The group of equipment for cooling caramel include open narrow conveyor belts for pre-cooling the molded candy chain;
- open inertial conveyors for cooling the finished caramel and fruit drops;
- Closed bunk inertial conveyors;
- closed mesh conveyors type KLA
The equipment for the finishing of caramel outdoor varieties include:
- Dragee boilers for polishing and dusting of caramel;
- units for continuous polishing candy,
- established in mechanized production lines manufacturing caramel-glazed.
Devices for cooling caramel
Narrow belt conveyor. Conveyors are designed to pre-cool the caramel with the formation of a thin outer crust on it, which protects the products from deformation during further cooling, and sufficient cooling of the thin bridges between the products to facilitate their separation when entering the main cooling conveyor.
Fig. 50. Schematic diagram of the location of the cooling conveyor line production of caramel.
The narrow cooling conveyor simultaneously serves to transfer the molded products to the main cooling conveyor. These conveyors are usually manufactured by on-site factories.
The conveyor usually has a rubberized or cloth tape up to 100 mm wide; The length of the conveyor must be within 12 — 16 m. The master and slave drums and the tensioner of the conveyor are mounted on a light metal frame. The conveyor is closed box, which is supplied with cooling air. The drive is usually carried out from the drive of the caramel-forming machine, while the conveyor speed must be equal to the speed of movement of the caramel chain leaving the forming machine.
Single storey inertia conveyor.
The purpose of these conveyors is the final cooling of the caramel, transferred after molding by a narrow cooling conveyor. They are used mainly in semi-mechanized caramel production for cooling candy caramel.
Fig. 50 given schematic layout diagram of the cooling conveyor line production of caramel.
The chain-shaped molded hard candy is continuously transferred from the 1 caramel-forming machine to the narrow 2 cooling conveyor. The carrier conveyor belt is continuously blown with cooled air from the 3 air duct with an adjustable 4 damper. Next, the caramel chain enters the 5 swinging groove and breaks into individual caramels, which then fall on the 8 main inertial cooling conveyor, whose tray receives an oscillatory movement using an 9 eccentric-connecting rod mechanism with an oscillation amplitude from 5 to 30 mm
The conveyor is usually a tray of stainless steel or other metal tilted slightly to the side of the product, mounted on 11 inclined spring pillars (or roller bearings). Along the edges of the tray on its surface make holes for screening caramel chips. At the downstream end of the conveyor, an 12 control valve is installed. Open cooling conveyors are usually 10 — 15 m long and 600 — 800 mm wide.
The surface of the 8 inertial conveyor, through which the caramel moves in one layer, is continuously blown by cooling air supplied from the 7 air ducts with adjustable 6 and 10 dampers. The optimum temperature of the cooling air 16 — 18 ° C.
The total consumption of cooling air for both conveyors with this method of cooling varies from 6000 — 9000 to m3 / h.
The disadvantages of such conveyors are considerable length, crumbs sprayed in the shop, inefficient use of cooling air. Therefore, when creating production lines, more compact and productive closed cooling conveyors were developed.
Fig. 51. The two-storey cooling conveyor inertia SHT2-In.
The two-storey conveyor inertia SHT2-in closed.
Conveyor ШТ2-В is designed for cooling molded caramel in production lines of caramel production. The conveyor consists of two parts (fig. 51). In the upper part there are two trays made of sheet steel, to which cooled caramel is supplied, in the lower part - a drive with an electric motor, an eccentric shaft and hinged supports.
A chain-shaped caramel with jumpers (with temperature 65 — 70 ° С) is fed by a narrow belt conveyor to the swinging inclined groove 5, on which the jumpers are broken and the candy is evenly distributed over the surface of the 1 upper swing tray.
On this tray, located at an angle of ~ 1 °, thanks to its vibrations, the caramel moves downwards, then moves to the second vibrating tray 27 on which it is finally cooled.
