Machine Design, Materials and Shop Practice
30%of exam
Industrial and Power Plant Engineering
35%of exam
Mathematics, Engineering Economics and Basic Engineering Sciences
35%of exam
Quick Facts
- Exam
- MELE
- Board
- PRC Board of ME
- Law
- RA 8495
- Items
- 300 total, 100 per subject
- Schedule
- 3 days, 8AM-2PM daily
- Pass
- 70% average
- Floor
- No subject below 50%
- Calculator
- Non-programmable only
- Retake
- 1 year after third fail
- Feb 2026 passers
- 51.86% (3,264/6,294)
- Blueprint
- Resolution 57, s. 2013
Column End Fixity
Fixing halves it, freeing doubles it
Pinned-pinned: 1.0Fixed-fixed: 0.5Fixed-pinned: 0.7Fixed-free: 2.0
Soderberg vs Goodman
Soderberg
- Uses yield strength Sy
- Most conservative line
- No yielding permitted
Goodman
- Uses ultimate strength Su
- Allows higher mean stress
- Standard fatigue line
Yield line vs ultimate
Machine Element Picker
- Rotating power transmission→Shaft torsion formula(16T / (pi d^3))
- Shaft sized by code→PSME cubic formula(C = 80/53.5/38)
- Torque through hub→Key shear and bearing(Weaker governs)
- Non-parallel shafts→Bevel or worm gears
- Long center distance→Belt or chain drive
- Exact ratio required→Chain or gear(Belts slip)
- Fluctuating stress→Soderberg or Goodman
- Long slender member→Euler buckling(Check slenderness first)
- Short compression member→J.B. Johnson formula
- Smoothing speed swings→Flywheel(Kinetic energy store)
MDMSP Item Counts
- Kinematics
- 12 items2.38%
- Machine Design
- 81 items25%
- Shop Machinery
- 3 items
- Shop Practice
- 4 items
- Subject total
- 100 items, 30% weight
- Design sub-areas
- 27 topics listed
- Each design topic
- 3 items apiece
PSME Shaft Constants
Main 80, line 53.5, short 38
P = D^3 N / CMain power shaft: 80Line shaft pulleys: 53.5Small short shaft: 38
Allowance vs Tolerance
Allowance
- Between mating parts
- Sets the fit type
Tolerance
- On one dimension
- Sets permitted variation
Fit type vs drift
Stress Formulas
- Axial stress
- P / A
- Direct shear
- V / A
- Bearing stress
- P / (t x d)
- Torsional shear
- 16T / (pi d^3)
- Bending stress
- M c / I
- Section modulus
- S = I / c
- Hoop stress
- p D / (2t)
- Longitudinal stress
- p D / (4t)
- Factor of safety
- Strength / working stress
Shafts, Keys, Couplings
- Power from torque
- P = 2 pi T N
- PSME main shaft
- P = D^3 N / 80
- PSME line shaft
- P = D^3 N / 53.5
- PSME short shaft
- P = D^3 N / 38
- Key tangential force
- F = 2T / D
- Key checked twice
- Shear and bearing
- Torsional deflection
- T L / (J G)
- Flange coupling bolts
- Shear on bolt circle
Gears
- Module
- m = D / N
- Circular pitch
- p = pi m
- Diametral pitch
- Pd = N / D
- Pitch identity
- p x Pd = pi
- Center distance
- (D1 + D2) / 2
- Velocity ratio
- N1 / N2 = T2 / T1
- Train value
- Driver teeth / driven teeth
- Idler gear
- Reverses direction only
- Mesh condition
- Same module required
Belts, Chains, Flywheels
- Tension ratio
- F1 / F2 = e^(mu theta)
- Belt power
- (F1 - F2) x speed
- Contact angle effect
- More wrap, more capacity
- V-belt advantage
- Wedging raises effective friction
- Flywheel energy
- KE = 0.5 I omega^2
- Coefficient of fluctuation
- Speed swing / mean speed
- Chain versus belt
- No slip, fixed ratio
Springs + Bearings
- Spring deflection
- 8 F D^3 n / (G d^4)
- Spring rate
- k = F / delta
- Wire diameter effect
- Stiffness varies d^4
- Wahl factor
- Corrects curvature shear
- Bearing rating life
- L10 = (C / P)^k
- Ball bearing k
- 3
- Roller bearing k
- 10/3
- L10 meaning
