LPSH-500 press. The main nodes of the LPS-500 screw macaroni press are a dosing device, a three-chamber kneading machine with a drive, a pressing housing with a drive, a pressing head for a round matrix with a die changing mechanism and a blower. All of the above nodes are mounted on a metal frame installed on four supports. In fig. 4.3 is a diagram of this press.
The press is equipped with a cutting mechanism, a water-ring vacuum pump, a vacuum gauge, a manometer for monitoring the process, a piping system with constant-level tanks for cold and hot water installed on 1,5 ... 2 m above the metering level, and an electrical system with a control panel to regulate the technological process. Its design is somewhat different from the design of the previous press and provides a smoother adjustment of the supply of ingredients to the kneading machine in a given ratio.
The dosing device is located above the upper chamber of the kneading machine and consists of a screw flour metering unit and a rotary water metering unit, combined on the same half-shaft.
The flour metering device has a 12 body, inside which is placed one end of a 11 hollow shaft with a length of 430 and a diameter of 60 mm. On the outer surface of the hollow shaft is installed single
Fig. 4.3. LPS-500 macaroni press scheme
13 screw auger with a diameter of 158 and a pitch of 70 mm. At the top of the flour metering unit, there is an 14 inlet for loading flour, at the bottom there is an 10 opening for flour exit.
Rotary dispenser is installed on the opposite side of the hollow tube. On the dispenser body, there are two 17 valves for supplying cold and hot water and an 16 impeller with a special profile that, when rotating, turns water into the slots of the hollow shaft. The amount of water entering the kneading machine is controlled by changing its level in the dispenser tank by turning the 79 handle connected to the shaft having the 18 slot and changing the rotational speed of the hollow shaft with a ratchet mechanism, which is the same design as in LPL-2M presses. The dosing unit is driven by the 75 chain transmission from the shaft of the kneader of the kneader; the rotational speed of the flour meter and rotary water metering screw is regulated within 0 ... 23 min-1.
The dough-mixing press machine consists of three chambers, the overall dimensions of which are as follows: the first one 1400x206x293 mm, the second and third 1400x328x424 mm. The first kneading chamber 8 is located above the second 44 and the third 40 and is closed on top with a 9 lattice cover with a lock. In this chamber, the dough is kneaded using 7 kneading blades mounted on an 6 kneading shaft. Through the 5 window in the side wall of the chamber, the dough is sent to the 4 vacuum shutter, which provides the necessary residual air pressure when passing the dough to the second and third
The vacuum shutter 4 has a rotary feeder 3 with two pockets with a volume of 750 cm3. The rotor is driven from the shaft of the first chamber through a gear. Rotational speed of the rotor of the vacuum gate 22 min-1
The second and third chambers are interconnected downstream by the 36 reloading window. Inside the chambers, as well as in the first one, there are 39 kneading shafts with blades and 38 fingers mounted on them in a certain sequence.
37 covers of both cameras are made of transparent organic glass, which makes it possible to observe the process. Eccentric clips 35 are installed for sealing the covers, the covers are also interlocked with the drive. Kneading chambers are made of sheet stainless steel 1 mm thick with a polished surface in contact with the product.
The drive of all three shafts of the kneading chambers is carried out from the 21 electric motor through a V-belt drive, gearbox and chain transmission system. Shaft speed of the first camera 75 min “1, shafts of the second and third chambers - 60 min-1. The drive is disconnected from the kneading shafts by means of a cam clutch.
The steam-air mixture formed during the dough kneading in the second 44 and the third 40 chambers is pumped out via a special 1 filter using a water ring vacuum pump BBH-1,5. The filter is installed in the end wall of the 44 chamber at the entrance window and consists of a cylindrical 46 body and two 47 filtering surfaces located inside the body. One surface is made of corrugated metal mesh, the other - from fabric. The first surface provides a rough cleaning of the vapor-air mixture from small crumbs of dough, the second - from flour particles. The filter housing has an 45 nozzle with a flange for connecting the filter to the trough housing, an 2 vacuum gauge nozzle for installing the 48 gauge, and an XNUMX nozzle for connecting the pipeline to the vacuum pump.
The pressing body is made of solid pipe Art. 20 length 1989 and diameter 166 mm, at the ends of which are installed the flanges 24 and 43 for mounting the pressing head and the reduction screw of the pressing auger. In the zone of maximum pressure of the pressing body (closer to the head) there is a cooling jacket 34, made in the form of a cylinder with a diameter of 230 mm. In the opposite zone of the pressing case there is an 41 window with 210 x 100 mm dimensions for entering the dough from the third kneader of the kneading machine. A single-thread 42 auger is installed inside the pressure housing.
