MILLWRIGHT LEVEL 3 CERTIFICATION
EVALUATION EXAMS 2026 SOLVED
QUESTIONS WITH FULL SOLUTION
◉ Pump Head.
Answer: The pressure a pump must overcome to move liquid
through a system, measured in psi, kPa, or bars (1 bar = 100 kPa),
and converted to a head measured in feet or meters.
◉ Factors that affect pump head.
Answer: Factors include static suction lift, pump centerline, vertical
distances from liquid supply to center line, surface of liquid in
discharge tank, pressure to overcome friction in the system, and
velocity head.
◉ Total Static Head.
Answer: Includes static suction and discharge head.
◉ Total Dynamic Head.
Answer: Describes a pump's head in the industry, calculated by
adding or subtracting dynamic suction lift, dynamic discharge head,
and frictional losses in pipes and fittings.
,◉ Vapor Binding.
Answer: Inadequate pressure on pump's suction side can lead to
vapor formation, blocking liquid flow and causing the pump to be
vapor-bound.
◉ Cavitation.
Answer: Occurs in a centrifugal pump when pressure drops, creating
vapor bubbles that collapse and erode the surface, leading to
vibration, noise, and impeller imbalance.
◉ Net Positive Suction Head (NPSH).
Answer: The suction pressure must exceed the liquid's vapor
pressure to prevent cavitation.
◉ Pump Capacity.
Answer: Determined by the volume of liquid delivered per unit of
time, such as US gallons per minute (USgpm) or liters per minute
(L/min).
◉ Volute Pumps.
Answer: Have a rotating impeller that discharges fluid into a spiral-
shaped volute cavity, converting velocity head into pressure.
◉ Diffuser Pumps.
,Answer: Have stationary, curved vanes that create multiple volutes,
redirecting liquid flow outward towards the discharge nozzle.
◉ Mixed Flow Pumps.
Answer: Combine radial and axial flow characteristics, developing
discharge head with centrifugal force and vanes lifting action, used
for low-head, high-capacity applications.
◉ Multi Staging.
Answer: Involves connecting several impellers in series in
centrifugal pumps to achieve higher discharge pressures than those
achieved by a single impeller.
◉ Peripheral Pumps.
Answer: Have the liquid entering at the periphery of the impeller,
energizing it and discharging it out again at its periphery.
◉ Split Casings.
Answer: Axially split casings are split along the axis of the shaft, with
suction and discharge nozzles usually in the lower half for easy
inspection.
◉ Barrel Casings.
, Answer: Eliminate the need for tight joints in split casings in high-
pressure centrifugal pumps, maintaining pressure without axial
joints.
◉ Pump Casing Materials.
Answer: Depends on the liquid that will be pumped.
◉ Pump casing materials.
Answer: The materials used in pump casings depend on the liquid
that will be pumped.
◉ Water, gasoline and other chemically neutral liquids.
Answer: Cast iron casings with bronze fittings.
◉ Acids.
Answer: Bronze, stainless steel, special stainless steel (e.g.,
Hastelloy), monel, nickel, rubber, ceramic.
◉ Alkalis.
Answer: Cast iron, Ni-resist, stainless steel, special stainless steel
(e.g., Hastelloy).
◉ Slurries (chemically neutral).
EVALUATION EXAMS 2026 SOLVED
QUESTIONS WITH FULL SOLUTION
◉ Pump Head.
Answer: The pressure a pump must overcome to move liquid
through a system, measured in psi, kPa, or bars (1 bar = 100 kPa),
and converted to a head measured in feet or meters.
◉ Factors that affect pump head.
Answer: Factors include static suction lift, pump centerline, vertical
distances from liquid supply to center line, surface of liquid in
discharge tank, pressure to overcome friction in the system, and
velocity head.
◉ Total Static Head.
Answer: Includes static suction and discharge head.
◉ Total Dynamic Head.
Answer: Describes a pump's head in the industry, calculated by
adding or subtracting dynamic suction lift, dynamic discharge head,
and frictional losses in pipes and fittings.
,◉ Vapor Binding.
Answer: Inadequate pressure on pump's suction side can lead to
vapor formation, blocking liquid flow and causing the pump to be
vapor-bound.
◉ Cavitation.
Answer: Occurs in a centrifugal pump when pressure drops, creating
vapor bubbles that collapse and erode the surface, leading to
vibration, noise, and impeller imbalance.
◉ Net Positive Suction Head (NPSH).
Answer: The suction pressure must exceed the liquid's vapor
pressure to prevent cavitation.
◉ Pump Capacity.
Answer: Determined by the volume of liquid delivered per unit of
time, such as US gallons per minute (USgpm) or liters per minute
(L/min).
◉ Volute Pumps.
Answer: Have a rotating impeller that discharges fluid into a spiral-
shaped volute cavity, converting velocity head into pressure.
◉ Diffuser Pumps.
,Answer: Have stationary, curved vanes that create multiple volutes,
redirecting liquid flow outward towards the discharge nozzle.
◉ Mixed Flow Pumps.
Answer: Combine radial and axial flow characteristics, developing
discharge head with centrifugal force and vanes lifting action, used
for low-head, high-capacity applications.
◉ Multi Staging.
Answer: Involves connecting several impellers in series in
centrifugal pumps to achieve higher discharge pressures than those
achieved by a single impeller.
◉ Peripheral Pumps.
Answer: Have the liquid entering at the periphery of the impeller,
energizing it and discharging it out again at its periphery.
◉ Split Casings.
Answer: Axially split casings are split along the axis of the shaft, with
suction and discharge nozzles usually in the lower half for easy
inspection.
◉ Barrel Casings.
, Answer: Eliminate the need for tight joints in split casings in high-
pressure centrifugal pumps, maintaining pressure without axial
joints.
◉ Pump Casing Materials.
Answer: Depends on the liquid that will be pumped.
◉ Pump casing materials.
Answer: The materials used in pump casings depend on the liquid
that will be pumped.
◉ Water, gasoline and other chemically neutral liquids.
Answer: Cast iron casings with bronze fittings.
◉ Acids.
Answer: Bronze, stainless steel, special stainless steel (e.g.,
Hastelloy), monel, nickel, rubber, ceramic.
◉ Alkalis.
Answer: Cast iron, Ni-resist, stainless steel, special stainless steel
(e.g., Hastelloy).
◉ Slurries (chemically neutral).