- 90% survive rating life
Bolts, Welds, Rivets
- Bolt torque
- T = K F d
- Nut factor K
- 0.20 dry, 0.15 lubricated
- Fillet weld throat
- 0.707 x leg
- Weld shear area
- Throat x length
- Rivet joint efficiency
- Joint strength / plate strength
- Rivet failure modes
- Shear, tear, crush
- Thread stress area
- Less than nominal area
Columns + Fatigue
- Euler load
- pi^2 E I / (K L)^2
- K pinned-pinned
- 1.0
- K fixed-fixed
- 0.5
- K fixed-pinned
- 0.7
- K fixed-free
- 2.0
- Slenderness ratio
- K L / r
- Short column rule
- Use J.B. Johnson
- Soderberg
- Uses yield strength Sy
- Goodman
- Uses ultimate strength Su
Materials + Shop Practice
- Cutting speed
- V = pi D N
- Spindle speed
- N = V / (pi D)
- Allowance
- Intended clearance or interference
- Tolerance
- Permitted variation, one dimension
- Annealing
- Softens, relieves internal stress
- Quenching
- Hardens, forms martensite
- Tempering
- Restores toughness after quench
- Eutectoid steel
- 0.8% carbon at 723 degC
- Brinell versus Rockwell
- Indent size versus depth
Subject Weights
Power 35 | Math 35 | Design 30
Power plant: 35%Math sciences: 35%Machine design: 30%100 items each
Load vs Capacity Factor
Load factor
- Average over peak load
- Measures demand steadiness
Capacity factor
- Average over rated capacity
- Measures plant utilization
Demand vs installed capacity
Plant + Cycle Picker
- Spark ignition engine→Otto cycle
- Compression ignition engine→Diesel cycle
- Gas turbine plant→Brayton cycle
- Steam turbine plant→Rankine cycle
- Wet turbine exhaust→Add reheat(Protects last blades)
- Need higher efficiency→Add regeneration(Feedwater heating)
- Turbine exhaust heat wasted→Combined cycle
- Pump losing suction→Check NPSHa(Must exceed NPSHr)
- Cutting fan power→Reduce speed(Power varies cubed)
- Two-stage compression→Intercool at geometric mean
IPPE Item Counts
- Power Plant Elements
- 11 items
- Power Plant Design
- 24 items
- Industrial Plant Engineering
- 13 items
- Industrial Plant Design
- 24 items
- Refrigeration
- 10 items
- Air Conditioning
- 18 items
- Subject total
- 100 items, 35% weight
- Refrigeration plus AC
- 28 of 100 items
- Industrial plant share
- 37 of 100 items
Affinity Laws
Flow one, head two, power three
Flow: speed^1Head: speed^2Power: speed^3Same impeller diameter
Range vs Approach
Range
- Hot minus cold water
- Set by heat load
Approach
- Cold water minus wet-bulb
- Set by tower size
Load-driven vs tower-driven
Power Cycles
- Carnot
- 1 - TL / TH
- Otto
- 1 - 1 / rk^(k-1)
- Brayton
- 1 - 1 / rp^((k-1)/k)
- Diesel
- Adds cutoff ratio term
- Dual cycle
- Constant volume plus pressure
- Rankine
- Turbine work / heat added
- Reheat
- Cuts turbine exhaust moisture
- Regeneration
- Extraction heats feedwater
- Otto versus Diesel
- Same rk, Otto higher
Ton of Refrigeration
One ton is 3.516 kilowatts
3.516 kW12,000 Btu/hr211 kJ/minRate, not quantity
Indicated vs Brake Power
Indicated
- From pressure-volume card
- Includes friction losses
Brake
- From dynamometer
- Delivered at shaft
Cylinder vs shaft output
Boilers + Steam
- Boiler efficiency
- Steam heat / fuel heat
- Factor of evaporation
- Heat absorbed / 2257 kJ/kg
- Equivalent evaporation
- Steam rate x FE
- Boiler horsepower
- 35,322 kJ/hr each
- Dulong HHV
- 33,820C + 144,212(H-O/8) + 9,304S
- Rated boiler HP
- Water-tube: 10 sq ft
- Excess air
- Above stoichiometric requirement
- Draft
- Pressure difference moving gas
Reheat vs Regeneration
Reheat
- Second turbine expansion
