Kuwait Heavy Machinery Theory key terms

The maximum load a machine or lifting accessory is designed to handle under stated conditions, as declared by the manufacturer, and never exceeded in service.

A manufacturer-supplied table or diagram showing permissible loads for a crane at given radii, boom lengths and configurations, including deductions for attachments and reeving.

The horizontal distance from the crane's slewing centre or tipping line to the centre of gravity of the suspended load, measured with the boom in the position used.

The turning effect produced by a load, calculated as load weight multiplied by its horizontal distance from the tipping point; the basis for stability calculations on mobile plant.

The ability of a machine to resist overturning, governed by the position of its combined centre of gravity relative to its tipping lines under static and dynamic conditions.

The line joining the outermost points of contact between a machine's wheels, tracks or outriggers and the ground, about which overturning would occur.

A retractable stabilising leg deployed from a mobile crane or excavator to widen the support base, which must be fully extended and set on firm ground before lifting.

The load per unit area transmitted through tyres, tracks or outrigger pads to the ground, which must not exceed the soil's capacity to avoid settlement or collapse.

Timber, mats or steel plates placed beneath outrigger floats or pads to spread load over a wider area and protect the ground surface from damage.

The maximum load that a sling, shackle, hook or other lifting accessory may safely carry, usually derived from its breaking strength divided by a specified factor of safety.

A test load applied to lifting equipment to verify its strength and integrity, normally greater than the rated capacity but below the load at which permanent deformation occurs.

The durable, legible tag, plate or colour code attached to lifting gear stating its safe working load and identification, without which the item must not be used.

A multiplier applied to a load to account for the increased tension in sling legs as the angle between them and the horizontal decreases; shallow angles sharply raise leg tension.

A lifting assembly of two legs connected to a common master link, whose capacity depends on the included angle between the legs and the symmetry of the load.

The large ring at the top of a multi-leg sling assembly to which all legs attach and which connects to the crane hook or shackle.

A U-shaped connector closed by a pin or bolt, used to join slings to loads or to each other, selected by working load limit and pin type.

A spring-loaded device fitted to a crane or sling hook that closes the throat opening to prevent slings and loads from slipping off accidentally.

Padding, sleeves or softeners placed between slings and sharp or abrasive load edges to prevent cutting, wear or damage to the sling fibres or wires.

A flat woven synthetic lifting strap, colour-coded by capacity, which must be inspected for cuts, burns, UV damage and label legibility before every use.

The point at which the whole weight of an object or machine may be considered to act; its position relative to the lifting point determines load balance.

The way a load's weight is shared among sling legs or across a machine's supports, which depends on the position of the centre of gravity and sling geometry.

A competent person appointed to direct vehicle and crane movements by agreed signals, keep pedestrians clear and act as the operator's eyes where visibility is restricted.

An agreed set of arm and hand movements used to communicate lifting, lowering, slewing and stopping instructions when direct voice or radio contact is unavailable.

A lifting operation where the operator cannot see the load or landing point and must rely entirely on signals from a competent signaller or radio communication.

The disciplined use of radio for lifting operations, including identifying the caller and receiver, repeating instructions, and using an agreed stop command.

A marked or barriered area around plant and lifting operations from which unauthorised people are kept out to prevent injury from falling loads or moving machinery.

The physical or procedural segregation of people from moving plant, using barriers, walkways, crossing points and site rules to prevent collisions.

The area covered by a machine's body or attachment as it turns, slews or travels, which must be kept clear of people, structures and services.

The circular area swept by the crane's superstructure, boom or excavator house when it rotates, requiring barricading to keep personnel clear.

A documented arrangement of access routes, one-way systems, parking, loading bays and speed limits that controls vehicle and plant movement on site.

A visual and functional check carried out by the operator before each shift, covering fluids, tyres, guards, alarms, brakes, lifting gear and safety devices.

A written or digital record listing the items to be checked each day and signed by the operator to confirm completion and note any defects found.

The formal process of recording and escalating any fault or damage found on plant or equipment so that it is assessed, repaired and signed off before further use.

Fitting a warning tag or lock to defective equipment to show it is out of service, preventing use until the fault is repaired and the tag removed by an authorised person.

A safety procedure that isolates energy sources such as engines, hydraulics or electricity and locks them off, with tags, before maintenance or repair work begins.

A detailed inspection of lifting equipment by a competent person at specified intervals, including proof load testing where required, recorded in a register.

A record listing all slings, shackles and lifting accessories with their identification numbers, capacities, examination dates and results.

The number of rope falls supporting the load in a reeved hoist system; more parts of line increase lifting capacity but reduce lifting speed.

The person with legal responsibility for the safety of a work activity, such as the employer, site owner or appointed supervisor, under applicable health and safety law.

A documented process of identifying hazards, evaluating who may be harmed and how, and recording control measures before work starts.

A formal written authorisation allowing a specific high-risk task to proceed under stated conditions, controls and time limits, signed by an authorised person.

A document describing the sequence of work, plant and equipment used, personnel responsibilities and control measures for a specific task.

A documented scheme for a lifting operation covering load weight, crane position, rigging, ground conditions, personnel roles and contingency arrangements.

A stocked container of absorbent materials, booms, gloves and disposal bags kept on site to contain and clean up fuel, oil or hydraulic fluid leaks.

A raised, impermeable wall or tray around fuel and oil storage that contains leaks and spillage, preventing contamination of soil and drainage systems.

Separating waste streams such as oily rags, used filters, scrap metal and general refuse into labelled containers so each is disposed of correctly.

Measures and devices on engines, such as filters and correct fuelling, that limit exhaust pollutants and must be maintained to remain effective.

The manufacturer's timetable specifying which grease points and oil reservoirs must be serviced, at what intervals and with which lubricant grade.

A small fitting on a bearing or pivot through which grease is injected with a grease gun during scheduled lubrication.

The oil that transmits force in a machine's hydraulic system; its level, cleanliness and correct grade are essential to safe operation and component life.

A mixture of water and antifreeze that removes heat from the engine; its level and concentration must be checked when the engine is cold.

The class of Kuwaiti driving licence that authorises operation of a particular vehicle or plant type, which must match the machine being driven.

The rules governing road use in Kuwait, including speed limits, lane discipline, signals, right of way and prohibitions on using hand-held phones while driving.