Mechanical (electromechanical) guillotine shears NA 3121 are industrial equipment designed for direct cutting of sheet or strip metal (steel, non-ferrous metal products or alloys). Mechanical (electromechanical) guillotine shears NA 3121 are industrial metalworking equipment used in individual and mass production in tool and mechanical repair shops.
Design features of crank guillotine shears NA3121
The scissors are made with top drive.
Rotation from the electric motor is transmitted through a V-belt drive, clutch-brake, spur gearbox to the eccentric shaft and then through the crank mechanism to the knife beam.
The scissors frame is a welded structure consisting of two posts connected by channels.
The table rests on the racks, to which the lower knives are attached with screws. By moving the table horizontally, the gap between the upper and lower knives is adjusted. Front and side supports are attached to the table.
The knife beam is a welded L-shaped structure, reinforced with ribs. The upper knives are attached to the knife beam.
Pneumatic balancers serve to compensate for the mass of the cutter beam, as well as to reduce dynamic loads during operation of the scissors.
The pneumatic multi-disc friction clutch-brake is rigidly locked and located at the left end of the drive shaft.
For measured cutting of strips, the scissors are equipped with a back stop, which is installed on the back side of the knife beam. The back stop is installed using a screw mechanism driven manually from the handwheel.
When cutting, the sheet is pressed by a pressure beam that works in concert with the knife beam. The necessary clamping forces are provided by springs that are placed in the cups of the clamping beam.
The electrical circuit ensures the operation of the scissors in single and automatic strokes.
The scissors are controlled by push-buttons and pedals.
Combined lubrication of the main mechanisms.
Components of guillotine shears NA3121
Specification of components of guillotine shears NA3121
- Bed - NA3121-11-001
- Knife beam - NA3121-31-001
- Pressure beam - NA3121-32-001
- Drive - NA3121-21-001
- Helical gearbox - NA3121-22-001
- Drive shaft - NA3121-23-001
- Back stop - NA3121-33-001
- Balancer - NA3121-45-001
- Fencing - NA3121-71-001
- Lubrication system - NA3121-81-001
- Air duct - NA3121-43-001
- Reza zone fencing - NA3121-72-001
- BVK installation - NA3121-44-001
- Cutting line lighting - NA3121-76-001
- Control box - Ya9102
Repair of hydraulic guillotine shears HACO in St. Petersburg
Guillotine shears are a mechanism designed for cutting sheet material. The main detail in the design of such scissors is a movable knife that moves in one plane.
The main advantage of guillotine shears
is determined by their design - immediately at the moment of cutting, much less pressure is applied to the material than is usually required to perform cutting. This is a very effective tool. Another disadvantage is the inability to cut complex parts, however, if you need to make a simple cut, guillotine shears are the most economical and optimal choice.
HACO scissors have a rigid design, which is ideal for use in both mass production and small enterprises, and the product does not lose accuracy as the volume of work increases.
The manufacturer HACO has extensive experience in the market and is constantly improving its products by introducing new technologies. Thus, to control HSL machines, hydraulic cylinders are used in the upper part of the product. The openness of the back side of the tool gives the worker access to the workpiece.
Operation of HACO scissors
HACO devices operate on the swing beam principle (mod.SST), where a small angle of inclination of the blades ensures a result of the required quality and minimizes the side effect of deformation of the sheet of material. This approach to the design of products makes it possible to minimize the wear of knives as a result of operation.
HACO machines are distinguished by ease of control and ease of maintenance of the mechanism, which is largely facilitated by its simplicity. The guide parts of the products have low wear. The machines have a reliable welded frame, for the manufacture of which only high-strength structures are used, which significantly increases the cutting accuracy and reduces the amount of metal deformation.
Repair of HACO hydraulic guillotine shears in St. Petersburg
Hydraulic guillotine shears , like any other mechanism, are subject to various damages that may require repair. IP Emelyanov I.G. in St. Petersburg can repair the following typical faults:
- Wear of knife beam guide bearings. This malfunction occurs due to prolonged use of the product.
- Incorrect cut. It can occur as a result of an increase in the gap between the legs and wear of the knife beam guides. The operation of guillotine shears requires constant attention and care of the mechanism; you must not forget to grind the cutting edges of the knives.
- Replacement of bearings and guides of the back stop.
- Replacement of hydraulic cylinder repair kits.
