After repairing the concrete mixer and eliminating any malfunctions in one or another part of it (or better, immediately after purchasing the equipment), you should try to use the device in the future so that similar or any other problems no longer arise.
If you try to follow all these not very complicated rules, then the concrete mixer will last quite a long time and you will not have to think about repairing it throughout its entire service life.
If the device fails, then even someone who is not a great specialist in the field of construction will be able to quickly repair concrete mixers with his 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 question that sooner or later arises before every builder or owner of this tool. Unfortunately, the breakdown of concrete mixers is a common phenomenon, and there are many reasons for this. First, enormous loads are placed on this device. Secondly, often the owners themselves do not pay proper attention to the instrument, they misuse and store it. It is also fraught with negative consequences, which often require repair work. Before getting down to business on your own, you need to study all the information, stock up on the necessary tools.
It is possible to repair a concrete mixer with your own hands only if you have experience in such work. Have a home appliances fix? 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 something like 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 losing your concrete mixer altogether.
In order to independently repair the unit, you will need a list of tools (of course, depending on the breakdown, the set may change). Among the main ones are pullers (three-blade 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 your knife, tester, and caliper ahead of time.
There are many reasons why concrete mixer repairs may be necessary. It happens:
when the unit loads more than the established rates;
the drum is untimely cleaned (this must be done after each use);
improperly and in improper storage of the tool.
A special place is occupied by the repair of consumable items - 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 support bearings and gear rims occurs much less often, all because their service life is much longer than the above parts.
Let's consider the main reasons for the breakdown 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 they are completely wrong! In this case, the load only increases. When working on the teeth, cement / sand clings, this increases friction and quickly abrades the metal.
Reducer. It wears out quickly due to poor cooling, overload. In this case, the part only needs to be replaced. There is even a chance that you will have to change the entire unit.
Gear ring. Significant mechanical stress is imposed on it. The material of this part is plastic or cast iron. More often cast iron parts become unusable (this is due to the low quality of casting). Therefore, it is better to install a plastic crown initially.
Shutdown buttons.Often the reason for the breakdown lies in them. This is expressed as follows: by pressing the button, the unit (motor) supposedly 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, the main condition is that it must have the appropriate number of contacts.
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The buttons in concrete mixers are magnetic actuators, not just an on / off design. This ensures the safety of work, because in the event of a sudden power outage, 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 cover (by unscrewing the screws that hold it), the button itself. View the detail, if necessary, strip the contacts. Also disassemble the button by cleaning it inside.
Sometimes it can happen that the motor works, but the container does not (no rotation occurs). In this case, the cause may be in the belts. Remove the protective cover from the drive and assess the situation. Most often, the strap just slips off - in this case, you need to put it in place. Sometimes, even if the belt is intact and not broken, it may not be suitable for further use. This means that you cannot do without buying a new one. To put it, loosen the bolts that attach the motor (there are two of them), put the belt. Start with a shallow 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 take place simultaneously.
Before replacing the gear and rims, you need to try to rehabilitate them - thoroughly lubricate 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) - for the shaft. Unscrew the fixing bolt (a key for 10 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, which 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 and it will not be able to rotate the shaft.
The pulley is attached to the corkscrew ring on the back of the box. This means that you cannot do without a complete analysis of the design.
There is also a "plus" in this - you will fully appreciate the condition of the bearings. If there are distortions and jams, 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, it is not so difficult to make repairs. But still it is better that the concrete mixer does not break. You can postpone the breakdown time by adhering to simple tips, with the help of which you can not think about repairs for a long time:
always clean the mixer after use, especially make sure that dust from cement and mortar does not get into the mechanism and engine;
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 use the guarantee of repair, which will be made by specialists.
VIDEO Repairing concrete mixers is an important issue, because today it is very difficult to find a construction that does not use concrete. With a large volume of consumption of this material, it is difficult to do without a concrete mixer.
The concrete mixer is often used in building construction 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:
bearing puller;
three-legged puller;
hammer;
pliers;
vice;
screwdriver;
chisel;
wrenches;
gas key;
Adjustable wrench;
knife;
tester;
calipers.
For repairs you will need: pliers, screwdrivers, keys, a hammer, a knife, a vernier caliper.
