SAQA All qualifications and part qualifications registered on the National Qualifications Framework are public property. Thus the only payment that can be made for them is for service and reproduction. It is illegal to sell this material for profit. If the material is reproduced or quoted, the South African Qualifications Authority (SAQA) should be acknowledged as the source.
SOUTH AFRICAN QUALIFICATIONS AUTHORITY 
REGISTERED UNIT STANDARD THAT HAS PASSED THE END DATE: 

Select and fit seals in fluid power applications 
SAQA US ID UNIT STANDARD TITLE
244704  Select and fit seals in fluid power applications 
ORIGINATOR
SGB Manufacturing and Assembly Processes 
PRIMARY OR DELEGATED QUALITY ASSURANCE FUNCTIONARY
-  
FIELD SUBFIELD
Field 06 - Manufacturing, Engineering and Technology Manufacturing and Assembly 
ABET BAND UNIT STANDARD TYPE PRE-2009 NQF LEVEL NQF LEVEL CREDITS
Undefined  Regular  Level 3  NQF Level 03  6 
REGISTRATION STATUS REGISTRATION START DATE REGISTRATION END DATE SAQA DECISION NUMBER
Passed the End Date -
Status was "Reregistered" 		 2018-07-01  2023-06-30  SAQA 06120/18 
LAST DATE FOR ENROLMENT LAST DATE FOR ACHIEVEMENT
2024-06-30   2027-06-30  

In all of the tables in this document, both the pre-2009 NQF Level and the NQF Level is shown. In the text (purpose statements, qualification rules, etc), any references to NQF Levels are to the pre-2009 levels unless specifically stated otherwise.  

This unit standard does not replace any other unit standard and is not replaced by any other unit standard. 

PURPOSE OF THE UNIT STANDARD 
The skills, values and knowledge reflected in this unit standard are required by people in the field of Fluid Power Engineering who are required to select and fit seals in Fluid Power applications. The learning outcomes in this unit standard also contribute to the exit level outcomes required for the fluid power NQF Level 3 qualification.

Persons credited with this unit standard are able to:
  • Demonstrate understanding of the different types of seals and seal materials.
  • Demonstrate understanding of the use of seals in fluid power.
  • Fit different types of seals.
  • Conduct failure analysis of seals and O rings. 
    		•

    LEARNING ASSUMED TO BE IN PLACE AND RECOGNITION OF PRIOR LEARNING 
    The credit calculation is based on the assumption that a person is already competent in terms of the following outcomes when starting to learn toward this unit standard:
  • Select, use and care for engineering hand tools at NQF Level 2.
  • Select, use and care for engineering measurement equipment at NQF Level 2.
  • Assemble mechanical components at NQF Lvel 2.
  • Read and interpret engineering drawings at NQF Level 2. 
    		•

    UNIT STANDARD RANGE 
    The following scope and context applies to the whole unit standard:
  • This standard is limited to seals and O rings used in conjunction with fluid power products.
  • Seals falling under this standard are rod seals, rotating shaft seals, piston seals (both single and double acting), vee packing kits, wiper seals, wear strips and O rings.

    Specific range statements are provided in the body of the unit standard where they apply to particular specific outcomes or assessment criteria. 
    		•

    Specific Outcomes and Assessment Criteria: 

    SPECIFIC OUTCOME 1 
    Demonstrate understanding of the different types of seals and seal materials. 

    ASSESSMENT CRITERIA     

    ASSESSMENT CRITERION 1 
    The most common basic elastomers used in fluid power seals are identified and described in terms of material properties. 
    ASSESSMENT CRITERION RANGE 
    Materials include, butyl rubber, EPDM, FKM, nitrile or buna N, neoprene and polyurethane.
     

    ASSESSMENT CRITERION 2 
    Shore hardness is explained in terms of its effect on seal compression and friction. 

    ASSESSMENT CRITERION 3 
    The effects of temperature on the lifetime of the seal are explained in relation to the type of material used. 

    ASSESSMENT CRITERION 4 
    The compatibility of different seal materials with the different fluids and cleaning agents are identified in accordance with manufacturer specifications. 

    ASSESSMENT CRITERION 5 
    Methods of storing seals and materials are described in terms of type of storage method and the effect on the usable life of the material. 

    SPECIFIC OUTCOME 2 
    Demonstrate understanding of the use of seals in fluid power. 