- The limit switches may be faulty. The consequence of such a breakdown is a change in position.
There are other damages that IP Emelyanov I.G. will help to cope with. in St. Petersburg
srfatlant.ru
Design of guillotine shears NA3121
The shears consist of a frame, knife and pressure beams, drive, drive shafts, engagement clutch, back stop, balancer, brakes, guards, electrical and lubrication systems, and protective grille.
Frame of guillotine shears NA3121
The bed is the base unit on which all other scissor units are attached. The frame is a welded structure consisting of two racks connected to each other by channels.
The table rests on the racks, to which the lower knives are attached with screws.
To adjust the gap between the table knives and the knife beam, the table is moved with bolts screwed into the ends of the frame with the table fastening bolts relaxed. When regrinding, adjusting the knife height is done by grinding the spacers located under the knives.
The table has extensions with T-slots.
On the right edge of the table there is an extension fixed with pins, in the T-shaped groove of which the cross-cut stop is attached. To perform longitudinal cutting, this stop is removed.
Drive drive shafts of guillotine shears NA3121
The scissors are driven from an electric motor through a V-belt transmission to the flywheel, through gears and a clutch to the crankshaft.
The electric motor is attached to a sub-motor plate, hinged on the frame. Belt tension is adjusted using the eye bolt nuts.
Scissor clutch NA3121
At the left end of the crankshaft, a keyed engagement clutch is installed in the gear hub.
Bushings 1, 2, 3 are stationary in the gear hub. The remaining parts are connected to the crankshaft. The rotating (working and locking) keys of the engagement clutch are activated by springs 6 and, turning, are captured by the semicircular grooves of the sleeve 2.
Bushings 8 and 9, having semicircular grooves, complement the sockets for the round ends of the key. The right end of the working key is equipped with an easily detachable shank 4, which, when the scissors are in operation, disables the keys connected to each other by levers 5. When the keys are turned on, their angle of rotation is limited by the groove of the drive sleeve 8.
Knife beam of scissors NA3121
The knife beam is an L-shaped welded structure reinforced with ribs. The back stop is attached to the knife beam.
The force from the crankshaft is transmitted to the knife by two connecting rods; in the upper position, the beam is held by balancing springs, pivotally connected to the beam, and during repairs, it is fixed in the upper position by two Ø25 pins inserted into the hole. knife beam guides.
Clamp and protective grid of scissors NA3121
While the scissors are working, the sheet being cut is pressed against the table by a pressure beam. When the knife beam moves downwards, the clamping beam, under the action of springs, lowers and presses the sheet, and first the sheet is pressed, and then the cutting begins. This is achieved by installing the beam at a height of 24 mm, and the knife - 26 mm from the table surface.
The lifting of the clamp is carried out by the stops of the knife beam, resting against the clamping plates.
The clamping force is adjusted using nuts that compress the spring of the clamping beam.
A protective grille is attached to the guides of the pressure beam, protecting the worker’s hands from falling under the pressure. When the scissors are working, the grille is lowered: the M8X40 screw on the left presses the microswitch rod, and the screw on the right limits the rotation of the grille to the clamp.
If necessary, the grille can be raised up, but turning on the scissors is impossible - the switching contacts are open. The grille is held in the lowered and raised position by a 2X16 spring.
Rear scissor stop NA3121
The back stop is installed on the back side of the knife beam and serves as a stop for the sheet during cross cutting. The back stop consists of two cylindrical racks, moved manually by handwheels sitting on gear shafts meshed with the racks. By moving the slats, the stop line is set at the required distance from the edge of the knife, which achieves measured cutting of the sheet using the back stop.
Scissor balancer NA3121
The balancer is used to hold the knife beam in the upper position after each single stroke - when repairing scissors or changing knives. It consists of two sets of springs installed in cups welded to the upper channel of the frame. The rods are hingedly connected by axes to the knife beam. When the beam is lowered during cutting, the rods compress the springs. During the reverse stroke, the springs, unclamping, help lift the knife beam. Both sets of springs are rated at 1.0 ton with the beam in the top position.
Scissor brake NA3121
An intermittent brake is mounted on the right end of the crankshaft. The frequency of braking is achieved due to the eccentric location of the pulley relative to the crankshaft axis.
Braking occurs when the knife beam is in the upper position, which prevents it from running under the influence of inertial forces.