The 25 pressing head is dome-shaped for a single circular die with a diameter of 350 mm. One end of the head is attached to the flange 24 of the pressing body, the other is closed with the 22 stopper. An 23 pressure gauge is attached to the cylindrical part of the head. The head is equipped with a mechanism for changing the matrix, the cutting mechanism
The matrix changer consists of a horizontal 30 rail for mounting and receiving dies, an 33 electric motor, a 32 worm gearbox and two 31 traction screws connected to the 29 crosshead. The magnitude of the traverse and the centering of the installed matrix is regulated by two limit switches. The activation of the matrix changing mechanism is blocked with the position of the cutting knives relative to the lower plane of the matrix: only when the blades are lowered down the required distance, the matrix changing mechanism electric motor can be turned on. The speed of the traverse when the ejection of the matrix
The piping system consists of four lines: for cold and hot water, its drain and vacuum drive.
Cold water is fed to the dosing unit for kneading dough and into the jacket of the pressing housing to cool the dough, hot water to the dosing unit for kneading dough. Excess unused water comes from the dispenser, as well as water from the jacket of the pressing body.
The work of the press as follows. Flour is fed into the flour metering unit, and hot and cold water is fed into the metering unit for water from tanks of a constant level. The temperature of the water entering the dough is controlled at the entrance to the kneader and is controlled by two valves on the dispenser manually by changing the ratio of cold and hot water. The temperature of the water entering the kneading machine is 55 ... 65 ° C, the water consumption for the dough kneading is 130 l / h, and for cooling the pressing unit 150 l / h.
The dough is kneaded in a three-chamber kneading machine. In the first chamber, intensive pre-kneading of the dough takes place for 6 ... 8 minutes and feeds it through the vacuum seal into the second and third chambers, which operate under vacuum. Residual air pressure during evacuation 20 ... 30 kPa. The total duration of the kneading process is about 20 minutes, during which time the necessary dough is achieved until a loose, uniform color is obtained, without traces of fine-grained mass with a size of a lump in diameter 2 ... 6 mm.
From the last chamber, the dough enters the screw chamber, from where it is fed by a screw into the pressing head and then molded through the die. It should be noted that two speeds of rotation of the pressing screw (17,5 and 23,5 min-1) allow you to change its performance depending on the range of manufactured products.
The pressure during the molding test on presses of this design is 9..12 MPa.
In order to preserve the quality of pasta and clean the forming dies in production, it is recommended to replace the pasta dies in the following order during the day:
Install the 28 steel ring with rubber seal into the mechanism housing.
install the 27 matrix into the clip and impose a 26 safety grid on it;
by turning on the reversible motor 33 of the mechanism, take the 29 yoke from the body to the extreme right position;
set the clip with the matrix on the table for feeding the dies and include the reverse rotation of the motor shaft; when moving the yoke, the yoke with the matrix takes up a working position.
LPSH-1000 Press. The press consists of the following main components: a dosing device, a centrifugal muffler, a two-chamber kneading machine, two pressing bodies and a tube. All press assembly units are installed on the service platform at a height of 3390 mm from the floor. In fig. 4.4 is a diagram of the LPS-1000 pasta press.
The press is equipped with two rectangular dies, a water ring vacuum pump with a special filter, a piping system and electrical accessories with a control panel. Monitoring the progress of the process is carried out using ammeters, vacuum gauges and pressure gauges.
The dosing device (see fig. 4.4) is made in the form of two rotary-type metering devices for flour and water, each of which is equipped with a drive consisting of an electric motor and a worm gearbox. The 2 flour dosing unit is a housing with two openings for 4 and 1 nozzles in the upper and lower portions, through which the flour enters and leaves. Inside the case is a four-pocket rotor 3 special profile.
The water dispenser is placed parallel to the flour dispenser and is a rectangular 5 body with a transparent 7 cylindrical tube installed on it. In the upper and lower parts of its fortified sensors 6, limiting the upper and lower levels of incoming water. With the help of a four-pocket rotary feeder 10, water is directed through the material of the conduit to the 11 centrifugal mucous humidifier. Regulation of the amount of incoming water in the dough kneading is carried out using the 8 valve installed on the material pipeline.
Fig. 4.4. LPS-1000 macaroni press scheme
The design of the dosing device provides the necessary sealing in the system when the components enter the kneading machine of the press, which makes it possible to knead the dough at a residual air pressure of at least 7 ... 9 MPa.
