NCCCO Concrete Pump (CPO) key terms

Extendable stabilizer leg that transfers pump or boom weight into the ground away from the chassis, widening the support base and reducing load on any single point.

Load-spreading plate placed under an outrigger float to increase contact area and lower pressure on the supporting soil or slab.

Force per unit area that a pump, outrigger, or pad imposes on the soil or slab beneath it, calculated from the load and the effective contact area.

Layered timber or manufactured blocking used under pads or tracks to spread load, level the machine, or bridge soft spots in the supporting surface.

Hidden underground cavity such as a culvert, septic tank, basement, or utility trench that can collapse under pump or outrigger loading even when the surface looks solid.

Marking of buried gas, electric, water, sewer, and communications lines before setup, so outriggers, pads, and trucks are kept clear of potentially hazardous or collapsing structures.

Pre-job walk of the placement area to identify access routes, overhead obstructions, ground conditions, slope, traffic, and hazards that affect where the pump is set and how the boom is deployed.

Three-dimensional reach and clearance zone of the boom at all permitted positions, used to check for power lines, structures, and crane swing before and during pouring.

Required clearance in feet or meters kept between any part of the boom or line and energized power lines, established by the utility or the applicable electrical safety standard.

Designated worker who watches boom and hose movement, overhead lines, and personnel, and who signals the operator when the path is clear or when motion must stop.

Agreed gesture used between the operator and a signal person when radio communication fails or is impractical, established in a pre-job briefing before pumping begins.

Short meeting before pumping that covers the plan, roles, communication method, hazards, emergency stops, and exclusion zones so every crew member knows their responsibilities.

Area around the pump, hopper, and discharge end kept clear of unauthorized people because of pinch points, hose whip, and the risk of sudden line movement or failure.

Violent lashing motion of a flexible hose or end line when a blockage releases or a coupling fails, capable of striking and seriously injuring nearby workers.

Restriction in the delivery line caused by a dry slug, oversized aggregate, poor mix, or insufficient priming, signaled by rising pressure and reduced or stopped output.

Process of filling the pipeline with lubricating material, such as grout, slurry, or a sponge and water, before concrete is pumped so the first mix does not dry out and plug the line.

Separator, sponge, or wad pushed through the line to clean it or to separate materials; a dry slug can create a blockage if driven too fast or too far.

Instrument on the pump showing delivery-line pressure; a rapid rise or abnormally high reading is the primary early warning of a blockage or restriction.

Pressure-limiting device that opens to release hydraulic or line pressure before components or hoses are damaged, reducing the severity of a sudden failure.

Pressure-storage component in some hydraulic systems that holds pressurized fluid; it must be bled per manufacturer procedure before any service work to prevent sudden release.

Formal procedure for isolating energy sources, applying locks and tags, and verifying zero energy before maintenance, cleaning, or repair on the pump or delivery system.

Pre-shift check of fluid levels, hoses, couplings, safety devices, outriggers, boom pins, and wear parts, documented before the pump is placed in service.

Sacrificial metal plate in the hopper and S-tube area that takes abrasion from concrete flow and must be checked for thickness and replaced before it wears through.

Swing-tube valve that alternately connects each concrete cylinder to the delivery line, reversing with each stroke to provide continuous pumping.

Receiving bin at the pump that holds concrete for the cylinders and contains the agitator and valve assembly; it is a major pinch-point and entrapment hazard.

Rotating paddle shaft in the hopper that keeps concrete moving and feeding into the cylinders; it must be stopped and isolated before anyone reaches into the hopper.

Safety circuit that prevents boom or outrigger movement when outriggers are not properly extended, the boom is stowed, or another unsafe condition exists.

Multi-section articulated boom whose sections fold and unfold in a controlled sequence to reach the placement point without striking structures or lines.

Flexible hose at the boom tip used to place concrete precisely; it must be rated for the pump pressure and secured with a safety cable to prevent it from falling.

Secondary tether or restraint that keeps a hose, coupling, or attachment from falling to the ground if its primary connection fails.

Clamp or connector joining delivery-line sections; it must match the pipe rating, be properly gasketed, and be inspected for wear and secure locking.

Rigid and flexible piping that carries concrete from the pump to the placement point, supported to prevent sagging, movement, and excessive pressure at bends.

Measure of concrete consistency that affects how easily it pumps; mixes that are too stiff raise line pressure and blockage risk, while overly wet mixes segregate.

Separation of paste from aggregate during handling or pumping, producing rock pockets and blockages; controlled by mix design, slump, and steady pumping.

Cold-weather measures such as draining water lines, keeping water in the tank, and warming components so ice does not block lines or damage the pump.

Clearly marked control that immediately halts pump, boom, or agitator motion; its location and function must be covered in the pre-job briefing.