    ASSESSMENT CRITERIA     

    ASSESSMENT CRITERION 1 
    The size of a seal and groove is confirmed to be in accordance with manufacturer specifications. 

    ASSESSMENT CRITERION 2 
    The purpose of using a back up ring with an O ring seal is explained in relation to specific circumstances and operating conditions. 

    ASSESSMENT CRITERION 3 
    Seals are selected for different operating conditions in accordance with manufacturer specifications. 

    ASSESSMENT CRITERION 4 
    Surface roughness is explained in relation to its effect on seal life. 

    ASSESSMENT CRITERION 5 
    Minimum and maximum extrusion gaps for hydraulic and pneumatic cylinder rods and pistons are explained in terms of fluid power principles. 

    ASSESSMENT CRITERION 6 
    Friction is explained with respect to seals in a dynamic situation. 

    SPECIFIC OUTCOME 3 
    Remove and fit seals to fluid power components. 

    ASSESSMENT CRITERIA     

    ASSESSMENT CRITERION 1 
    The seal housing is checked for condition and confirmed to be suitable for fitting of the seal. 

    ASSESSMENT CRITERION 2 
    Fitment of seals is conducted without causing damage to the seal. 
    ASSESSMENT CRITERION RANGE 
    Over threads and ports and in to grooves.
     

    ASSESSMENT CRITERION 3 
    Seals are removed from their positions without causing unnecessary damage to the component or seal. 

    ASSESSMENT CRITERION 4 
    Work is conducted in accordance with workplace safety requirements. 

    ASSESSMENT CRITERION 5 
    Tools and equipment are used in accordance with their design. 

    ASSESSMENT CRITERION 6 
    The consequences of not fitting the correct seal are explained in terms of potential safety hazards and production interruptions. 

    SPECIFIC OUTCOME 4 
    Inspect and evaluate condition of seals. 

    ASSESSMENT CRITERIA     

    ASSESSMENT CRITERION 1 
    The condition of a seal is evaluated and reported on in accordance with workplace requirements. 

    ASSESSMENT CRITERION 2 
    The different types of failures on a seal are explained in terms of cause and prevention. 
    ASSESSMENT CRITERION RANGE 
    Spiral failure, abrasion, weathered, hardening and oxidation, installation damage, extrusion, normal wear, fluid incompatibility.
     

    ASSESSMENT CRITERION 3 
    The most probable cause of failure on seals is identified in accordance with workplace and manufacturer's requirements. 


    UNIT STANDARD ACCREDITATION AND MODERATION OPTIONS 
  • Anyone assessing a learner against this unit standard must be registered as an assessor with the relevant ETQA.
  • Any institution offering learning that will enable achievement of this unit standard must be accredited as a provider through the relevant ETQA by SAQA.
  • Moderation of assessment will be overseen by the relevant ETQA according to the moderation guidelines and the agreed ETQA procedures. 
    		•

    UNIT STANDARD ESSENTIAL EMBEDDED KNOWLEDGE 
    Essential embedded knowledge will be assessed through assessment of the specific outcomes in terms of the stipulated assessment criteria. Candidates are unlikely to achieve all the specific outcomes, to the standards described in the assessment criteria, without knowledge of the listed embedded knowledge. This means that for the most part, the possession or lack of the knowledge can be directly inferred from the quality of the candidate's performance. Where direct assessment of knowledge is required, assessment criteria have been included in the body of the unit standard.

    The following embedded knowledge is addressed in an integrated way in the unit standard:
  • How to identify and measure seals and grooves.
  • Different types of seals.
  • Chemistry effect of different fluids on different seal materials.
  • Methods of cleaning sealing arrangements.
  • How to fit a seal into a fluid power system.
  • How to select a seal for a fluid power system. 
    		•

    UNIT STANDARD DEVELOPMENTAL OUTCOME 
    N/A 

    UNIT STANDARD LINKAGES 
    N/A 


    Critical Cross-field Outcomes (CCFO): 

    UNIT STANDARD CCFO IDENTIFYING 
    Identify and solve problems and make decisions using critical and creative thinking.

    Note:
  • The ability of the candidate to identify problems in relation to the failure of a fluid power seal. 
    		•

    UNIT STANDARD CCFO WORKING 
    Work effectively with others as members of a team, group, organisation or community. 

    UNIT STANDARD CCFO ORGANISING 
    Organise and manage themselves and their activities responsibly and effectively.