- Cuts exhaust moisture
Regeneration
- Extraction heats feedwater
- Raises cycle efficiency
Blade safety vs efficiency
Engines + Performance
- Indicated power
- From P-V indicator card
- Brake power
- From dynamometer torque
- Friction power
- Indicated minus brake
- Mechanical efficiency
- Brake / indicated power
- Brake thermal efficiency
- Brake power / fuel energy
- Bmep
- Brake work / displacement volume
- Heat rate
- Fuel energy / net output
- Overall plant efficiency
- Product of stage efficiencies
NPSHa vs NPSHr
NPSHa
- System supplies it
- Raise by lowering pump
NPSHr
- Pump demands it
- Fixed by manufacturer
Available must exceed required
Pumps, Fans, Compressors
- Water power
- rho g Q H
- Pump efficiency
- Water power / brake power
- Net head
- Gross head minus friction
- NPSHa
- Atmospheric minus vapor, static, friction
- Cavitation starts
- NPSHa below NPSHr
- Affinity: flow
- Varies with speed
- Affinity: head
- Varies with speed squared
- Affinity: power
- Varies with speed cubed
- Fan total pressure
- Static plus velocity pressure
- Ideal intercooler pressure
- Square root of P1 P2
Refrigeration + Air Conditioning
- 1 ton refrigeration
- 3.516 kW = 12,000 Btu/hr
- COP cooling
- Refrigerating effect / work
- COP heat pump
- COP cooling plus 1
- Latent heat of fusion
- 335 kJ/kg for water
- Specific heat, ice
- 2.093 kJ/kg-K
- Sensible heat factor
- Sensible / total heat
- Bypass factor
- Air leaving coil untreated
- Saturated air
- Dry-bulb = wet-bulb = dew-point
- Equal-friction duct method
- Same drop per length
- Comfort drivers
- Temperature, humidity, air motion
Plant + Safety Metrics
- Load factor
- Average load / peak load
- Capacity factor
- Average load / rated capacity
- Use factor
- Output / capacity x hours
- Demand factor
- Maximum demand / connected load
- Diversity factor
- Sum of demands / peak
- Injury frequency rate
- Injuries x 1,000,000 / man-hours
- Injury severity rate
- Days charged x 1,000,000 / man-hours
- Cooling tower range
- Hot minus cold water
- Cooling tower approach
- Cold water minus wet-bulb
MEEBES Item Split
Math 32, Chem 12, Thermo 6
Mathematics: 32 itemsAnalytic geometry: 12Economics block: 15Fluid mechanics: 4
Nominal vs Effective Rate
Nominal
- Stated annual rate
- Ignores compounding frequency
Effective
- True annual yield
- 12% monthly = 12.68%
Quoted versus actual
Economy Factor Picker
- Present to future→F/P factor
- Future to present→P/F factor
- Series to future→F/A factor
- Future to series→A/F sinking fund
- Series to present→P/A factor
- Present to series→A/P capital recovery
- Unequal service lives→Annual worth comparison
- Rates compound differently→Convert to effective
MEEBES Item Counts
- Mathematics
- 32 items24%
- Analytic Geometry
- 12 items8%
- Economics, Law, Ethics
- 15 items14%
- Chemistry
- 12 items8%
- Physics
- 10 items10%
- Strength of Materials
- 9 items14%
- Thermodynamics
- 6 items12%
- Fluid Mechanics
- 4 items10%
- Subject total
- 100 items, 35% weight
PME vs ME
PME
- Signs and seals plans
- 4 years practice
- Any plant size
ME
- Passes written MELE
- BSME, no experience
- Up to 2000 kW
Seals versus supervises
Economy Factors
- F/P
- (1 + i)^n
- P/F
- 1 / (1 + i)^n
- F/A
- Uniform series compound amount
- A/F
- Sinking fund factor
- P/A
- Series present worth
- A/P
- Capital recovery factor
- Effective rate
- (1 + r/m)^m - 1
- Continuous compounding
- e^(rn)
- Unequal lives rule
- Compare annual worth
Depreciation Methods
- Straight line
- (FC - SV) / n