Cooling air with temperature 16 — 18 ° C is fed to the 1 tray from above from the distribution slotted duct 3, and to the 2 tray — counterflow from the 6 nozzle.
The swinging trays rest on the 7 pivot bearings located at an angle 15 ° to the vertical. The trays are driven from the electric motor by means of two eccentrics (3 mounted on the shaft at an angle of 170 °, due to which the trays swing in opposite directions and their inertia forces partially balance each other.
The conveyor is located in a closed 4 chamber with service doors. The crumble formed during the passage of caramel is removed through the openings in the conveyor trays into special collections.
The cooling time of the caramel on the conveyor to 5 is min, the temperature of the outgoing caramel is 40 — 45 ° С.
Chilled caramel is continuously fed to the distribution conveyor, which feeds wrapping machines.
For the case of using a conveyor not in the production line, a special butterfly valve is provided for the possibility of unloading caramel into the workshop container at the exit from the second tray.
As the caramel moves along the chute of the cooling conveyor, it is cooled with air at a constant temperature / in.
The cooling time of each product (caramel) (sun) is determined by the formula
where Gи- mass of one product, kg; (II-13)
c is the average specific heat of the product, J / (kg-K) (defined as the arithmetic average of the initial and final specific heat of the product);
tн - the initial temperature of the caramel, ° C; tк - the final temperature of caramel, ° С;
α is the total heat transfer coefficient, W / (m X NUMX-K) (i = 2 – g * 23);
ƒк - surface area of a single product, м2;
∆t is the log-average temperature difference between caramel and air; calculated by the formula (1-30) at a constant air temperature tв = 15 ÷ 18 ° С.
The conveyor capacity (in kg / s) is determined from the conditions of convective heat exchange using the formula
where F - total surface area of cooling trays, m2;
ƒ — specific surface of caramel, м2 / kg;
g — specific surface load of the tray, kg of caramel on 1 м2;
φ is the filling factor of the tray (φ = 0,5 0,6).
Cooling conveyor pan length (in m) is dependent on the length and the average cooling rate% and
candy on a tray:
The average speed of caramel (in m / s) can be approximately determined from the performance:
Where B is the width of the conveyor, m (taken for structural reasons equal to 0,8 - 1 m);
h is the height of the layer of caramel, equal to the thickness of 1 pcs. caramel, m;
ρу—Conditional density of caramel, kg / m3, determined by the formula (П-8).
The unit for cooling caramel AOK. The unit is designed to cool the caramel after molding. The design of the unit is based on the principle of radiation-convective cooling of caramel during its movement on a mesh conveyor.
The structure of the unit (. Figure 52) includes: feeding vibroraspredelitel 1, 6 cooling chamber, outlet vibrolotok 9,
The feed vibrator is made up of an 2 shaker, which separates the caramel chain into separate links of several caramels, and an 3 tray that performs 60 swings in the horizontal plane in 1 min and stacks the caramel on the 4 vibration chute for sifting crumbs. From here, the caramel is sent to the 5 mesh conveyor for cooling.
The cooling chamber is a steel frame on which two 8 fans and two 7 air coolers are installed. They are located in the front of the camera.
Fig. 52. The unit for cooling caramel type KLA
Brine is fed to the unit with a constant temperature 10 — 12 ° С. A closed system of movement of cooled air with recirculation creates a steady mode of cooling, regardless of seasonal and meteorological conditions.
Above the upper working branch of the 5 mesh conveyor, air supply ducts with upper 11 nozzles are installed, and discharge ducts with lower 10 nozzles are located between the working and return branches. The lower boxes are connected to the fans side channels with filter nets. Heat from the caramel is removed by blowing air through the nozzle grids and absorbing heat from the outer surfaces of the nozzles painted with black paint (radiation heat exchange). The entire frame of the cooling chamber with fans and air coolers is covered with a frame of wooden frames with removable covers.
The discharge vibrolotok consists of a frame, the screen, and the eccentric drive.
