After repairing the concrete mixer and eliminating the malfunctions that have arisen in one or another part of it (and preferably immediately after purchasing the equipment), you should try to use the device in the future so that there are no more similar or any other problems.
If you try to follow all these not very complicated rules, then the concrete mixer will last for quite a long time and you won’t have to think about its repair throughout the entire period of operation.
If the device fails, then even someone who is not a great specialist in the field of construction can quickly repair concrete mixers with their own hands. It is enough just to determine which element has become unusable and replace it with a new one.
VIDEO
Repair of a concrete mixer is an important issue that sooner or later arises before every builder or owner of this tool. Unfortunately, breakdowns of concrete mixers are a common phenomenon, and there are a lot of reasons for this. Firstly, huge loads are placed on this device. Secondly, often the owners themselves do not pay proper attention to the tool, they operate and store it incorrectly. It is also fraught with negative consequences, which often require repair work. Before you get down to business on your own, you need to study all the information, stock up on the necessary tools.
You can repair a concrete mixer with your own hands only if you have experience in such work. Have you ever had to fix home appliances? Did you bring a car or a moped back to life? Then feel free to start repairing the concrete mixer. If you have never done this before, do not know how to hold a screwdriver in your hands and do not have at least an elementary set of tools at home, it is better to turn to professionals for help. Otherwise, there is a risk of completely losing your concrete mixer.
To repair the unit yourself, you will need a list of tools (of course, depending on the breakdown, the set may change). Among the main ones are pullers (three-arm and for bearings), a vice, pliers, a hammer, of course - screwdrivers, a chisel. Also, you can not do without a set of keys - gas, wrench, adjustable. Prepare the knife, tester and caliper in advance.
There are many reasons why you might need a concrete mixer repair. It happens:
when the unit loads more than the established norms;
the drum is not cleaned in time (this must be done after each use);
the tool is stored incorrectly and in improper conditions.
A special place is occupied by the repair of consumables - belts, drive gears, shutdown buttons.
Wear of parts, improper storage and operation are the most common causes of breakdowns in concrete mixers. But the replacement of thrust bearings and gear rims occurs much less frequently, all because their service life is much longer than the above parts.
Consider the main causes of breakdowns of the main parts of the concrete mixer.
Gears. As a rule, a quick breakdown indicates improper operation. Many owners consider it necessary to periodically lubricate the rims and gears, supposedly this reduces the load on the motor. And completely wrong! In this case, the load only increases. When working, cement / sand clings to the teeth, this increases friction and quickly abrades the metal.
Reducer. It wears out quickly due to poor cooling, overload. In this case, the part remains only to be replaced. There is even a chance that you will have to change the entire assembly.
Toothed crown. It is subject to significant mechanical stress. The material of this part is plastic or cast iron. More often, cast-iron parts come into disrepair (this is due to the low quality of the casting). Therefore, it is better to initially install a plastic crown.
Shutdown buttons. Often the cause of the breakdown lies precisely in them. This is expressed as follows: by pressing the button, the unit (motor) allegedly starts to start, but after a couple of minutes it stops working, stopping. In this case, it is important to replace the button with another one, the main condition is that it must have the appropriate number of contacts.
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Buttons in concrete mixers are magnetic actuators, not just an on/off design. This ensures the safety of operation, because if the power is suddenly turned off, the machine will stop, and when turned on, it will not start unexpectedly, thereby harming someone.
If the button has become unusable, slowly remove the casing (by unscrewing the screws that hold it), the button itself. Inspect the part, if necessary, clean the contacts. Also disassemble the button, cleaning it inside.
Sometimes it may happen that the motor works, but the tank does not (no rotation occurs). In this case, the cause may be in the belts. Remove the protective cover of the drive and assess the situation. Most often, the strap just slips off - in this case, you need to put it back in place. Sometimes, even if the belt is intact and not broken, it may not be suitable for further use. So, you can not do without buying a new one. To install it, loosen the bolts that attach the motor (there are two of them), install the belt. Start with a small pulley (near the motor), gradually moving to a large one. It is advisable to use someone's help - it is very difficult to cope on your own, because you need to delay the engine and immediately tighten the bolts. Actions happen at the same time.