    Note:
  • The ability of the candidate to prepare a unit for fitting of a sealing system. 
    		•

    UNIT STANDARD CCFO COLLECTING 
    Collect, analyse, organise and critically evaluate information.

    Note:
  • The ability of the candidate to evaluate the correctness of a fluid power sealing system. 
    		•

    UNIT STANDARD CCFO COMMUNICATING 
    Communicate effectively, using visual, mathematical and/or language skills in the modes of oral and/or written presentations.

    Note:
  • The ability of the candidate to report condition of seals. 
    		•

    UNIT STANDARD CCFO SCIENCE 
    Use science and technology effectively and critically showing responsibility towards the environment and health of others.

    Note:
  • The ability of the candidate to use technical equipment in fitting fluid sealing systems and interpret reference material. 
    		•

    UNIT STANDARD CCFO DEMONSTRATING 
    Demonstrate an understanding of the world as a set of related systems by recognising that problem-solving contexts do not exist in isolation.

    Note:
  • The ability of the candidate to identify the effects of a poor sealing system in a fluid power circuit. 
    		•

    UNIT STANDARD ASSESSOR CRITERIA 
    N/A 

    REREGISTRATION HISTORY 
    As per the SAQA Board decision/s at that time, this unit standard was Reregistered in 2012; 2015. 

    UNIT STANDARD NOTES 
    Terminology:

    The following terms are specific to the industry, and are defined as follows:
  • EPDM: Ethylene propylene rubber.
  • FKM: Fluorocarbon rubber.

    Notes to Assessors:

    Assessors should keep the following principles in mind when designing and conducting assessments against this unit standard:
  • Focus the assessment activities on gathering evidence in terms of the main outcome expressed in the title to ensure assessment is integrated rather than fragmented. Remember we want to declare the person competent in terms of the title. Where assessment at title level is unmanageable, then focus assessment around each specific outcome, or groups of specific outcomes.
  • Make sure evidence is gathered across the entire range, wherever it applies. Assessment activities should be as close to the real performance as possible, and where simulations or role-plays are used, there should be supporting evidence to show the candidate is able to perform in the real situation.
  • Do not focus the assessment activities on each assessment criterion. Rather make sure the assessment activities focus on outcomes and are sufficient to enable evidence to be gathered around all the assessment criteria.
  • The assessment criteria provide the specifications against which assessment judgements should be made. In most cases, knowledge can be inferred from the quality of the performances, but in other cases, knowledge and understanding will have to be tested through questioning techniques. Where this is required, there will be assessment criteria to specify the standard required.
  • The task of the assessor is to gather sufficient evidence, of the prescribed type and quality, as specified in this unit standard, that the candidate can achieve the outcomes again and again and again. This means assessors will have to judge how many repeat performances are required before they believe the performance is reproducible.
  • All assessments should be conducted in line with the following well documented principles of assessment: appropriateness, fairness, manageability, integration into work or learning, validity, direct, authentic, sufficient, systematic, open and consistent. 
    		•

    QUALIFICATIONS UTILISING THIS UNIT STANDARD: 
      ID QUALIFICATION TITLE PRE-2009 NQF LEVEL NQF LEVEL STATUS END DATE PRIMARY OR DELEGATED QA FUNCTIONARY
    Core  58882   National Certificate: Fluid Power  Level 3  NQF Level 03  Passed the End Date -
    Status was "Reregistered"     		 2023-06-30  MERSETA 
    Elective  78524   National Certificate: Automotive Repair and Maintenance  Level 3  NQF Level 03  Passed the End Date -
    Status was "Reregistered"     		 2023-06-30  As per Learning Programmes recorded against this Qual 


    PROVIDERS CURRENTLY ACCREDITED TO OFFER THIS UNIT STANDARD: 
    This information shows the current accreditations (i.e. those not past their accreditation end dates), and is the most complete record available to SAQA as of today. Some Primary or Delegated Quality Assurance Functionaries have a lag in their recording systems for provider accreditation, in turn leading to a lag in notifying SAQA of all the providers that they have accredited to offer qualifications and unit standards, as well as any extensions to accreditation end dates. The relevant Primary or Delegated Quality Assurance Functionary should be notified if a record appears to be missing from here.
     
    NONE 


    All qualifications and part qualifications registered on the National Qualifications Framework are public property. Thus the only payment that can be made for them is for service and reproduction. It is illegal to sell this material for profit. If the material is reproduced or quoted, the South African Qualifications Authority (SAQA) should be acknowledged as the source.