The advantage of the AOK unit over the two-tier cooling conveyor is that the cooling time is halved due to the fact that the heat transfer from the caramel occurs here not only due to convective heat exchange, but also due to radiation emission (radiative heat transfer).
As shown by experimental data, the heat transfer coefficient in this case is much higher: with radiation heat removal α = 32 ÷ 40 W / (m2 • K), with convective a = 46 ~ 98, with radiation-convective a = 92 - g-116.
AOK units are produced with both brine and freon cooling. In the latter case, they are supplied with an individual refrigeration unit. The economic effect of the introduction of a single unit is 8 — 15 thousand rubles. in year. This unit gradually replaces the less efficient cooling conveyors ШТ2-В. The units are manufactured by the plant of experimental designs of the All-Union Scientific Research Institute of the Confectionery Industry.
Technical characteristics of the device to cool caramel
|Productivity, tons per shift||4-8||4-6|
|Temperature in the working chamber, ° С||8-15||0-3|
|The final temperature of the caramel, ° C||45-55||25-35|
|The duration of cooling, min||5-6||2-3|
|Airflow hour, m3 / h||15000-20000||8500|
|share, m3 / kg||15-30||8,5-10|
|consumption of cold|
|share, J / kg||126-168||75-84|
|Power demand in kW||8-9||6-7|
|Specific removal of products from the active cooling area, kg / (m2-h)||60-150||160-210|
Machines for polishing and dusting caramel
Draining boilers. Drazhirovochnye boilers are designed for glossing or sprinkling open varieties of caramel, as well as drazhirovanija - rolling and glossing pills.
Fig. 53. Coating pan DR-5M.
The DR-5М boiler (fig. 53) —periodic action, with manual loading and unloading, consists of the boiler /, the 5 bed and the drive mechanism.
The 1 boiler is spherical, made of sheet steel.
The bed is cast iron, consists of two parts. In the upper part there is a boiler and a main shaft 3 with a worm gear 4. The electric motor is mounted on a bracket. The movement is transmitted to the boiler from the electric motor through the clutch
and a pair of worm 4. To start and stop the boiler provides grip 2.
Above described, in the confectionery industry distributed a number of other types of coating pan. In particular, the widely adopted CVA-2 boilers (NDP).
In tab. 15 is a technical description of several varieties of coating boilers.
Technical characteristics of coating pan
|One-time boiler load, kg||100||60-80||100|
|Boiler speed, rev / min||20||20||20|
|The angle of inclination of the axis of the boiler, degrees||40||30||30|
|Electric motor power, kW||1||0,5||1,0|
To mechanize the loading of coating boilers, they are mounted to a switchgear, as shown in fig. 26. However, the unloading of the boilers here remained manual.
The Nagema Association (GDR) produces draining boilers of the type HL-86 with a rotary axis of rotation. When loading, the boiler axis is vertical, while working, it is tilted to the horizon at an angle 30 — 40 °, and when unloading, the boiler takes the vertical position with the hole down. The boiler has a diameter of 950 mm, a height of 500 mm, the diameter of its loading opening is equal to 600 mm. The installation takes the floor area 1000 X 1200 mm, the boiler rotates from the electric motor with the power 1,0 kW, and the rotation axis of its rotation is from the engine with the power 0,6 kW. The installation weight is 600 kg.
The machine for continuous polishing and dusting caramel.
The unit is designed for continuous open polishing varieties and caramel products to create a shiny protective layer or a rough surface consisting of sugar crystals (for obsypnyh varieties).
The unit UGK-3 (fig. 54) consists of an 7 drum, a dispenser for 4 sugar irrigation syrup, a dispenser for a wax / fat mixture (gloss) 5, for granulated sugar - 19, for talc - 16, 15 with a fan, a boot 3 vibrating channel and 77 unloading, 2 lifting mechanism, 18 scraper conveyor and control panel.
