Curemate 750 – Climatic Curing Cabinet

The Curemate 750 is an upright climatic curing chamber that holds cement and mortar specimens at a set temperature and relative humidity while they cure. It keeps that climate steady from casting until testing, which is what makes a strength result from those specimens worth comparing.

Comparison is the reason curing is controlled at all. A 28 day strength result only means something against the same test run in another laboratory if the specimens spent those 28 days in the same conditions, and a cabinet that drifts in temperature or loses humidity changes the strength the specimens reach.

In a cement laboratory the cabinet sits between the mortar mixers where the specimens are cast and the press where they are broken. Filled moulds go onto its shelves after casting and stay there under the conditions the test method sets.

With six shelves fitted, the Curemate 750 holds up to 24 moulds at a time. It is supplied with four shelves in plasticized steel as standard, and two more can be added when the laboratory needs the full capacity.

Each shelf measures 600 × 800 mm (23.6 × 31.5″), pulls out of the cabinet for loading and carries up to 40 kg (88 lbs). Steel moulds are heavy once filled, so it pays to check the weight of a loaded mould against the shelf rating before deciding how many go on each level.

The mould count decides how many casts can be curing at the same time, so it follows from the number of batches a week and the ages at which you break specimens.

Tell us how many moulds are in cure on a typical day through our quotation form, and we will size the shelf set to go with the cabinet.

The Curemate 750 holds any temperature from +15 °C to +30 °C to within ±1 °C, and relative humidity from 80% up to saturation at 100%. Both values are set on the digital controller, and the chamber works to bring the climate back whenever it moves away from the set point.

A common cement curing setting is 20.0 °C at 95.0% RH, well inside both ranges. The upper part of the humidity range matters most for curing, because specimens that dry at the surface lose part of the strength they would otherwise gain.

The ±1 °C band applies across the whole temperature range, so a set point near either end is held as closely as one in the middle. Programs that need curing colder or warmer than this range will find a cabinet with a wider span among our climatic curing chambers.

The controller shows temperature and relative humidity at all times with a resolution of 0.1, for example 20.0 °C and 95.0% RH. It also shows which phase the chamber is in: cooling, heating, ventilation or humidification.

The phase display is useful in daily work. A technician can see at a glance whether the chamber is cooling, heating or adding moisture, and whether a reading that moved after the door was opened is already being corrected.

The 0.1 resolution lets the operator compare the climate with a tolerance of ±1 °C with room to spare, and note the readings in the curing log at each inspection. That written record is what an auditor or a client asks for when a strength result is questioned, and it shows that the specimens cured in the conditions the method sets.

Humidity is produced automatically by vaporization, so the chamber adds moisture to the air on its own whenever relative humidity falls below the set point. The controller runs this as its humidification phase and shows it on the display while it is active.

Vaporization lets the cabinet reach saturation at the top of its 80% to 100% RH range, which covers the very humid air that cement curing calls for. In that climate the specimen surfaces stay damp, and the water in the mix stays available for the cement to hydrate.

Because the humidifier works automatically, the operator has no need to wet the specimens or spray the chamber by hand during the curing period. The ventilation phase moves the moist air inside the cabinet, which helps moulds on the upper and lower shelves cure in the same climate.

Cooling comes from an airtight refrigeration system with air condensation, and heating from a thermostatically controlled heating element with low thermal inertia. Both are needed because the room around the cabinet can be warmer or cooler than the curing set point, and it changes through the day.

Low thermal inertia means the element warms up and cools down quickly, so heat stops soon after the controller stops calling for it. That limits overshoot, the swing past the set point that a slower, heavier element would cause at the end of each heating cycle.

Air condensation means the refrigeration unit releases its heat into the room air, so no cooling water connection is involved. The airtight circuit keeps the refrigerant sealed in, which suits a cabinet that runs around the clock for the whole of a 28 day curing period.

The chamber spends its working life at high humidity, often close to saturation, so both the inner and the outer structure are made of AISI 304 stainless steel. Plain carbon steel would corrode in that climate, while AISI 304 stands up to constant moisture and to the alkaline residue that comes off fresh cement and mortar.

Stainless steel also keeps the chamber easy to clean. Spilled mortar and residue from the moulds wipe off the smooth walls and floor, so the inside stays in good condition through years of daily loading.

The outer skin in the same steel copes with wet hands, wet moulds and the cleaning that a curing area sees every day. The shelves are plasticized steel, which carries the weight of filled moulds while the coating protects the metal from the wet air.

The walls carry 60 mm of self-extinguishing polyurethane foam, made without CFCs. That layer separates the chamber climate from the room, so the refrigeration and heating work less to hold the set point when the laboratory warms up during the day or cools down overnight. Self-extinguishing foam stops burning once a flame is taken away.

The front service door closes on a magnetic sealing gasket, which keeps humid air in and room air out along the whole door frame. A tight seal matters at high humidity, since every leak lets moisture escape and makes the humidifier run longer.

The door also has a safety key closure, so the cabinet can be locked while specimens are curing. That protects a test series from being disturbed by an unplanned opening and keeps the specimens secure until they reach their test age.

The outer dimensions are 780 × 1,000 × 2,150 mm (30.7 × 39.4 × 84.6″), width by depth by height, and the cabinet weighs 185 kg (408 lbs). It stands upright with a single service door, which suits laboratories where floor area is the constraint rather than height.

Inside, the chamber measures 660 × 830 × 1,370 mm (26 × 32.7 × 53.9″). The difference between the inner and outer figures is the insulation and the machinery, so the outer size is the one to plan the room around, together with clear space in front for the door to open fully.

Check the ceiling and any doorway on the delivery route against the 2,150 mm height before the cabinet arrives. When a new cement laboratory is planned around it, our cement and concrete testing equipment covers the mixers, setting time and fineness apparatus that usually stand nearby.

Choose by the shape of the room first. The Curemate 750 is a tall, upright cabinet with a single service door and up to 24 moulds on six shelves, so it fits a laboratory with plenty of height but little free floor.

The Curemate 550 holds a comparable volume in a low, wide cabinet, and its top doubles as a work bench. It suits a room with a long free wall and a need for extra bench surface beside the curing area.

Then look at the curing temperatures your programs call for, and at how often the cabinet will be opened through the day. Laboratories that cure large series at one or two standard set points and want to keep floor area free usually find the upright Curemate 750 the easier fit.

The Curemate 750 runs on 220 V, 50 Hz, single phase, and draws 1,600 W. That one supply feeds the refrigeration, the heating element, the humidifier and the controller, so the cabinet needs a single power point of the right rating and nothing else from the building's electrical system.

The chamber runs continuously through a curing period, so it is worth putting it on a circuit that is not shared with heavy equipment such as presses or ovens. A tripped breaker elsewhere then does not interrupt the climate in the middle of a test series.

The refrigeration circuit uses R404a gas, which is free of CFCs, and the polyurethane insulation is CFC-free as well. Both points matter to laboratories that follow environmental purchasing rules or keep a register of the refrigerants in their equipment.