The 11 centrifugal mucooler, mounted above the top chamber of the 20 kneading machine, is a cylindrical tube of length 750 mm, having two connecting pipes 7 and 12 at opposite ends. Inside the pipe there is a single-thread 9 auger, one end of which is connected with an electric motor shaft using a special coupling to ensure that the auger rotates at a frequency of 900 min-1. Such a rotational speed of the screw allows you to mix components in a short period of time.
The dough mixing press machine has two chambers. The upper 20 chamber with a length of 1700 and a width of 800 mm is made of stainless steel sheet. Inside the camera, two 17 and 19 shafts are installed in parallel with 18 kneading blades fixed on it. Rotation of shafts with frequency 42 min-1 It is carried out from an individual drive, including an electric motor with V-belt transmission and a system of spur gears. The drive unit provides a lock to turn off the kneading shafts during their operation. On top, the chamber is closed with a 13 three-section pivot cover made of organic glass, which provides the necessary sealing inside the chamber and at the same time allows visual monitoring of the dough kneading process. In one of the end walls of the chamber there is a through hole connected by an 22 nozzle with an opening in the second lower chamber. This chamber is located perpendicular to the first one and is also closed by a two-piece pivoting 21 cover made of organic glass. The 16 pipe connected to the 14 filter is fastened to the end wall of the second chamber, through which the vapor-air mixture that is formed during the dough kneading is pumped out with a vacuum pump. 15 pressure gauges are installed on the filter housing to visually monitor the evacuation of the dough. Inside the chamber, an 23 shaft with blades, which are fixed symmetrically and at a certain angle, is installed, which makes it possible to evenly distribute incoming dough into two oppositely directed flows from the center to the holes in the pressing bodies.
Rotation of the kneading shaft of the second chamber with a frequency of 62 min-1 It is carried out from the electric motor with klinoremenny transfer and a one-stage cylindrical reducer.
Two pressing bodies are installed under the second chamber on opposite sides and perpendicular to the axis of the kneading shaft. At the junction points of the chamber and the press housings there are through holes 24 for entering test flows. The pressing body is a cylindrical tube composed in series of two sections 25 and 27 of length 810 and 1170, respectively, mm. The sections have two flanges at the ends: two for fastening the sections between themselves and two extreme ones for fastening the gearbox housing of the pressing device and the tube. The second section of the pressing housing is equipped with a water jacket 28, which is a cylinder with a diameter of 220 mm with two nozzles for supplying and draining water that cools the outer surface of the pressing housing in the zone of greatest pressure. The axially located 31 grooves are located along its inner surface along the entire length of the pressing body, which prevent the dough from turning against the internal walls of the body when the screw is rotating. A single-threaded 26 screw with a length of 1955, diameter 140 mm, with a pitch of screw 90 mm is installed inside the case; a three-way attachment 29 is fixed at the end of the screw, ensuring uniform flow of the test flow through the channel section.
The rotation of each screw with a frequency of 21,5 and 31,5 min'1 (depending on the produced range) is carried out from two individual drives, including an electric motor with a V-belt drive and a two-stage helical gearbox.
The 41 tube is a welded structure consisting of an 37 pipe with a 130 diameter of mm, two 38 connecting pipes with a diameter of 148 mm, an 35 manifold and a 39 die. The collector consists of 20 bronze bushings with an internal diameter of 22 mm, designed to evenly distribute the test flow along the length of the dies. The 36 oil bath with 3,2 kW electric heaters for short-term heating of the dough during the press start-up period and the 40 fuse operated at 16 MPa test pressure are built into the body of the tube. Visual control of the molding pressure is carried out using 30 gauges embedded in the connecting pipes.
Two rectangular matrices up to 955 mm long are installed end-to-end using a matrix holder, which is equipped with a mechanism for changing them. The mechanism is driven by an electric motor and two worm gearboxes fixed on both sides
Replacing the dies is done by pushing them out with the 32 rail. To this end, the new 34 matrix is installed at one end on the supporting planes of the 39 matrix holder in the end of the matrix, which needs to be replaced, the other end of the matrix abuts the 32 rail. After that, the motor is turned on, and the two 42 gears, when rotated, communicate a forward movement to the two 33 screws, which move the rail fastened with them. At the same time, the set matrix moves both matrices that are in the matrix holder, pushes the first 43 out of the chamber and is installed on the second one. Replacing the second matrix is similar.