A concrete mixer is a device for obtaining a ready-to-use concrete solution by mixing dry ingredients with water in specified proportions. In domestic conditions, equipment of the gravitational type is used. The design includes the following main parts for concrete mixers: drum with blades, traverse, frame (frame), swing mechanism, lock, undercarriage and electrical part.
The drum is a mixing chamber, i.e. capacity of different volumes depending on the capacity of the equipment. Inside there are blades for mixing the mixture. The drum is mounted on the crosshead through the rolling bearing. The rotation of the drum is provided by an electric motor fixed on the tension plate. The mixing chamber is driven by a V-belt and a gear drive.
A large gear (ring gear) is placed on the drum, which receives a significant rotational force. The mechanism for turning the container, including a flywheel, is designed to set the desired angle of its location when rotating, loading and unloading the mixture, and manually. The desired position is secured with a latch.
Timing belts are often replaced
Repair of concrete mixers is caused by wear of heavily loaded parts or improper operation. The most loaded are the drive elements.
Sometimes, you need spare parts such as bearings and the crown of the gearing, which take an increased load, especially when the mass loading mode, speed or time conditions are violated. The most popular spare parts are belts.
Gear failure is usually the result of equipment misuse. A common misconception of the owners of technology is the belief in the need for frequent lubrication of the ring and gear to reduce the effort on the engine, although in practice the load increases. During operation, cement and sand adhere to the teeth, which leads to increased friction and wear on the metal.
In addition to normal wear and tear, the concrete mixer breaks down due to improper cooling, excessive loads or improper gearbox operation. As a rule, the repair of a concrete mixer consists in replacing the damaged part, for which spare parts are used that, in their characteristics, fully correspond to the installed elements of the gearbox, chassis or electrical part.
The serviceability of the start button is checked by a tester, the inoperative button changes.
Usually, such a repair of a concrete mixer with his own hands is carried out by the owner of the equipment himself. A huge load is perceived by the drum ring gear, especially with a full or overestimated solution load. 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 casting. For this reason, high-strength plastic gears are recommended for household concrete mixers. This part has a non-monolithic sector design, which allows you to change a specific sector of a part that is out of order when repairing a concrete mixer with your own hands.
In addition to factory defects, the cause of crown breakage can be friction when it touches concrete during rotation. A sufficiently loaded element is a bearing, which can also suffer from overloads.
The electrical part of the installation is represented by an electric motor, a magnetic starter, a starting capacitor and a starting button. The most common reason for the engine not wanting to start is a malfunctioning starter and button. The performance of the starter is checked by a tester - the integrity of the coil and the contact of the contacts are determined.
A burnt-out coil can be replaced, but it is recommended to change the entire starter, as the contacts also wear out significantly.
The worn out bearing is replaced with a new one and lubricated with lithol.
The operation of the start button is checked by a tester by the actuation of the contacts, the inoperative button is replaced. The integrity of the gasket is checked in the condenser. The most consumable spare parts of a concrete mixer are drive belts (for example, in the SBR-132 unit - a five-strand belt 610 mm long). Replacement is carried out in the following order. The cover is removed. The screws that secure the motor are loosened. Then it rises together with the plate until the belt looses. The belt is replaced with a new one, and the engine is lowered, the required belt tension is fixed.
To repair a concrete mixer with your own hands, it is important to carefully remove the drum. To do this, use a gas wrench, a wrench (usually 13 mm) and a three-arm puller. The gas wrench is used to loosen the lock nut and the drum fastening nut. Then, use a wrench to unscrew the fixing bolt located on the side. The puller is attached and the shaft is squeezed out. The bearings are replaced in the following order. Usually bearing 6203 is used in concrete mixers, and this must be prepared.
Removing the ring gear in a 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 that secures it are removed. To carefully remove the bearings, use a puller designed for this purpose. The puller is installed from the side of the gear attachment. 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 part is removed by sharp, accurate 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 order. To remove it, you must remove the box with the electric motor together with the pulley. Then the retaining ring is opened and removed. The toothed ring is removed and the out-of-order section 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 keep the mixture loaded into the drum in continuous motion until it is completely mixed. The device works in this order. The desired tilt angle is set and fixed to the drum. 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 is mixed. At the end of the process, the drum is released from the lock and overturns, and the mass spontaneously flows out. The most widespread is the equipment of the two-shaft type.
