Maintenance technicians have numerous resources at their disposal to obtain repair instructions, replacement parts, and other resources that can contribute to safe, successful, and timely repairs.

Manufacture and Vendor Parts and Repair Resources

• Owner’s Manual- General customer orientation of equipment or component. Often contains safety precautions, operating instructions, basic troubleshooting and warranty information.
• Technical/Service Manual- Professional field technician repair reference. Contains complete troubleshooting instructions, schematics, and technical information related to the manufacturer.
• Vendor- Store or source where part might be obtained. Many vendors carry items from multiple manufactures, however, many manufactures may act as sole distributors for their own items.
• Catalog/Internet- Manufacturer or vendor itemization of available parts, description, and price.

Part Types

• Original Equipment Manufacturer (OEM)- manufactures products or components that are purchased by a company and retailed under that purchasing company’s brand name.
• Replacement (aftermarket)- Item made to perform the same function as original part, not manufactured by original equipment manufacturer.
• Universal- part made by a manufacturer that may replace similar parts on multiple manufacturers’ items or models of equipment.

Procurement

In many commercial settings, the technician is required to provide a purchase order (PO) to a vendor in order to obtain the necessary items to perform the service.

Requisition- The service technician must submit a request (requisition) to their employer or business office for the purchase of the required item(s). The requisition most often requires an accurate description of the item(s), price, part number, quantity, vendor, and vendor contact information.

Purchase Order- Once the technician has submitted the requisition for materials, the business office will generate a purchase order. This is an agreement between the purchaser and vendor for placing the purchase on a payment account. The business office will, in most all cases, issue a purchase limit or specified amount to be attached to the order based on previously quoted prices from the vendor.

Ordering Parts & Materials

When creating requisitions or ordering parts, equipment, and building materials from vendors, be specific. If any of the data on a replacement part does not match the original manufacturer’s requirements, the part/s may not provide adequate service for the application and could potentially damage other components of equipment and machinery. Manufacturers’ information is often available on the manufacturer’s tag or nameplate found on equipment, motors, pumps, propellers, blower motors, and other components. This information can be key to identifying and finding parts that are specific to an individual piece of equipment. Technical manuals provide more in-depth information, can be helpful in identifying specific parts and repair procedures, but do not always offer a way to obtain parts for repairs. Remember that manufacturers and parts vendors do not stock repair items forever. After production runs of various items end, the parts resource no longer carries specific parts and the item being repaired becomes obsolete or beyond economic repair (a similar item can be purchased at a cost that is cheaper than repairing the broken one).

Some of the most important things that can help a technician find the parts they need for repairs can be found on equipment nameplates or tags, or even on individual equipment parts and components include:

• Brand/Manufacturer- Maker or registered trademark holder
• Serial Number- Unique to the individual piece of equipment, often associated with ownership
• Model- Model numbers can signify a difference in power, size, accessories, or a wide variety of other options found in the terminology in this chapter
• Part number- Specific to the part, can often be cross-referenced to replacement and universal parts numbers
• Capacity or Rating
  • Horsepower- Associated with gas and electric motors and appliances
  • Torque/Ft. Lbs.- Amount of output force
  • Speed- RPM/ Variable/Fixed; Tool, motors, saw blades
  • Voltage- Alternating or direct current requirement
  • Ohms/ Impedance- resistance
  • Amps- Maximum and minimum or operational current
  • Wattage- Power capacity of electric appliances
  • Microfarad/Picofarad- Capacitors
  • British Thermal Units (BTUs)/Tons- Heating, air conditioning and refrigeration equipment
  • Weight- Lift or support limits
  • Phase- Electrical equipment; single or three phase
  • Cycle/Stroke- Gas motors
• Descriptive Terms
  • Gauge- Thickness of sheet metal, wiring conductors
  • Swing- Door and window direction of travel as they open
  • Pane- thickness of glass
  • Temper- hardened such as steel or glass
  • Finish- metal finishes, paints, stains,
  • Sheen- gloss, semi-gloss, matte, etc.
  • Rotation- clockwise/counterclockwise; fan and saw blades, threaded fasteners
  • Coarse/Fine- Screws, sandpaper, and other textured items

Quantities

Specific amounts, quantities, weights and sizes are always necessary for ordering parts and materials:

• Length/Width/ Height/Thickness- anything with proportional size
• Diameter/ Circumference/ Radius/Inside or Outside Diameter (I.D., O.D.)- tubing, plumbing, fan blades, motor shaft sizes, filters, etc.
• Schedule- PVC & ABS pipe wall thickness
• Area- square ft. square mile sheet goods, land (acre)
• Board Foot- lumber, 144 cubic inches or 12″ x 12″ x 1″
• Gross- Twelve dozen (144)
• Bag- contains a marked weight or item quantity
• Bundle- contains a marked weight or item quantity
• Ply- amount of layers an item has. Tires, plywood, paper products
• Roll- Paper products, asphalt roofing, plastic sheet goods, cloth and textile materials
• Unit- lumber, liquids, cased materials. Can imply a single item or a specific amount packaged for bulk purchase.
• Yard/Cu. Ft. /Sq. Yd.- concrete, fill, fertilizer
• Per inch/ foot/yd./etc.- lumber, wire, chain

Weights & Measures

Liquid Measures- pint, quart, gallon, liter, etc.
Dry Measures- gram, ounce, pound, ton, etc.

Standardized Measurement

Metric: European decimal equivalency; centimeters, millimeters, meters
SAE (Society of Automotive Engineers): American standard, fractional
Threads per inch (TPI): Bolts, nuts, and other fasteners
National Pipe Thread (NPT): tapered thread for plumbing applications