Maintainability-Planning and Scheduling

Maintainability

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What is Maintainability Maintainability ? The U.S. U .S. Department of Defense De fense publication, publication, MIL-HDBK-470A, dated dated 4 August August 1997, 1997 , “The ability of an item to be retained in, or restored to, a specified condition when maintenance ma intenance is performed performed by personnel having specified skill levels, using prescribed procedures and resources, at each prescribed level of maintenance and repair” Wikipedia (for telecommunications) •

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“A characteristic characteristic of design and installation, insta llation, expressed as the probability that an item will be retained or restored to a specified condition within a given period of time, when maintenance is performed in accordance with prescribed procedures and resources.

The ease with which maintenance of a functional unit can be performed in accordance with prescribed requirements.” requirements.” 2

Downtime State

Time of Failure Run-

Preparation

down and/or delay

Uptime

Active Maintenance time

Downtime

Waiting and Ramp/or delay

up

Uptime

Time

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Maintainab Maintainabilit ility y is About … •

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Design Logistic Location / Space

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Work Process

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Work Scope

• • • •

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Leadership Skill Communication Technology Policy

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Maintainab Maintainability ility Metrics Mean Time T ime to Repair Repair (MTTR)

The arithmetic arithmet ic aver average age of the maintenance cycle times for for the individual individual maintenance actions actions of a system (excludes preventive maintenance)

Mean Down Time (MDT)

The mean m ean or avera average ge time t ime that a system is not operational due to repair or preventive maintenance. This includes includes logistics and administrative administrative delays.

Planning and Scheduling

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Total Maintenance Cost Ratio Planned Maintenance

Minimum Cost

Unplanned Maintenance

1.5 Times Minimum Cost

Breakdown Maintenance

3-9 Times Minimum Cost

You can hear unplanned u nplanned maintenance m aintenance by listening to craftspeople … Who’s available ? Where’s the parts? How did they do it last time ? Where’s the lock -out? How late is the order now ?

Planning and Scheduling improve improve Productivity 13% Personal

10% Clerical

15% Waiting for Jobs

22% Travel time and Stores

10% Waiting for Instructions

30% Production Work

Before Controlled Maintenance

Reduce by 30%

50% Production Work

60% Increase in Productivity

After Controlled Maintenance

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Planning and Scheduling A poll of planner/schedulers taken over a 10 year period indicated the following ollow ing breakdown of an average average workday Planning and Estimating Jobs

20-30%

Scheduling

15-25%

Purchasing and Expediting Parts

20-30%

Other Duties

25-35%

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• • • • • • •

Inspection Predictive Preventive CBM Corrective Lubrication Repair 

Work identification

Requisition Specify

Work Planning

Work Scheduling

Equipment Control

Source

Equipment  Arrangem  Arrangement ent

Order 

Bills of Material Work  Assignment  Assignment    k   c   a    b    d   e   e    F

Receiving Report

   k   c   a    b    d   e   e    F

Store

Control Repairables

Work Execution

Delivery Delivery of  Materials Materials to Specific Drop Drop site s ite

W ork Analysis Analysis

Use

 Analyse  Analyse

Reporting 10

Planning is the allocation of needed resou resource rcess and the sequence in which they are needed, to allow an essential essentia l activity to be performed in the shortest time or at the least cost. Purpose To ensure ensure that all the resources and information necessary to do do the job are a re accounted accoun ted for

Failing to Plan = Planning to Fail

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Resources •

Labor Labo r & Crew Size & Skill Skill

•

Materials , Parts & Supplies

•

Tools

•

Support Equipment Equipment

•

•

Contracted (Outside) Services Time

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What does a job plan contain ?

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Work Planning •

A Process in which which work is is  –

Estimated

 –

Assigned resources

 –

Given detailed safety procedures

 –

Given work procedures

 –

Documented and interfaced with the scheduling element

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Planning and Estimating Methods •

Construction Planning and Estimating

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Method Time Measure Measu rement ment

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Planning Thought Pr Process ocess

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Estimates Based on Past Performance Performance

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Planning Thought Thought Process Inspect the equipment and site

What must happen first on this job ?

Who must do this step ?

What must happen next on this job ?

What safety /environmental precaution are required ?

How many people are required ?

How long will it take ?

What Parts , Material , or Supplies will be needed ?

Is any support equipment required ? 16

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Estimating using past performance •

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•

•

•

•

Problem

Completed hours charged to historical records may may be inaccura inacc urate te History records may may not document docu ment all parts used on the job History records do not capture other resources Historical record may may not n ot capture outside services Closure notes on historical hist orical records do not clarify actual work performed 18

Improving Improving the History Record Record •

Write WO for all al l maintenance main tenance activities

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Charge parts and materials materials to WO only o nly

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Charge Charge outside outsid e services to a WO

•

•

•

Provide a means to capture cap ture undocumented undocumented resources Enlist meaningful meaningful comments comments on the work w ork performed Use WO to update equipment database information 19

Standard Job Plan

A Planner should never have to plan the same job twice

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Scheduling •

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Is the assignment of many planned jobs into a defined period of time in order to optimize the use of the resour resources ces within their constraints placing an identified need for work on a formal work list at least le ast two days days prior to the day that the work is to begin

