain visual inspection for adequate masking
Verify that masking is properly placed and that it is not damaged
during blasting.
2.2.7 Stop blasting and remask as needed
When masking has been damaged during processing, remask part
as needed to protect designated non coated areas.
2.2.8 Contact superior in case of overspray
In the event of over blasting, immediately notify supervision of
error and discrepant part.
2.2.9 Protect the grit blasted surface from contamination
Following blasting and cleaning, protect part in accordance with
established practices and work instructions to avoid contamination
before spray processing.
2.2.10 Maintain the allowable time between grit blasting and
thermal spraying.
Verify that the time between surface preparation by blasting and
spraying does not exceed specifications and work instruction
requirements.
Clean part prior to thermal spraying
2.3.1 Degrease (e.g. Manual wipe down, dip, solvent vapor,
abrasive, detergent, steam washing) according to
established work instructions or as specified
Ensure that parts to be processed are clean, free from oil, grease,
dirt or other contaminants and have been properly cleaned in
accordance with customer specifications and company procedures.
2.3.2 Observe safety standards for solvent and cleaning products
as appropriate.
Perform detailed assessment of hazards posed by equipment,
materials, energy sources, spatial area, personnel and other
sources of hazard
2.3.3 Select solvents that are compatible with metal parts (e.g.,
no methanol on titanium)
Rate hazards present in work space for particular job being
performed. Know what regulations (federal, state, local) apply.
2.3.4 Visually inspect for burrs or imperfections
Check parts for burrs or dimensional discrepancies vs. drawings
and customer specifications. Notify supervision of deviations.
2.3.5 Bake out/preheat to maximum temperature recommended
In the event of oil or grease contamination, bake part to remove
contaminants per work instructions and routing specifications
2.3.6
2.4
2.5
Remove heavy rust or mill scaling using abrasive media to
clean
Verify that all mill scale and rust is removed from parts before
proceeding with coating processing.
2.3.7 Properly handle so as not to recontaminate surfaces
After parts have been processed for surface preparation, verify
that they are free from contamination before processing for
coating.
2.3.8 Remove masking material after cleaning
Verify that all masking materials for blasting have been removed
prior to coating and that all masking materials for coating are in
proper position.
2.3.9 Ensure time between cleaning and degreasing does not
exceed recommended limits.
Ensure that the time between blasting and coating has not
exceeded customer or other specification requirements.
Mask specimen for cleaning prior to grit blasting
2.4.1 Determine the masking requirements, if any
Review part masking plans with part drawings and router
requirements and work instructions prior to processing.
2.4.2 Select proper masking material for the application (vinyl
take or rubberized material)
Ensure that the proper masking materials have been selected and
used before processing for abrasive blasting.
2.4.3 Inspect to ensure mask is properly placed
Verify that masking has been properly positioned prior to abrasive
blasting operations.
2.4.4 Clean pre and post masking as appropriate.
Ensure that all masking has been removed from part following
abrasive and coating operations in accordance with routing work
instructions.
Measure suitability of surface for coating
2.5.1 Measure the effects of cleaning using angular profile
Verify that component surfaces meet profile and cleanliness
requirements prior to commencing spray operations.
2.5.2 Ensure time between blasting and spraying does not exceed
recommended limits.
Verify that the component to be coated has not exceeded the
specified time between surface preparation and coating
operations.
2.5.3 Identify characteristics of acceptable spray surface
Ensure that component surface meets that specification and router
requirements for texture and cleanliness prior to processing for
coating operations.
2.5.4 Use Profilometer or comparator to measure roughness
2.6
2.7
Confirm surface texture meets specifications prior to coating by
using appropriate measurement instruments.
2.5.5 Visually inspecting surface for roughness
In the absence of physical profile measurement equipment, confirm
that part meets visual reference standard requirements prior to
commencing coating operations.
Properly handle and store workpiece,
2.6.1 Maintain surface cleanliness or work piece
Ensure that component surfaces for coating have not been
contaminated between abrasive blasting and coating operations.
2.6.2 Ensure rigging/hoist equipment is clean by visual
inspection before use and cleaning after use
Check to be sure that rigging/hoist equipment will not contaminate
part during handling prior or after coating operations.
2.6.3 Use appropriate personal protection equipment.
Ensure that proper personal protective equipment is selected and
utilized for abrasive blasting and coating operations.
2.6.4 Store rigging/hoist equipment in clean area. – this point is
covered in 2.6.2 above
Properly handle and store feedstock materials
2.7.1 Wear recommended safety equipment
Select appropriate safety equipment for abrasive blasting and
coating operations.