In this design, 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 in the solution. The construction of a concrete mixer is not very complex. The unit can be repaired with your own hands if the appropriate spare parts are available.
This article will focus on repairing the SBR-132A concrete mixer with your own hands.
In general, I want to say that the concrete mixer is quite reliable. Has already withstood two "self-weight" foundations, and this is more than 100 m 3 of concrete, plus plinths for these houses, floors and so on in little detail. They make it in Russia, in the city of Lebedyan. Personally, I bought it at this particular plant. Immediately in reserve I bought a pair of belts, a plastic driven pulley and a drive sprocket.
Breakage manifests itself by turning off the concrete mixer when the button is released. Simply put, we press the green button - the mixer turns. Letting 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 really a button, but a KJD17 magnetic starter. The thing is very convenient, unlike a simple switch, and is made for the sake of our safety with you. When the light is turned off, the starter button will open, and when the light is suddenly turned on, it (the stirrer) will not start up suddenly and will not hurt the poor builder, who at that time took it into his head to stick his finger between the gears. That is, it is a simple "foolproof". Treating the sore is quite simple.
We remove the cover on which the button hangs.
I have it in gray, screwed on with four self-tapping screws. for a Phillips screwdriver. Just the top of engineering. Developers. Try unscrewing these 4 screws in the field. 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 in not the best words. If only they put the 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 swearing pliers.
Okay, unscrewed. Carefully remove the cover and see that 5 wires go to the starter from the inside.
Disconnect them carefully. We unscrew the button (it is also on two self-tapping screws).
Now this button must be disassembled in order to clean the contacts that are inside. With a thin screwdriver, press on the two latches that are located at the top and bottom of the button. We remove the front part. We see a small “penny” with a leg. The leg is slightly bent, so the “penny” must be placed as it stood, otherwise it will not work. We remove the "penny". On the back side, you will most likely see a small black carbon deposit. Because of this carbon deposits, in fact, the mixer does not work as it should. We clean everything with meeeeee sandpaper. We look at the core, which is in contact with this "penny", we clean it too. Putting it all in reverse order. We are glad to the new working day!
I would like 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 engine.
The motor works, tries, hums merrily (obviously without any signs of tearing and nibbling), but the agitator does not turn. Fixing!
The belt is a consumable item, just like in a car. The SBR-132A is equipped with a 5PJ 610 (five-strand belt 610 mm long). With its replacement, everything is simple. We remove the protective cover, disconnect the contacts from the starter so that it does not interfere. We slightly loosen the two bolts that are on the back side and secure the motor. Lift the motor up a little with our hands and remove the belt. This is if it is still there))) Usually, if it buzzes and does not twist, then the mixer has removed or tore the belt for you, and you do not need to remove anything. He puts on without much effort, at first it clings to a small pulley that is on the motor. Then it is pulled over the top. Then you need to tighten the belt. It is better to do this 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 crowns, you need to get used to the fact that before starting the shift, all these things need to be thickly greased with lithol. Turn the bowl over with the neck down, turn on the stirrer and use a spatula to spread the lithol on the crowns. The agitator hums quite, humming and thereby showing that it is good now))))
Jokes as a joke, 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 buy it directly from the plant in Lebedyan, since it is not far from us. The gear has 12 teeth and an internal shaft hole of 14 mm in diameter.
Replacement! With a certain skill, it is not necessary to remove the bowl, 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 must not lose it. In the photo above, everything is so easy and accessible, because the pear has been removed, and if you are lazy to remove the pear, then you need to be smart and use all the work of fine motor skills of the fingers in order to fish it out from there. But it's real! Checked! 4 times already.
The pulley is made of plastic. The shaft that this pulley slides on is round and milled to 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 turns, the pulley turns, but the shaft does not ((((
It would seem, why change it, this pulley? He removed the cover from the motor box, as when replacing a belt, removed the belt and removed the pulley. It seems to hang out, but it doesn’t come off, even though you crack. But the point is this: the pulley on the back of the box is fastened with a retaining ring, so it makes little sense to make efforts to remove it without removing the box with the motor. Therefore, we unscrew the two nuts and remove the two bolts that hold the box to the frame. The box will be removed together 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 of metal, but out of the corner of my ear I heard that modern SBR-132 has already begun to make metal. But these are rumors.