The drum - the main part of the unit - consists of a shell, two 9 bandages installed on it, and a 10 coronal gear. The drum rests on four roller bearings mounted on a frame. On the loading side, the removable 7 cone is attached, and on the discharge side, the 14 discharge cone is attached. The inner surface of the shell is covered with corrugated tin.
Inside the drum there are three adjustable partitions 5, which are sectors with an angle equal to 175 °. The first partition is installed at a distance 500 mm from the beginning of the loading cone 7, the second - at a distance 500 mm from the first, and the third - in the outlet of the discharge cone 14. Sealing rings are welded at the location of partitions.
Partitions are mounted on the axis of the drum, which is mounted on two racks. The axis is also a duct at the same time. In it, 300 holes are drilled with a diameter 7 mm in the length of 15 mm. To rotate the partitions around an axis, they have 6 and 13 handles, and the second partition rotates when the axis rotates.
The drive of the drum is carried out from the 12 electric motor by means of a V-belt transmission through the 11 spur gear. To fix the drum on roller bearings on the frame there are two hard rollers.
Dispensers for syrup of sugar and fat and wax mixtures are cam type pumps. The cam pump consists of a housing, a cam cover with a spring clipper, clipper cap, tube and gland. The pumps are installed in tanks of 4 and 5. Each tank is a tank consisting of a shell, bottoms, lids, two thermocouples for electrical, housing, rack, plug valve, plate for the installation of pumps, seals for pipes.
The cam-dosing pumps are driven by an electric motor through a V-belt transmission and a worm gear, the output shaft of which is pivotally connected to the shaft of the cam pump.
Fig. 54. The unit UGC-3 for continuous polishing caramel.
The supply of sugar syrup or wax-fat mixture from the dispensers into the drum is carried out through the tube with electrical heating. 4 and 5 dispensers are mounted on a common frame. Cam-type metering pumps are based on the principle of volumetric dosing.
Dosing of sugar is carried out by bucket elevator 19. The drive motor of the elevator carried through V-belt transmission and worm gear.
The 16 dispenser for feeding talc into the drum consists of a cylinder of a cylindrical shape and a conical bottom in which a turnstile is installed. Dosing is based on the principle of pneumatic feeding of talc in a sprayed form through a rotating turnstile and throwing it out of the pipe into the third section of the drum.
The unloading vibrolot - the 17 sifter - consists of a groove with sides and a net, a frame and two reflectors installed on the caramel inlet side of the drum. To transfer the processed caramel from the drum to the receiving bin for packaging, use the 18 scraper conveyor.
electrical unit is controlled from the control panel.
Caramel cooled to 40 — 45 ° C is continuously fed from the cooling conveyor via the 3 loading vibrating tray to the first section of the rotating drum, into which the sugar syrup 4 — 17% and temperature around 19 ° C is fed from the 100 dispenser.
When moving the caramel to the second section of the drum, a wax-and-fat mixture is applied to it from the 5 dispenser at the temperature 65 - 70 ° С.
When the caramel passes from the second section to the third to dry it, the inside of the drum is supplied with air heated by the heater up to the temperature 30 — 40 ° С, with relative humidity 60 — 65%. In the same section, 4 is produced — 5-minute processing of glossy caramel with talcum powder supplied by the 16 dispenser. Then the caramel is continuously discharged through the discharge tray 17.
When sprinkling caramel instead of gloss, granulated sugar is fed from the dispenser. The sprinkling process is carried out in two stages: caramel loading into the first section and watering it with sugar syrup; processing with granulated sugar at the end of the second stage and unloading. When sprinkling the first and second sections of the drum are combined into one by raising the first partition.
Technical characteristics of the machine for polishing and dusting caramel
|The performance of the unit, kg / h||1200|
|Productivity of the dispenser for watering syrup, g / min||250-450|
|for wax fat mixture, g / min||17-30|
|for talc, g / min||15-25|
|for granulated sugar, kg / min||1,5-2|
|Airflow, m3 / h||200-300|
|drum speed, rev / min||16-18|
|The drum angle, degrees||2,5-6|