2.7.2 Ensure correct PPE used for particular feedstock
Select proper PPE according to its capability and capacity to
protect the wearer from harm.
2.7.3 Distinguish between feedstocks and their specific
requirements
Develop knowledge of feedstocks and ensure that correct materials
are being used and conform to specifications and work instructions
and router requirements
2.7.4 Assess powder to ensure it meets requirements of the work
instruction.
Verify that feedstock material is correct for the assigned work.
2.7.5 Identify sources of powder contamination
Check to be sure that issued feed stock is clean and dry, free from
foreign material and that powder feeders and lines to powder ports
have been cleaned prior to loading new powder.
2.7.6 Preheat or dry powder as required
Verify that powder has been dried or preheated in accordance with
work instructions and specifications in router and job
requirements.
2.7.7 Consult MSDS to assess hazardous qualities of powder
being used
Check MSDS sheets to be aware of any hazard issues relating to
the material issued; also check job documentation for the same.
2.7.8 Contain and remove spilled powder in safe manner
Clean work area of all spilled powder in accordance with local
regulations for handling and disposal of that material; Consult
MSDS sheets.
2.7.9 Properly reclaim excess powder.
Excess powder in the feeder that is not contaminated should be
properly returned to correct container so as to avoid
contamination.
2.7.10 Examine wire feedstock for any inconsistencies
Check wire feedstock for uniformity of coil and freedom from kinks
or nicks which would create feeding problems.
2.7.11 Consult MSDS for specific feedstock storage instructions
Review MSDS data sheets and company documents for proper
feedstock storage instructions.
2.7.12 Dispose of hazardous waste according to local regulations.
Ensure that all hazardous waste is collected and disposed of in
accordance with local and company regulations. When in doubt,
check with supervision and or company safety officer.
3 Spray equipment operation and maintenance (20% of
examination)
3.1
3.2
Set up thermal spray machinery and equipment
3.1.1 Identify equipment components by function.
Develop knowledge of all equipment components and their
functions.
3.1.2 Visually inspect for condition and replace if necessary.
Verify through visual inspection that all hardware is free from
damage that could cause malfunction. Replace any questionable
parts.
3.1.3 Ensure appropriate gas flows for work being performed
Before initiating torch operation, verify that gas flows are correct
in accordance with established parameters.
3.1.4 Ensure feedstock flowing appropriately
Verify proper feeding of feedstock and conduct “gram check”
prior to beginning coating operation
3.1.5 Confirm inputs to device are appropriately hooked up and
working
Review equipment set up and confirm that all connections are
correct and secure.
3.1.6 Follow sequence of operation
Review equipment start up procedure; confirm torch manipulation,
and part surface speeds.
3.1.7 Configure equipment to perform required operation.
Set up equipment in accordance with established parameters in
accordance with job documentation and work instructions.
Operate thermal spray equipment
3.2.1 Differentiate between thermal spray processes
3.3
3.4
Develop knowledge of each thermal spray process and how they
differ in terms of coating characteristics and performance as well
as the equipment requirements
3.2.2 Identify major/key equipment components
Correctly identify all major/key equipment components and their
function.
3.2.3 Differentiate the components by function.
Correctly identify all major/key equipment components and their
function.
3.2.4 Identify equipment parts that are configurable
Correctly identify all major/key equipment components and their
function.
3.2.5 Explain how changing configurations changes function.
Correctly explain how changing equipment configurations
influence coating characteristics by changing their function.
3.2.6 Perform necessary calculations such as oxy/fuel ratio.
Correctly calculate fuel gas ratios and how they influence coating
characteristics.
3.2.7 Select appropriate equipment for jobs being performed
Correctly select appropriate equipment for part coating in
accordance with job documentation and specifications.
3.2.8 Differentiate between controllers
Correctly identify different equipment controllers and their
functions.
3.2.9 Differentiate between feeders
Correctly identify different feedstock feeders, their set up and
function.
Maintain thermal spray machinery and equipment
3.3.1 Visually inspect machinery and equipment for condition
and replace if necessary.
Review and inspect equipment for possible damage or worn parts
and replace as necessary
3.3.2 Calibrate control equipment
Ensure that all equipment is properly calibrated and that all
feedstock controllers are properly set for appropriate federates in
accordance with established coating parameters.
3.3.3 Leak test equipment
Verify that all equipment is free from leaks – both liquid and gas
and all fittings are secure.
Troubleshoot and repair machinery and equipment
3.4.1 Follow basic maintenance procedures.
Perform detailed assessment of the problem to isolate its location
and issue, document findings and notify supervisor.
