Hacksaw machines

Hacksaw cutting machines of models 8725, 8725AM, 8725AM-300 are designed to perform the technological operation of cutting and cutting sectional, ferrous and non-ferrous metal into dimensional blanks of a given length. The hacksaw machine or mechanical hacksaw supplied by the PromStroyMash plant allows cutting blanks at an angle of 45 to 90 degrees. The cutting tool is a hacksaw blade, for 8725 machines the blade size is 400x40x2, 8725AM 450x40x2, 8725AM-300 600x50x2.5. The dimensions of the cut blanks of round rolled products are limited by the dimensions of the saw frame, for machines of the 8725, 8725AM model it is 250 mm, 8725AM-300 respectively 300 mm. When cutting with hacksaw machines, the cutting size is 2-3.5 mm.

To expand the technological capabilities of hacksaw machines, it is possible to equip the machines with devices for batch cutting, roller tables for feeding long workpieces to the cutting zone, and roll-back trolleys for collecting and transporting cut-to-length workpieces. Hacksaw cutting machines are compact and at the same time rigid and precise devices. The bed of the 8725 and 8725AM machines is cast from cast iron grade SCH-20, the hydraulic pump for raising and lowering the saw frame has an original design, the bed of the 8725AM-300 machine is welded, the saw frame has an arched shape, made of cast iron SCH-20 to ensure cutting accuracy. A significant drawback of mechanical cutting machines is the presence of idle (reverse) strokes of the saw frame during the cutting process. Limited overall dimensions of the cross-section of the cut workpieces. Productivity is 3-4 times lower than that of band saws. Cutting machines are recommended for use in UHL-4 climate conditions according to GOST 15150, and can be manufactured for use in T-4, TV-4, TS-4, TM4 climate conditions according to a separate technical specification. Hacksaw machines are used in procurement and repair areas of various enterprises as reliable and popular equipment.

Features and description of machines

The functionality of the design of hacksaw cutting machines allows cutting metals in single and mass production in procurement and auxiliary production facilities of mechanical engineering enterprises and procurement areas.

Advantages of hacksaw machines over other cutting methods:

• Low operating costs at optimum cutting speed. Speed ​​up to 40 m/min, a good result for metal-cutting machines. The saw blade feed speed is adjusted in steps.
• The presence of a simple in design, but at the same time, effective vice. The workpiece cut with a hacksaw machine manually or with a roller table is placed in the cutting zone. Getting an industrial injury when working on hacksaw machines is completely excluded.
• The fastest possible readjustment of the vice for a certain cutting angle
• Reliable and with an excellent resource design of hacksaw machines.
• Excellent cutting accuracy. The cutting mode setting can be selected as quickly as possible depending on the diameter and material of the workpiece. independently.
• The cutting process and the return stroke with a return to the starting point are performed using a hydraulic drive. The rigidity of the feed and movement mechanisms of the saw frame allows to reduce the drift of the hacksaw blade, increasing the accuracy and quality of cutting.

All parts of the hacksaw cut-off machine are installed in the frame, which has a box-shaped cast form for the 8725, 8725AM models, welded for the 8725AM-300 model. The frame has an internal cavity in which there is a coolant tank and a pump for supplying coolant is installed.

The workpiece is cut with a hacksaw blade, the reciprocating movements of the saw frame with feed using a hydraulic pump allow for quick and efficient cutting. The hacksaw blade of the cutting machine is driven by a crankshaft that transmits rotation through gears from an electric motor.

The saw frame is raised and lowered using a hydraulic pump for the 8725, 8725AM machines and a hydraulic cylinder for the 8725AM-300 machine. The saw frame is pivotally mounted on the frame bracket, thus ensuring the movement of the saw relative to the workpiece during cutting, i.e., the working feed. Cutting is performed with a movement amplitude (saw frame stroke) of 160 mm and a speed of 85 to 110 cycles per minute for the 8725AM machine. At the end of cutting, when the limit switch is triggered, the saw frame returns to its original position automatically.

If it is necessary to saw the workpiece at an angle of up to 45 degrees, the hacksaw machine can be equipped with a rotary vice, devices for batch cutting and a roller table for cutting long workpieces at an additional cost, increasing the productivity of the machine.

The frame of the 8725, 8725AM machines, cast from gray cast iron SCH-20, is rigid and stable, designed for significant loads that occur when working with heavy workpieces. The frame consists of a base with a work table, a crank assembly, a saw sleeve and a frame on which the workpiece and saw blade are installed. The workpiece to be cut is installed on the machine table and clamped in a vice, which includes a set of pads for a specific profile. The design of the machine provides the ability to turn the workpiece and cut at an angle of up to 45°.

