Series 300: Mechanical Systems

Course 305: Pumps

Covers typical applications of various types of pumps. Describes factors affecting pump selection. Explains operating principles of centrifugal, propeller, and turbine, rotary, reciprocating, and metering pumps. Includes special-purpose pumps, diaphragm pumps, and others designed to handle corrosive and abrasive substances. Covers pump maintenance, packing gland, seal, and bearing replacement.

Lesson 1 - Pump Development and Application

Topics:

Development of pumps; Pumping systems; Water, chemical, waste, high-viscosity, and solids pumping systems

Learning Objectives:

• Describe dead-end and recirculating hot water distribution systems.
• List several special considerations involved in chemical pumping systems.
• Define the term viscosity and give examples of high-viscosity materials.
• Tell the effects of heat on the pumping of high-viscosity materials.
• List some special problems involved in the pumping of solids.

Lesson 2 - Basic Pump Hydraulics

Topics:

Terminology; Calculating total head, horsepower, and available vs required NPSH; Pump performance; Head capacity; Efficiency; Horsepower curves; Pump selection

Learning Objectives:

• Describe suction head and suction lift pumping conditions.
• Tell what three elements make up total dynamic head.
• Define static suction head.
• Contrast liquid, brake, and electrical horsepower.
• Tell what useful information can be gained from pump curves.

Lesson 3 - End-Suction Centrifugal Pumps

Topics:

Operation; Part definitions; Casing materials; End-suction casing configurations; Impeller types; Wearing rings; Shafts, bearings, and sleeves

Learning Objectives:

• Describe the function of the following: pump casing, shaft, impeller, wearing rings, and stuffing box.
• Contrast frame-mounted and close-coupled end-suction pumps.
• Give characteristics of fluids pumped with open, semi-open, and closed impellers.
• Name an advantage and a disadvantage each for stainless steel and brass shaft sleeves.

Lesson 4 - Propeller and Turbine Pumps

Topics:

Line-shaft, can, and submersible turbines; Flow patterns; Axial- and mixed-flow propeller pumps; Turbine pump construction and applications

Learning Objectives:

• Explain the construction of a line-shaft turbine pump.
• Name the two types of flow possible in a propeller pump.
• Tell the function of diffuser vanes in an axial-flow propeller pump.
• Define electrochemical corrosion and state its cause.
• Describe fluids that can be pumped by a regenerative turbine pump.

Lesson 5 - Rotary Pumps

Topics:

External-gear, internal-gear, lobe, screw, vane, rotary piston, and flexible-member pumps; Rotary pump installation

Learning Objectives:

• Describe the fluids that can be pumped by a rotary pump.
• Explain the operation of external- and internal-gear pumps.
• Describe the parts and construction of a lobe pump.
• Compare and contrast timed and untimed screw pumps.
• Tell why sealed bearings might be used in a vane pump.

Lesson 6 - Reciprocating Pumps

Topics:

Reciprocating pump applications, parts, classification, and operation; Horizontal and vertical plunger pumps; Air-driven pump operation

Learning Objectives:

• Name the parts that make up the power end of a reciprocating pump and describe their operation.
• Define the terms single-acting pump and double-acting pump.
• Compare simplex and duplex pumps.
• Explain how the pumped fluid lubricates a reciprocating pump.
• Calculate the discharge pressure of an air-driven pump when given the piston ration and motor air supply.

Lesson 7 - Metering Pumps

Topics:

Uses and classes of metering pumps; Plunger, piston, diaphragm, air-operated, and rotary metering pumps

Learning Objectives:

• Tell what kinds of pumps are used for metering applications.
• Describe metering pump lubrication techniques.
• Name the parts of a diagram metering pump and state the function of each.
• Explain the operation of a diaphragm metering pump.

Lesson 8 - Special-Purpose Pumps

Topics:

Handling difficult materials; Chemical, magnetic-drive, canned-motor, slurry, pulp-handling, trash, sewage, diaphragm, and vortex pumps

Learning Objectives:

• Describe the operation of a flexible-tube pump.
• Give an application for a progressing-cavity pump.
• Name one disadvantage of a seal-less magnetic-drive pump.
• Explain how to prepare a new centrifugal pump for operation.
• Tell which parts of a reciprocating slurry pump require the most maintenance.

Lesson 9 - Packings and Seals

Topics:

Sealing requirements; Stuffing boxes; Packing materials and recommendations; Installing packing; Mechanical, cartridge, balanced, and special seals

Learning Objectives:

• Tell why slight leakage through shaft seals is necessary.
• Name the type of stuffing box required for pumps operating under suction lift conditions.
• Give a typical application each for cotton, Teflon", and aluminum packing.
• Describe the procedure involved in replacing pump packing.
• Describe a packingless seal.

Lesson 10 - Pump Maintenance

Topics:

Pump bearings, lubrication, and seals; Pump installation and maintenance; Centrifugal, turbine, rotary, and reciprocating pump maintenance

Learning Objectives:

• Name three types of antifriction bearings.
• Name three factors to consider when preparing pump lubrication schedules.
• Describe a typical application for each of the following bearing seals: felt, leather, synthetic.
• Tell the two major maintenance problems encountered in rotary pumps.
• Explain how to identify worn piston rings in a reciprocating pump.