3.4.2 Identify and isolate problems
From trouble shooting guide and assessment of problem seek to
isolate the issue and identify its cause.
3.4.3 Correct problems
When capable correct malfunction, but in each case document the
issue and notify supervision
3.4.4 Wear appropriate PPE.
Select proper PPE according to its capability and capacity to
protect the wearer from harm.
3.4.5 Stop process or fix problem while spraying continues.
When problem or issue is identified, stop coating process if needed
or fix problem while spraying continues. Document the issue and
notify supervision.
3.4.6 Identify when partial interruptions impact coating
Check to be sure that when interruptions occur that coating is not
adversely affected. Notify supervision when issue is found and
coating is compromised.
3.4.7 Identify problems with robotic systems
Monitor equipment and robotic handling systems for proper
functioning.
3.4.8 Reset system
Familiarize yourself with the robotic control system and when it
needs to be reset.
3.4.9 Visually observe spray plume for normal operation.
Monitor spray plume for changes from normal operation and look
for possible problems with the coating operation and quality.
4 Application of Coating (30% of examination)
4.1
Assess personnel and surrounding safety
4.1.1 Verify the job/part specific requirements
Confirm and verify that the component to be processed matches the
item defined in the job router packet in terms of the dimensions
and specifications for coating and process plan. Notify supervision
of all discrepancies.
4.1.2 Determine safety requirements for the process; i.e., powder,
gas, wire, etc.
Rate hazards present in work space for particular job being
performed. Know what regulations (federal, state, local) apply
4.1.3 Determine hazards present.
Perform more detailed assessment of hazards posed by equipment,
materials, energy sources, spatial area, personnel and other
sources of hazard.
4.2
Set up spray equipment
4.2.1 Select manual or mechanical process
Review and evaluate part, process documentation and available
equipment for appropriate process.
4.2.2 Set up spray gun according to method selected
Mount and position gun or torch for appropriate stand off from
work in accordance with established parameters.
4.3
4.4
4.5
4.2.3 Set up feeder according to method selected
Prepare powder feeder with assigned material and hardware per
established parameters.
4.2.4 Determine and verify powder feed rate
Conduct gram check and make adjustments to bring feed rate
within parameter requirements.
4.2.5 Align spray gun and part with proper standoff distance.
Confirm position and alignment of gun is in accordance with
required parameter specifications.
4.2.6 Determine spray pattern
Ensure that spray pattern conforms to coating requirement and
established parameters.
4.2.7 Verify spray pattern parameters are correct.
Confirm spray pattern achieves planned coverage per job router
plan and work instructions and equipment parameter settings are
correct per these specifications.
Verify materials used for coating
4.3.1 Verify the job/part specific requirements
Ensure that component conforms to the job routing and
documentation specifications.
4.3.2 Select materials according to job documentation.
Ensure that materials conform to the job routing and
documentation specifications.
4.3.3 Wear/use personnel safety equipment specified.
Select proper PPE according to its capability and capacity to
protect the wearer from harm
Prepare work piece for manual spraying
4.4.1 Secure part for proper manipulation as necessary.
Mount and secure part in equipment for correct standoff and
movement before gun in accordance with process plan
documentation.
4.4.2 Correctly position spray equipment to large workpiece as
specified, using proper standoff distance, spray equipment
orientation to work piece
Ensure work piece, gun are in proper position and orientation for
coating operation per job router and process document
requirements.
4.4.3 Control substrate temperature.
Check part temperature before and during coating operations and
maintain temperature range within established parameters.
Fix of mount workpiece for mechanized spraying
4.5.1 Select robotic program for spray.
Review available robotic programs and select designated program
for part per job routing documentation or one that maintains gun
to work relationship requirements in coating parameters: standoff,
angle of spray, traverse speeds.
4.5.2
4.6
4.7
Adjust nozzle angle for optimum thickness and adherence
control
Confirm that gun nozzle angle to work piece is in accordance with
established parameters and work instructions.
4.5.3 Adjust nozzle angle for optimum spray geometry (inside
angles, e.g.).
Ensure gun nozzle angle will provide optimum coating coverage.
4.5.4 Confirm program provides appropriate movement of spray
gun.
Prior to beginning actual spray operation, verify with “dry run”
that all gun to work movements are in accordance with plan.
Perform job specific measurements
4.6.1 Assess initial substrate coating thickness
Verify and record part incoming dimensions with appropriate
measuring instrument.
4.6.2 Verify measurement at end of spray for each part
Verify and record part dimensions with appropriate measuring
instrument after coating process is in accordance with plan.