Before you replace the gear and crowns, you need to try to rehabilitate them - lubricate them well with lithol. Turn the bowl upside down. Turn on the concrete mixer and spread the crowns with a spatula.
If the gear slips over the teeth of the crown, it's time to change it. The gear consists of 12 teeth and a hole (diameter 14 mm) - under the shaft. Unscrew the fixing bolt (a 10 wrench will help), remove the washer and pull out the gear. Be careful not to lose the key (it is small, located in the gear). Put the key on the new gear and put it back in place by doing the steps in reverse order.
This work, unlike those described, is more painstaking and will require skill and time. First, remove the motor box that is on the concrete mixer, the belt - this way you will get to the pulley. It is made of plastic. Therefore, it is quite logical that over time the pulley hole will round out and it will not be able to rotate the shaft.
The pulley is attached to the snap ring on the back of the box. This means that you can not do without a complete analysis of the structure.
There is a “plus” in this - you will fully appreciate the condition of the bearings. If there are distortions and jamming, they will also have to be changed. Then it remains only to collect everything and return the concrete mixer to its previous state.
In principle, as you can see, making repairs is not so difficult. But still it is better that the concrete mixer does not break. You can postpone the breakdown period by adhering to some simple tips, with the help of which you can not think about repairs for a long time:
always clean the concrete mixer after use, especially make sure that dust from cement and mortar does not get into the mechanism and motor;
do not overload the tool, do not try to make more concrete at a time than is allowed by the instructions;
try to keep the concrete mixer in the form in which you purchased it - in this case, you can take advantage of the repair guarantee, which will be carried out by specialists.
VIDEO Repair of concrete mixers is an important issue, because today it is very difficult to find a building that does not use concrete. With a large volume of consumption of this material, it is difficult to do without a concrete mixer.
A concrete mixer is often used in the construction of buildings where a large volume of concrete is needed.
This device is operated under heavy loads on its mechanical and electrical parts. In such conditions, periodic repairs are inevitable, you should be prepared for this and have the necessary spare parts.
To repair a concrete mixer, you will need the appropriate spare parts and the following tools:
puller for bearings;
three-arm puller;
hammer;
pliers;
vise;
screwdriver;
chisel;
wrenches;
gas key;
Adjustable wrench;
knife;
tester;
calipers.
For repair you will need: pliers, screwdrivers, keys, hammer, knife, caliper.
A concrete mixer is a device for obtaining a ready-to-use concrete solution by mixing dry ingredients with water in predetermined proportions. In domestic conditions, gravity-type equipment is used. The design includes the following main parts for concrete mixers: a drum with blades, a traverse, a frame (frame), a turning mechanism, a latch, a running gear and an electric part.
The drum is a mixing chamber, i.e. capacity of different volume depending on the capacity of the equipment. Inside there are blades for mixing the mixture. The drum is mounted on the traverse through a rolling bearing. The rotation of the drum is provided by an electric motor mounted on a tension plate. The mixing chamber is driven by a V-belt and gear transmission.
A large gear (ring gear) is placed on the drum, to which a significant rotational force is applied. The container rotation mechanism, including a flywheel, is designed to set the desired angle of its location during rotation, loading and unloading of the mixture, and manually. The desired position is fixed with a latch.
Timing belts are often replaced
Repair of concrete mixers is due to wear of heavily loaded parts or operation with violations. The most loaded are the drive elements.
Sometimes, spare parts are needed, such as bearings and a gear ring, which perceive an increased load, especially when the mass loading mode, speed or time modes are violated. The most requested spare parts are belts.
Gear failure is usually the result of improper operation of the equipment. A common misconception among the owners of equipment is the belief in the need for frequent lubrication of the crown and gear to reduce the force on the engine, although in practice the load increases. During operation, cement and sand stick to the teeth, which leads to increased friction and wear of the metal.
In addition to natural wear and tear, the concrete mixer fails due to improper cooling, from excessive loads or due to improper operation of the gearbox. As a rule, the repair of a concrete mixer consists in replacing a damaged part, for which spare parts are used that, according to their characteristics, fully correspond to the installed elements of the gearbox, running gear or electrical part.