- Sinking fund
- (FC - SV) x A/F
- Sum-of-years digits
- Accelerated, digit weights
- Declining balance
- Constant rate on book
- Double declining
- Rate = 2 / n
- Book value
- Cost minus accumulated depreciation
- Salvage in declining
- Not subtracted first
- Break-even point
- Fixed / (price - variable)
Strength of Materials
- Axial deformation
- P L / (A E)
- Hooke's law limit
- Valid below proportional limit
- Thermal deformation
- alpha L delta-T
- Thermal stress
- E alpha delta-T
- Poisson's ratio
- Lateral / axial strain
- Modulus of rigidity
- G = E / (2(1 + v))
- Maximum shear stress
- Half principal stress difference
- Torsional shear
- T r / J
Thermodynamics + Fluids
- Ideal gas law
- P V = m R T
- Isentropic relation
- P V^k = constant
- Isothermal work
- P1 V1 ln(V2/V1)
- First law, closed
- Q = delta-U + W
- Enthalpy
- h = u + P v
- Bernoulli head form
- Pressure + velocity + elevation
- Continuity
- A1 V1 = A2 V2
- Reynolds number
- rho V D / mu
- Laminar threshold
- Re below 2,000
- Darcy head loss
- f L V^2 / (2 g D)
Chemistry + Physics
- Avogadro's number
- 6.022 x 10^23 particles
- Molar volume, STP
- 22.4 L per mole
- Half-life decay
- N0 x 0.5^(t / half-life)
- Decay constant
- 0.693 / half-life
- Wave relation
- v = f lambda
- Speed of sound
- 331 + 0.6t m/s
- Decibel level
- 10 log(I / I0)
- Reference intensity
- 10^-12 W/m^2
- Sensible heat
- m c delta-T
- Ohm's law
- V = I R
ME Law + Ethics
- Governing law
- RA 8495, year 1998
- Three categories
- PME, ME, CPM
- PME experience
- 4 years after registration
- CPM experience
- 1 year plant practice
- Passing rule
- 70% average, none below 50%
- Third failure
- Wait one year
- Rating release
- Within 15 days
- Sealing threshold
- Piping at 70 kPa
- Penalty range
- P50,000 to P200,000 fine
- License renewal
- Every 3 years
- Law block items
- Law, Code, Ethics: 1 each
Common Traps
Power plant subject misread
Refrigeration and AC: 28 items ≠ Power plant design: 24
Thermo overweighted in MEEBES
Thermodynamics only 6 items ≠ Chemistry carries 12
Law block is small
ME Law: 1 item ≠ Whole law block: 4
Average cannot rescue
70% general average needed ≠ Any 49% still fails
Idler gear confusion
Changes rotation direction ≠ Never changes speed ratio
Weld sized on leg
Throat is 0.707 leg ≠ Leg overstates strength 41%
Radiation temperature units
Stefan-Boltzmann needs absolute ≠ Celsius gives wrong answer
Hoop versus longitudinal
Hoop is pD / 2t ≠ Longitudinal is pD / 4t
Calculator confiscated
Non-programmable, one unit ≠ FX-991ES models banned
Retake wait misread
No wait after first fail ≠ One year after third
Last Minute
- 1.Weights: 30 / 35 / 35 percent
- 2.100 items in each subject
- 3.Pass: 70% average, none below 50%
- 4.Three days, 8AM to 2PM
- 5.Non-programmable calculator, one unit
- 6.Machine Design alone: 81 items
- 7.Refrigeration plus AC: 28 items
- 8.Soderberg yield; Goodman ultimate
- 9.Euler K: 1.0, 0.5, 0.7, 2.0
- 10.Fillet weld throat = 0.707 leg
- 11.1 TR = 3.516 kW
- 12.Load factor peak; capacity rated
- 13.Affinity: flow, head squared, power cubed
- 14.Range is load; approach is tower
- 15.PME seals plans; ME supervises
- 16.Piping at 70 kPa needs PME
- 17.Third failure = one year wait
- 18.Idler changes direction, not ratio
Same family resources
Explore More Philippines PRC Engineering Exams
Continue into nearby exams from the same family. Each card keeps practice questions, study guides, flashcards, videos, and articles in one place.