Vertical Reciprocating Conveyor Glossary
C LOAD PATTERN: Carriage configuration with load/unload access on one side of the carriage.
Z LOAD PATTERN: Carriage configuration with load/unload access on two opposite sides of the carriage.
90° LOAD PATTERN: Carriage configuration with load/unload access on two adjacent sides of the carriage.
BACKSTOP PANEL: Expanded-metal safety enclosure welded to the lift guide columns during installation to create an additional carriage side guard during mezzanine loading operations.
CDLR: Chain driven live roller; conveyor section mounted on the carriage to transfer load on/off VRC.
CANTILEVER: Both lift guide columns are on the backside of the carriage - used for 90º loading, overhead height or space restrictions.
CARRIAGE: The usable area of the lift where materials are loaded and conveyed up/down between levels.
CHAIN TENSIONER: This assembly uses a limit switch assembly to monitor chain tension and cut power to the motor if the chain becomes too tight or slack.
CHECK VALVE: Hydraulic valve that holds the carriage in place if the E-stop is pressed or power is lost.
GUIDE COLUMNS: The vertical members in which the carriage travels up and down.
COLUMN SPLICE: Guide columns are shipped in multiple pieces. Field welding required.
CONSTANT PRESSURE: Refers to a push button operation that requires the operator to maintain pressure on button until carriage reaches selected level.
DECK: The floor of the carriage or platform (smooth, tread plate) where materials are placed.
DECKLOCK: Carriage lock that automatically extends to prevent carriage free fall at critical upper levels. A safety device that extends under platform during loading or unloading carriage.
DIAGONAL DROP BAR: Load-defining steel bar and safety chain across operating end(s) of a carriage to help contain unstable loads.
DRIVE BASE: Gear reducer brake motor assembly that is mounted at the top of the lift guide columns on mechanical units.
DROP TEST: Demonstration of the safety cam operation. The carriage is loaded to rated capacity. Chains are slackened by supporting carriage in an elevated position. Support is then pulled out allowing the carriage to drop and confirm proper safety cam operation.
ENCLOSURES: Code-required safety fencing on all operating levels to protect workers against nip, shear and pinch points. (Can be expanded metal, block, drywall, etc.)
GENERAL ARRANGEMENT (GA) DRAWING: Approval drawings produced by PFlow, which shows our lift, gates and enclosure arrangements in plan and elevation views.
HEADER: The horizontal structure spanning the width of a carriage or gate.
HYDRAULIC POWER UNIT: The motor, pump, and reservoir assembly. (Most hydraulic power units come with the control panel attached and motor pump pre-wired to the control panel.)
INTERLOCK: An integral electro/mechanical device that prevents access gates or doors from opening when the carriage is not present and prevents the lift from operating if a gate door is open.
INTERMEDIATE STOP: Any access level between the lowest level and highest level that the lift will service.
KNOCKDOWN (KD) CARRIAGE: Carriage designed to ship in pieces. Field welding is required.
KEY LOCK CONTROL: A keyed push button station that prevents unauthorized use.
KICK PLATE: A solid steel toe barrier on the outermost edge of the inoperable sides of the carriage deck,
LIFT PRESENT LIGHT: Light on push button station which alerts the operator that the carriage has arrived at that level.
LOAD HEIGHT: Allowable vertical clearance on a carriage or through the gate. (7’ is standard)
LOAD TEST: Carriage is loaded to rated capacity and is raised and lowered to demonstrate lifting capability.
MOMENTARY CONTACT: Push button station that permits the operator to touch and release the desired mode while carriage travels to selected level and stops automatically.
PIT: A depression in the floor usually 1” deeper than the carriage profile. Allows the deck to position flush at floor level.
PNEUMATIC GATE OPERATOR: An automatic actuator which requires in-plant, clean, dry air. Can be operated by either pull cord or push button controls.
QUICK-CONNECT ELECTRICAL CABLING: Special cables are pre-mounted to the control panel and have screw-on connectors at the ends of the cables. Connectors are then attached to the pre-mounted ends on the interlocks and push-button stations. (Available on hydraulic models)
ROLL OFF PANEL: See Backstop Panel.
SAFETY CAMS: Spring-loaded, hardened steel cams attached to the lifting chain. Cam rotates and engages the guide columns if chain breaks, preventing the carriage from dropping more than a few inches.
SAFETY GATES: Expanded metal vertical, swing or slide interlocked access panels to load and unload carriage at each level.
SIDE GUARDS: A protective fixed enclosure on the outermost edge of the inoperable sides of the carriage welded to the deck to contain load. Can be rails, sheet steel, or expanded metal.
STRADDLE: Lifting guide columns are the midpoint of the carriage on each side which offers even distribution of weight on components.
T.O.R.: Abbreviation for "top of roller"; refers to roller height in conveyor systems.
UPRIGHTS: The structural portion of the carriage that houses the wheels that guide the carriage as it travels up and down in the lift guide columns.
VELOCITY FUSE: Device to restrict the flow of hydraulic fluid in the event of hose rupture.
VERTICAL RECIPROCATING CONVEYOR (VRC): VRCs move materials from one level to another. VRCs are not elevators and people cannot ride them. They have their own national code (ASME B20.1) and are specifically exempt from the national elevator code.
VERTICAL TRAVEL: Total distance carriage travels between all floor levels.
WHEELBLOCK: Assembly bolted to the uprights containing the wheels within the lift guide columns that guide the carriage during travel.