The serviceability of the start button is checked by the tester, the idle button is changed.
Usually, such a repair of a concrete mixer is done by the owner of the equipment himself. A huge load is perceived by the ring gear of the drum, especially when the solution is fully or over-loaded. The crown can be made of high-strength plastic or cast iron, but even cast iron parts can fail during the operation of the installation, most often due to a factory defect caused by low-quality castings. In this regard, high-strength plastic gears are recommended in domestic concrete mixers. This part has a sector non-monolithic design, which allows you to change a specific sector of the part that has failed when repairing a concrete mixer with your own hands.
In addition to manufacturing defects, the cause of crown failure can be friction when it comes into contact with concrete during rotation. A sufficiently loaded element is a bearing, which can also suffer during overloads.
The electrical part of the installation is represented by an electric motor, a magnetic starter, a starting capacitor and a start button. The most common reason that the engine does not want to start is a starter and button malfunction. The operability of the starter is checked by a tester - the integrity of the coil and the fit of the contacts are determined.
A burnt coil can be replaced, but it is recommended to change the entire starter, as the contacts also wear out significantly.
The worn bearing is replaced with a new one and lubricated with lithol.
The operation of the start button is checked by the tester by the operation of the contacts, the non-working button is replaced. In the capacitor, the integrity of the gasket is specified. The most consumable spare parts of a concrete mixer are drive belts (for example, in the SBR-132 plant, a five-strand belt 610 mm long). Replacement is carried out in the following order. The cover is removed. Loosen motor mounting screws. Then he, together with the plate, rises until the belt loosens. The belt is replaced with a new one, and the engine is lowered, the desired belt tension is fixed.
To repair the concrete mixer with your own hands, it is important to carefully remove the drum. For this, a gas wrench, a wrench (usually 13 mm) and a three-arm puller are used. The lock nut and the drum fastening nut are unscrewed with a gas wrench. Then the fixing bolt located on the side is unscrewed with a wrench. The puller is fixed and the shaft is squeezed out. Bearings are replaced in the following order. Usually bearing 6203 is used in concrete mixers, and it must be prepared.
Removing the ring gear in the concrete mixer.
First, the box with the electric motor is removed. Then the drum is removed from the shaft, the drive gear and the key securing it are removed. To carefully remove the bearings, use a puller designed for this purpose. The puller is installed from the gear mounting side. The bearing is replaced with a new one and carefully lubricated with lithol. When pressing in a new bearing, a puller is also used. In the absence of a puller, the operation of removing the bearing will have to be carried out using a pipe according to the size of the bearing. The extraction of the part is carried out with sharp, neat blows on the pipe. The pipe must be installed strictly along the inner race of the bearing.
Removing the ring gear also has its own procedure. To remove it, it is necessary to remove the box with the electric motor along with the pulley. Then the retaining ring is unclenched and removed. The ring gear is removed and the section that has failed is replaced. At the same time, it is recommended to check the condition of the bearings and lubricate them with lithol.
The task of the concrete mixer is to ensure that the mixture loaded into the drum is in continuous motion all the time until it is completely mixed. The device works in this order. The drum is set and fixed the desired angle of inclination. Water is poured into the chamber, and then sand, cement and aggregate (crushed stone) are poured in proportions corresponding to the selected concrete recipe. The electric motor is turned on and the concrete mass is mixed. At the end of the process, the drum is released from the retainer and overturns, and the mass spontaneously flows out. The most widely used equipment is a two-shaft type.
In this design, the mixing of the solution is carried out using two types of blades - central and external - and the corresponding scrapers. The blade has a system of a bracket and a spring shock absorber, which allows the blade to move when rubble gets under it.The blades and scrapers are in constant motion, which ensures uniform mixing of the ingredients of the solution. The design of the concrete mixer is not very complex. Repair of the unit can be done by hand if the appropriate spare parts are available.
This article will focus on the repair of the SBR-132A concrete mixer with your own hands.