Main units of the hacksaw cutting machine 8725, 8725AM

Electromechanical drive of the machine

The asynchronous electric motor AIR is installed on the motor plate, the plate is fixed to the bed through a bracket. A replaceable pulley is installed on the electric motor, transmitting the rotation of the engine to the opposite pulley, the pulley is located on the same axis with a helical gear model 10 with 26 teeth, this gear is engaged with a gear with 145 teeth, which is mounted on the crankshaft key. The gears and pulleys of the drive are covered with a fence. The operation of the machine is controlled through a control cabinet installed on the machine. When the saw arm is raised to its upper position, the limit switch is triggered and automatically switches off the engine. A screw is installed on the sub-motor plate, which serves to tension the V-belt drive belts.

Bed

The bed has a box shape, cast from gray cast iron with reinforcing ribs along the perimeter. The base of the bed is simultaneously a container for coolant and a reservoir for hydraulic pump oil for the 8725 and 8725AM machines. All machine components are installed on the bed.

Cast iron base, stand

The crank mechanism is mounted in a cast iron stand. The stand is located on the rear side in the upper part of the bed. The crankshaft bearings and bronze bushings of the saw sleeve axis are mounted on the cast iron stand. The electrical cabinet is located on the rear side of the stand. The sleeve support is fixed to the pin on the inner side of the stand.

Saw sleeve

Moving on the axis mounted on the cast iron base, the saw sleeve has dovetail guides on its lower surface, along which the saw frame moves, and an adjusting wedge compensating for the gap between the saw sleeve and the saw frame. By means of a rod and two hinges, the sleeve is connected to the piston rod of the hydraulic drive working cylinder, which controls the movement of the sleeve.

Saw frame

The saw frame is installed in the guides of the saw sleeve and moves along them with a reciprocating motion from the crank shaft, to which it is connected by a connecting rod. The hacksaw blade is put on one edge through a hole on a fixed bar, a pin, and with the other hole on the axis of the movable bar and is pressed by the bars. The tension of the hacksaw blade is carried out by a screw.

Clamping vice

To install the workpiece to be cut, the cutting machine is equipped with special clamps with flat ribbed bars. The workpiece is clamped using a screw and a stop.

Stop for cutting measured workpieces

When cutting workpieces of a certain, specified length, a stop is used, which can be set in the desired position using a scale applied to the stop.

Main units of the hacksaw cutting machine 8725AM-300

Electromechanical drive of the machine

The asynchronous electric motor AIR is installed on the plate, the plate is fixed to the bed through a bracket. The electric motor has a replaceable pulley that transmits the engine rotation via V-belts to a two-stage gearbox, then to an eccentric shaft that transmits reciprocating motion to the saw frame with a 600x50x2.5 hacksaw blade installed on it via a movable connecting rod. The saw frame is lowered and raised automatically by means of a hydraulic distributor and a cylinder. All movable rotating elements of the cutting machine drive are covered with a guard fixed to the frame. The machine is controlled via a control cabinet installed on the machine. When the saw sleeve is raised to its upper position, the limit switch is triggered and automatically turns off the engine.

Frame

The frame has a box shape, cast from gray cast iron with reinforcing ribs along the perimeter. The base of the frame is simultaneously a container for coolant and an electric pump. All machine components are installed on the frame. When cutting workpieces longer than 350 mm, it is necessary to install a roller table to support the workpiece during the cutting process to prevent injury.

Saw frame

The saw frame is installed in the guides of the bed and moves along them back and forth - with a reciprocating motion from the crank disk, to which it is connected by a connecting rod. The hacksaw blade is put on one edge through a hole on a fixed fixed bar, with a pin, and on the axis of the movable bar with the other hole and is pressed by the bars. The hacksaw blade is installed with the cutting direction from the electromechanical drive, a weakly tensioned blade leads to an incorrect cut, the correct tension force is 10-12 kN.

Clamping vice

The vice consists of a movable and fixed strips, with the help of a handle, screw and nut the movable strip moves towards the movable one, clamping the workpiece. The vice allows clamping workpieces with a diameter of 25...300 mm.

Stop for cutting measured workpieces

When cutting workpieces of the required, specified length, a stop is used, which can be set in the desired position using the scale applied to the stop.

Warranty service

Since hacksaw cutting machines belong to the category of machines that require maintenance by qualified specialists, when purchasing, we recommend using the services of the plant's service specialists. During further operation of the machine, maintenance must be carried out in accordance with the requirements set out in the operating manual. Plant guarantees the machine's compliance with TU-3817-006-69398252-2015, undertakes to eliminate all breakdowns free of charge during the warranty period, provided that the consumer complies with the operating conditions.