A Backlog Backlog of work is require required d 23

Resource Constraints Constraints •

Fixed Amount Amount of Labor La bor

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Limited Limited or or Special Skills

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Space

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Physical Properties

•

•

Rules and an d Regulations Regulations Money

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Scheduling •

•

Can be based on a work order backlog of jobs that are not no t linked to each other other but have different different import impo rtance ance (entity criticality , WO priority and WO class) Can be based on activiti activities es or work order orderss from a project project , turnaround or shutdown where job job importance impo rtance and the timing of when wh en they are done in relation to each other is critical 25

The Criteria utilized •

•

•

Work group net capacity capa city / Calendar Calend ar Work order o rder priority priority and cycle cycle time of the work w ork order Opportunities of an equipment shutdown +

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Priorit Priority y System System The Drawbacks of not Clearly Defining Priorities Priorities •

•

•

•

Wasted maintenance maintenance man-hours on tasks of  low relative relative importance importance Critical tasks tasks being lost in maintenance backlog Dissatisfied Dissatisfied operations customers Lack of faith in the effectiveness effectiveness of the maintenance maintenance delivery functions 27

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Scheduling •

A Schedule is a communication communication document document  –

Operation

 –

Store

 –

Supervisor

 –

Contractors

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To Schedule Work •

•

•

•

Identify Preventive maintenance and corrective c orrective backlog by:  –

Equipment

 –

Priority

 –

Due Date

Determine Availa Availabili bility ty of skill sk illss and resources res ources Look at production’s production’s equipment operating operating Schedules Sc hedules for the period and attempt attem pt to match their plan

Balance Balance the work list against against the resources  –

•

(both internal & external)

Agree to schedule sc hedule with operations , modify as required prior to issue to the work shop 32

Weekly Schedule Schedule Developed at the weekly scheduling meeting

Input from  –

Maintenance first-line supervision

 –

Scheduler

 –

Planner

 –

Maintenance Manager

 –

Operations Representatives

Provide maintenance supervision with work orders The work orders selected are based on cycle time and priority 33

Schedule Schedule Development Development •

Planner/Scheduler Planner/Scheduler distributes backlog backlo g  –

Operations reviews list  – picks work

 –

Maintenance reviews list picks work

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Engineering Engineerin g provides provides list of of work required

•

Maintenance Maintenance provides craft craft availa availability bility

•

Planner Planner triggers PM’s PM’s

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List returned to Planner/Sch Plan ner/Scheduler eduler with selection 34

•

•

Planner/Sched Planner/Scheduler uler builds builds tentative tentative schedule  –

PM’s due

 –

Operations’ picks

 –

Maintenance picks

 –

Engineering requirements

Planner/Sched Planner/Scheduler uler adds add s activities from backlog back log until craft availa availability bility is full ful l  –

•

Highest priority  – oldest cycle time

Reviewed and agreed to at weekly weekly meeting meeting (Friday Afternoon) 35

Weekly Schedules

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Daily Schedule •

•

•

•

Built by maintenan maintenance ce first-line supervisors superviso rs Uses the work work orders orders identified on the weekly schedule Includes assigned as signed crafts crafts personnel personnel Urgent work orders orders placed placed on schedule schedule for the following day

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Daily schedule review meeting 10 minute meeting held daily in the afternoon Attended by  –

Maintenance first line supervision

 –

Maintenance scheduler

 –

Engineering

Review the status of the work scheduled for that day

Review the work scheduled for the following day Insert any urgent work requests that ready for scheduling 38

•

•

Fixed agenda  –

Safety issues

 –

Past 24 hours

 –

Next 24 hours  – including any urgent work added

All problem solving off-line

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Daily Schedules

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Contractors Contractors are are generally generally brought in for maintenance on 3 occasions  –

 –

 –

Special skills are required that are not represented repres ented in the t he normal maintenance work force. The maintenance m aintenance backlog is excessive excess ive and critical work is not being completed on time. Contractors are used to work the backlog back log down A unique situation (Shutdown (Shutd own or turnaround) requires crewing levels levels far far above the facility facility maintenance work force.

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Best Practice There is a well defined , comprehensive schedule schedule of maintenance maintena nce activities for all areas of the facility •

Compliance to Pm/PdM Pm/PdM schedule is > 95%

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Overall Overall schedule schedule compliance complian ce is >90%

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A minimum of 45% 45 % of availa available ble personn personnel el are are scheduled for for planned 80% of available available manpower is scheduled on a weekly basis 42

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Weekly meetings for creating the th e upcoming upcomin g week’s week’s work schedul schedule e All meetings at a ttended by Maintena M aintenance nce , Operations Operations and Engineering department department representatives for the area. 100% available available manpower is scheduled on a daily basis Daily schedule review review meeting held to confirm con firm upcoming upcoming day’s day’s work

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Performance erformance Measurement Indicator

Backlog

Formula

Backlog hours Hours in a work week x No. of Available Craftspeople

Planned & Schedule Compliance

Schedule hours actually worked Total Hours Scheduled

% Emergency Work

Total Emergency worked (hours) Total hours worked

Overtime

Total overtime worked (hours) Total hours worked

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Conclusion Key Roles and Relationships •

Planner = what to do

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Scheduler = when to do it

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Supervisor = who to do it

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Craftsper Craftsperson son = How to do it

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