In general, I want to say that the concrete mixer is quite reliable. It has already withstood two "self-made" foundations, and this is more than 100 m 3 of concrete, plus plinths for these houses, floors, and so on little things. They make it here in Russia, in the city of Lebedyan. Personally, I bought it from this factory. I immediately bought a pair of belts in reserve, a plastic driven pulley and a drive sprocket.
The breakdown manifests itself by turning off the concrete mixer when the button is released. Simply put, press the green button - the stirrer turns. We let go - it, the infection, stops. This is not such a big sadness, and the simplest breakdown, but also the most frequent. The fact is that this is not quite a button, but a KJD17 magnetic starter. The thing is very convenient, unlike a simple knife switch, and made for the sake of our safety. When the light is turned off, the starter button will open, and when the light is suddenly turned on, it (the stirrer) will no longer start as suddenly and will not hurt the poor builder, who at that time decided to put his finger between the gears. That is, it is a simple "protection against a fool." Treating the disease is quite simple.
We remove the casing on which the button hangs.
I have it gray, screwed with four screws. under a crosshead screwdriver. Just the height of engineering. Developers. Try to unscrew these 4 self-tapping screws in the field. Well, this is a concrete mixer, and picking out concrete from these “crosses” on self-tapping screws is a dubious pleasure. Thousands of users remember you for this not in the best words. If only they put an imbus there with rubber plugs or something. In general, the first couple of times you can unscrew it with a screwdriver, and then only with pliers with matyuks.
Okay, open it. Carefully remove the cover and see that 5 wires go to the starter from the inside.
Disconnect them carefully. Unscrew the button (it is also on two screws).
Now this button must be disassembled in order to clean the contacts that are inside. With a thin screwdriver, we press on the two latches that are located on the top and bottom of the button. We remove the front. We see a small "penny" with a leg. The leg is slightly bent, so the “nickle” must be put the way it was, otherwise it will not work. We take off the "penny". On the reverse side, you will most likely see a small black soot. Because of this soot, in fact, the mixer does not work as it should. We clean everything with a soft sandpaper. We look at the core that is in contact with this “penny”, we clean it too. We collect everything in the reverse order. We rejoice in the new working day!
I want to draw your attention to the fact that the KJD17 magnetic starter is 5-pin. The fifth contact goes to the emergency thermostat of the engine and, at a certain elevated temperature, cuts off the power from the motor.
The motor works, tries, buzzes merrily (obviously without signs of anguish and bites), but the agitator does not turn. Fixing it!
The belt is a consumable item, just like in a car. The SBR-132A is fitted with 5PJ 610 (a five-ribbed belt 610 mm long). With its replacement, everything is simple. We remove the protective cover, disconnect the contacts from the starter so as not to interfere. Slightly loosen the two bolts that are on the back side and secure the motor. Raise the motor up a little with your hands and remove the belt. This is if it is still standing there))) Usually, if it buzzes and does not turn, then the agitator removed or tore the belt for you, and nothing needs to be removed. It is put on without much effort, at first it clings to a small pulley that is on the motor. Then it pulls on the top. After you need to tighten the belt. This is best done with a friend. A friend presses on the box, and you tighten those two bolts that you loosened before removing the belt.
The concrete mixer works, turns, and in order to extend the life of the drive gear and rims, you need to get used to the fact that before starting the shift, all these things need to be thickly greased with lithol. We turn the bowl upside down, turn on the mixer and spread lithol on the crowns with a spatula. The stirrer rumbles rather, champing and thereby showing that she is feeling good now))))
Jokes are jokes, and sooner or later the gear will turn into this:
It will begin to slip along the teeth of the crown and deliver a lot of not very pleasant impressions. It's time to change it! I don’t know where to buy, I take it directly at the factory in Lebedyan, since it is not far from us. The gear has 12 teeth and an inner hole for the shaft 14 mm in diameter.
Replacement! With a certain skill, the bowl does not need to be removed, it is enough to unscrew the fixing bolt with a 10 key,
remove the washer and pull out the gear. Carefully! There is a small key there, so you need not lose it. It’s all so easy and accessible in the photo above, because the pear is removed, and if you’re too lazy to remove the pear, then you need to be smart and use all the work of fine motor skills of your fingers to get it out of there. But it's real! Checked! 4 times already.