If you have already removed the entire box and saw the shaft, then it is worth 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 put everything back together, if something sticks and the shaft turns unevenly, congratulations))) you got to replace the bearings. We read the next paragraph.
The feeling that the agitator has become old and there is no longer that former agility in it. It seems to be spinning quickly, but it does not start the first time. When it sticks, the engine no longer buzzes merrily, but rather a strained hum. In general, there is a feeling that you need to buy a new mixer, but everything is not so tragic. It's all to blame for a pair of bearings that stand on a shaft on which a pulley is attached 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 bearing 203, or according to the international classification 6203. It costs like two loaves of sliced bread, so repairs are not very expensive. We remove the box with the motor, as in the case of replacing the pulley. We remove the concrete mixer pear. I will tell you how to remove it 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 do not 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 together 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 an outer bearing race and a small spacer sleeve. If there is a tool, then further manipulations are not difficult at all. If not, buy - 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.
Also, nothing complicated, you need a gas wrench, open-end 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. Pear didn't 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 shims on the shaft, try not to get them confused.
That's all! If you have any questions, ask in the comments. Not all photos, as the repair progresses I will try to add more photos for clarity! Good construction, everyone!
VIDEO Do-it-yourself concrete mixer repair is not an easy job, but sometimes you 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 the end 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 way that the owner is not deployed from the door in the workshop or service center because of the “worn-out” type of equipment;
Before purchasing a concrete mixer, it would be a good idea to find out the location of the repair and maintenance workshop, or at least the address of a technician who can help if necessary.
Typical concrete mixer device.
Let us assume that the concrete mixer is operated correctly: the electric voltage does not jump, moisture does not enter 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 container) and gears.
This is exactly what you should not do, since cement dust and sand settle on lubricated surfaces and increase the load on the motor, increase friction and contribute to faster abrasion of the metal.
"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, replacement of the ring gear, transmission belts, bearings, etc.
You should try to repair a concrete mixer with your own hands if certain conditions are met:
The most common problem is the breakage of the power button of the concrete mixer.
The owner has relevant experience in the repair of all kinds of home appliances. Experience in motorcycle and personal car repair will come in handy too.
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 different configurations.
Perhaps, during the repair of a concrete mixer, it turns out that the reason for the stop (breakdown) is a non-separable part: it may be bearings, gears or shafts that will need to be replaced.
The on / off button of the concrete mixer is a magnetic actuator, not just an on / off design. This is done for the sake of work safety, because in the event of a sudden power outage, the unit will stop, and when power is applied, it will no longer work. The button must be pressed again, but there is a guarantee that a sudden start of the concrete machine will not injure anyone.
Schemes for switching on a single-phase asynchronous concrete mixer motor.
In case of a power button malfunction, you just need to slowly and sequentially remove the protective casing, the button itself, examine and clean the connecting contacts. The button itself, by the way, is also understandable 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, it is necessary to check the drive belts. After the protective cover of the electric drive is removed, the picture opens as follows: the belt is intact, not torn off, but is already unusable for work, or maybe it just slipped off. Or the belt just broke off.
This means that you need to replace the old belt or buy a new one and put it on.
The procedure is not very complicated: two bolts that secure the engine are loosened, then the belt is installed. 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 tensioning the belt by pulling the engine and then tightening the two bolts alone will not work.
Barrel mounting scheme on racks.
The structure that connects all the elements of the concrete mixer is called the bed. It is a connection of profiles, pipes, wheels from the bottom and other elements. A concrete mixer is a non-stationary tool, but it is not very suitable for movement on the earth's 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 repair work involves replacing the pulley and bearings. You also need to start with the fact that the engine box is removed, the belt is removed and you get to the pulley. The material from which the pulley is made is plastic, which means that sooner or later the pulley hole will become completely round and the pulley will simply 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 seizures, then the bearings will have to be replaced.
Video (click to play).
VIDEO
Drum with blades. This is the chamber in which the concrete ingredients are mixed. The drum volume may vary. It depends on the power of the device. The paddles are inside the drum to help mix the ingredients better.