Electromagnetic control of shears NA3121
When you press a button or pedal, an electromagnet is turned on, the armature of which turns the fork with a pin, releasing the shank that engages with it and is connected to the working key. After that, under the action of the key springs, the crankshaft turns and turns on. There is a cut. If the operator does not release the button or pedal in the “Single stroke” mode, an electrical lock is activated (see the electrical equipment section).
To repeat the working stroke, the button or pedal must be released, then pressed again. During automatic operation, the electromagnet armature is set to a stroke of 40 mm, and when operating on single strokes - to 20 mm.
Scissor guard NA3121
The shear guard is made of 1.6 mm thick sheet steel and serves to protect the rotating parts of the shears. The guard consists of four casings that cover the motor pulley and the V-belt flywheel, six drive shafts and the scissor brake.
All casings are attached to the frame with M10 bolts.
Centralized lubrication of scissors NA3121
The main rubbing surfaces are lubricated from a manual pumping station through feeders. Lubrication is carried out through all individual grease nipples installed on the scissors using a manual syringe. The drive gears are lubricated by applying grease to the gear teeth respectively.
During operation, the scissors must be lubricated so that the lubricant comes from the side bearing locations. Any grease that comes out of the gaps must be wiped off. It is necessary to periodically check the condition of the oil nipples and oil passage holes in the parts and be sure to clean them. At least once every three months, the lubrication holes should be flushed with clean kerosene.
Overhaul of guillotine shears – Orenburg Press Machine Plant
Overhaul of guillotine shears
The Orenburg Press Machine Plant, being a manufacturer, also provides services for the overhaul of guillotine shears .
Structural elements of equipment wear out over time. The most common reasons for guillotine failure are the following:
- failure of knives;
- wear of bronze bushings;
- wear of the knife beam guides, leading to widening of the gap between the knives;
- loss of cutting power due to wear of rubber seals;
- failure of limit switches, leading to non-stop operation of the knife beam or stopping it in the wrong position;
- disruption of the operation of the electrical circuit of the mechanism as a result of replacing parts with their analogues, etc.
Specialists from our plant will perform preliminary diagnostics of the guillotine, produce and replace all the necessary components, bushings, liners, knives and other structural components. Our own production of components allows us to significantly reduce the cost of repairing guillotines. Also, specialists will set the gaps between the knives and perform other assembly work with maximum precision.
List of works for major repairs
of guillotine shears:
- Drawing up a defective list of scissors for completeness of mechanical parts and electrical equipment.
- Complete dismantling and disassembly of all components.
- Cleaning, rinsing and wiping scissor parts.
- Troubleshooting, inspection, sorting of parts.
- Clarification of the previously compiled defective list of parts requiring restoration or replacement.
- Grinding the table, knife beam, knives.
- Processing of the bed, cutting mechanism and other basic parts.
- Manufacturing of bronze bushings and liners.
- Repair of the crank shaft with replacement of rolling and sliding bearings.
- Replacing the lubrication system.
- Repair of the pneumatic system (pneumatic distributor) for scissors with a pneumatic clutch.
- Repair of the electrical cabinet with replacement of installation equipment.
- Assembling scissors with restoration of electrical wiring
- Repair of guides of pressure and knife beams. Exhibition of standards of accuracy and clearance between knives.
- Running in the scissors at idle speed.
- Checking work on the workpiece.
- Preservation and painting of scissors.
Additional work:
1. Replacing the clutch-brake 2. Replacing the gears of the gearbox 3. Manufacturing the electrical cabinet 4. Manufacturing the back stop 5. Installing new knives
The final stage will be the protective painting of guillotine shears, their running-in and testing of the equipment in action.
Entrust major repairs and maintenance of guillotines to professionals!
ozkpm.ru
Drawing of a guillotine shears knife 16 x 60 x 540
Knife for guillotine shears NA3121-11-418
- Knives must be made of steel grades 5ХВ2С, 6ХВ2С and 6ХС according to GOST 5950-73
- Knife hardness - HRC 54 ... 58
- Surface flatness tolerance B - no more than 0.1 mm over a length of 100 mm
- Tolerance field of dimensions s a B of a set of knives - according to h11
- The permissible difference in the sizes of the set knives at the junction is no more than 0.03 mm
- H14; h14; ±IT14/2
- Weight 4.08 kg
- The following markings must be applied to the knife: trademark of the manufacturer, designation of the knife, quality control department mark, code (number) of the kit (for composite knives).