The pulley is made of plastic. The shaft on which this pulley is put on is round and milled on one side. So, the whole trouble is that when the hole on the pulley becomes completely round, it turns freely on the shaft. Accordingly, the motor is spinning, the pulley is spinning, but the shaft is not ((((
It would seem, why change it, this pulley? I removed the cover from the motor box, as when replacing the belt, removed the belt and removed the pulley. It seems to hang out, but it doesn’t come off, even if you crack it. But here's the thing: the pulley on the back of the box is attached with a retaining ring, so it doesn't make much sense to make efforts to remove it without removing the box with the motor. Therefore, unscrew the two nuts and remove the two bolts that hold the box to the frame. The box will be removed along with the pulley and a bare shaft will remain. Now it remains to unclench and remove the retaining ring. The pulley will fall out by itself. It is completely unclear why it is impossible to make a pulley not from metal, but out of the corner of my ear I heard that on modern SBR-132 they have already begun to make metal ones. But these are rumors.
If you have already removed the entire box and saw the shaft, then it costs nothing to check it for bearing wear. Turn the shaft with your fingers, make a few turns, if everything is fine, then change the pulley and assemble everything back, if something sticks and the shaft rotates unevenly, congratulations))) you got to replace the bearings. Read the next paragraph.
The feeling that the stirrer has become old and there is no longer that former agility. Spins like fast, but does not start the first time. When it seizes, the motor no longer buzzes merrily, but rather hums strainedly. In general, there is a feeling that you need to buy a new mixer, but everything is not so tragic. It's all the fault of a pair of bearings that stand on the shaft, on which a pulley is mounted on one side, and a gear on the other. Here he is, our hero! And two old men who have outlived their own)))
This is a 203 bearing or 6203 according to the international classification. It costs like two loaves of sliced bread, so the repair is not very expensive. We remove the box with the motor, as in the case of replacing the pulley. We remove the pear of the concrete mixer. How to remove it, I will tell in the next paragraph. Remove the drive gear (see above). And we are left alone with this situation.
From the side of the gear, squeeze the retaining ring and remove it. Since I don't have a suitable puller, the shaft had to be knocked out with brute force. To prevent the frame from springing, I had to use a high-tech device called “board sawn to size”))) It looks something like this:
Unfortunately I don't remember the size. In general, carefully, but strongly, substituting a piece of wood on the shaft so as not to bend it, we knock out the shaft along with the bearings.
In the end, we have a shaft in our hands, on which two bearings hang, a bushing between it the size of the outer race of the bearing and a small spacer bushing. If there is a tool, then further manipulations are quite simple. If not, buy it - it will come in handy more than once!
We put the puller on the side where the gear was (the key, I hope, has already been pulled out) and press on the shaft, pulling out the bearings.
We change the bearings to new ones, lubricate the shaft with lithol and also put on new bearings with a puller. Or you can pick up a tube for the diameter of the shaft, and carefully hammer them into place, knocking strictly on the inner race of the bearing.
Then we assemble everything in the reverse order, not forgetting about all the spare parts, and enjoy the work of the concrete mixer.
Nothing complicated either, you need a gas wrench, an open-end wrench for 13 and our old friend - a three-legged puller.
We unscrew the lock nut with a gas wrench, and then the pear fastening nut.
Using a 13 key, unscrew the locking bolt on the side. Didn't a pear fall out?)) It's not scary! We install a three-legged puller and calmly squeeze out the shaft.
At some point, the pear will fall out. There will be adjusting washers on the shaft, try not to get them confused.
That's all! If you have questions, ask in the comments. Fotkal not all, as the repair will try to add more pictures for clarity! Good build everyone!
VIDEO Repairing a concrete mixer with your own hands is not an easy job, but sometimes you will have to face it.
To avoid breakage, it is recommended to remove mortar residues and cement dust from all parts of the concrete mixer after work.