4.6.3 Verify measurements while job in process and/or at
completion as appropriate
Confirm part measurement during coating process to assure part
is in compliance with process plan.
4.6.4 Document spray thickness during process
Record part dimensions at start, during, and at end of coating
process to document coating thickness.
4.6.5 Measure part temperature
Use a pyrometer or infrared temperature device to record
temperatures of part at start, during, and at end of coating
process.
4.6.6 Measure thickness of spray coating using micrometers or
eddy current tests for example
Verify coating thickness using micrometer or other eddy current
type equipment.
4.6.7 Obtain metallographic sample for submission to lab
Verify coating quality by processing a sample tab with part that
can be submitted to lab for evaluation.
4.6.8 Perform visual inspection of spray coating
Conduct visual inspection of coating and document findings.
Monitor spray process before packaging
4.7.1 Stop process for minor corrections, such as overspray,
visual inspections, measurements
Conduct in process quality control checks and make minor
corrections as needed to achieve process plan specifications.
4.7.2 Measure depth of spray coat using appropriate tools
(calipers, micrometers, etc.)
4.8
4.9
Verify coating thickness using appropriate measuring tools –
micrometers or eddy current thickness gages.
4.7.3 Ensure stoppage does not exceed maximum allowable limit
Verify that any interruptions in the coating process do not cause
delays that would exceed any specified time constraint
requirements of the coating process specifications.
4.7.4 Operate equipment manually to perform non-automated
functions, adjust controls to correct malfunctions or out-oftolerance processes, and when automatic programming is
faulty or equipment malfunctions.
Confirm with supervision or process plan documents that manual
spraying may or may not be used for minor touch up operations or
when robotic programming is malfunctioning.
Perform post-coating processing as specified
4.8.1 Heat treat to remove any polymer mix
Verify with process plan documents and specifications if heat
treating may be used to remove any polymer mixes in component
as a result of coating operations.
4.8.2 Cure coating
Ensure that any post-coating curing operations are conducted in
accordance with process parameters and plans.
4.8.3 Apply sealer to coating
Verify when indicated the sealer to be used for coating after
processing.
4.8.4 Grind or machine coating to comply with work instruction
Check process documents for any grinding or machining
operations following coating application. Execute in compliance
with process documentation.
4.8.5 Perform other treatments as required, e.g., heat treatment,
peening.
Check to be sure what other post coating process treatments are
required for component with job router and process specifications.
Remove masking
4.9.1 Visually inspect to ensure removal did not affect spray
coating
Verify that demasking operations did not damage coating.
4.9.2 Dispose of masking properly according to safety
instructions
Ensure that masking materials are disposed of in accordance with
local regulatory requirements.
4.9.3 Flag any deviations from job requirements
Document and notify supervisor about any deviations found on the
parts.
4.9.4 Take corrective actions to correct deviations from job
requirements
4.10
4.11
Review discrepant part and process to determine what actions
could lead to improved processes and correct deviations on future
parts.
Tear down job and store materials properly
4.10.1 Replace materials in proper place
Ensure that all raw materials and tools are returned to their
proper storage locations upon completion of work.
4.10.2 Weigh materials to determine job usage.
Verify and record weight of remaining raw materials after usage.
4.10.3 Shut down equipment according to procedures.
Close or shut down equipment in proper sequence according to
manufacturer’s suggestions and work safety concerns
4.10.4 Maintain clean environment
Clean up work area after processing parts; properly dispose of all
overspray materials.
4.10.5 Remove and store job specific tooling.
Clean and return all tooling to appropriate location for future use.
Package and store workpiece at end of process
4.11.1 Follow work instruction requirements
Ensure that completed parts are properly packaged according to
work instructions or job routing specifications following coating
operations.
4.11.2 Protect piece from damage.
Check to be sure coated part is properly protected from damage
following coating operation.
5 Record keeping and quality control (10% of examination)
5.1
Make in-process quality control measurements
5.1.1 Make and record initial measurement prior to applying
coating
Document and record part dimensions before coating. Make note
of any discrepancies from process plan documentation.
5.1.2 Make and record measurements during and after applying
coating.
Document and record part dimensions after coating. Make note of
any discrepancies from process plan documentation.
5.2
Document work results
5.2.1 Collect and log in results of visual inspection
Document and record results of visual inspection as required by
process documents.
5.2.2 Systematically log measurements taken during process
Document and record all in-process measurements
5.2.3 Record data related to any testing
Document and record testing data and parameters in accordance
with process document requirements.
5.2.4 Record testing parameters.
Document and record testing data and parameters in accordance
with process document requirements