Of course, if the owner is a responsible person, then he will immediately realize that:
after completion of work, the concrete mixer must be cleaned as thoroughly as possible, paying attention to the fact that cement dust and mortar residues do not get into the mechanisms and parts of the engine;
any construction equipment (and a concrete mixer too) has a warranty period for repairs, and we must try to keep it in such a form that the owner is not turned away from the doorstep in the workshop or service center due to the “worked-out look” of the equipment;
Before buying a concrete mixer, it is a good idea to find out the location of a repair and maintenance shop, or at least the address of a technician who can help if necessary.
Typical device of a concrete mixer.
Let's assume that the concrete mixer is operated correctly: the electric voltage does not jump, moisture does not get into the electrical part, the load rate is maintained. And then the owner comes up with the idea that it would be nice to lubricate the ring gear (the ring around the working tank) and gears.
That's just what you shouldn't do, because cement dust and sand settle on lubricated surfaces and increase the load on the motor, increase friction and contribute to faster metal abrasion.
"Dusty" working conditions will certainly require the need to repair the concrete mixer, but it turns out that some repair operations can be done by hand. This applies to the repair of the power button, the replacement of the ring gear, transmission belts, bearings, etc.
With your own hands, you should try to repair the concrete mixer under certain conditions:
The most common problem is the breakdown of the concrete mixer start button.
The owner has relevant experience in repairing all kinds of home appliances. Experience in repairing a motorcycle and a personal car will also come in handy.
In this case, the issue with the necessary tools is solved simply: a home kit or auto tools will do. But let's clarify, just in case, that you may need a tester (multimeter), indicator screwdrivers, a puller and sets of keys and screwdrivers of various configurations.
It is possible that during the repair of the concrete mixer it will turn out that the reason for the stop (breakdown) is a non-separable part: these may be bearings, gears or shafts that will require replacement.
The button for turning on the concrete mixer is a magnetic starter, and not just an on / off design. This is done for the safety of work, because. if the power is suddenly cut off, the unit will stop, and when the power is turned on, it will no longer work. The button must be pressed again, but there is a guarantee that the sudden activation of the concrete machine will not cripple anyone.
Schemes for switching on a single-phase asynchronous motor of a concrete mixer.
If the power button malfunctions, you just need to slowly and sequentially remove the protective cover, the button itself, examine and clean the connecting contacts. The button itself, by the way, is also disassembled and there is something to clean inside.
A breakdown is possible when the engine is running, and the working container (mixing drum) does not rotate. So, you need to check the drive belts. After the protective cover of the electric drive is removed, the picture opens like this: the belt is intact, not broken, but it is no longer suitable for work, or maybe it just slipped off. Or the belt just broke.
So, you need to put the old belt in place or buy a new one and put it on.
The procedure is not very complicated: two bolts that secure the engine are loosened, then a belt is placed. You need to start with a small pulley (from the engine), then move on to a large one. This procedure will require the help of a second person, because it will not be possible to tighten the belt by pulling the engine, and then tighten the two bolts alone.
The scheme of fastening the barrel on the racks.
The structure that connects all the elements of the concrete mixer is called the frame. It is a connection of profiles, pipes, wheels from below and other elements. A concrete mixer is a non-stationary tool, but it is not well suited for movement on an earthen surface, so it may be necessary to replace wheels, “weld” metal joints, etc. Experienced builders often pre-weld metal structures from a corner for greater stability.
More serious repairs are associated with the replacement of the pulley and bearings. You must also start by removing the engine box, removing the belt and getting to the pulley. The material of which the pulley is made is plastic, which means that sooner or later the pulley hole will become completely round and the pulley simply will not rotate the shaft.
There is one caveat: the pulley is attached with a retaining ring on the back of the box, which means that the structure must be disassembled to the end until one bare shaft remains.
But in this case, it will be possible to assess the condition of the bearings: if the shaft rotates smoothly, then everything is fine.
If there are distortions and jamming, then the bearings will have to be changed.
Video (click to play).
VIDEO
Drum with blades. This is the chamber in which the concrete ingredients are mixed. The volume of the drum may be different. It depends on the power of the device. The blades are located inside the drum and help to better mix the ingredients.
