Semi-automatic abrasive cutting machine

The 8G240 abrasive cutting machine is designed for cutting ferrous metals, carbon, structural, stainless and heat-resistant steels, various profiles with an abrasive wheel, both at a right angle and at any other angle up to 45º to the workpiece axis by turning the spindle head in a horizontal plane. During cutting, the workpieces are cold and do not require preheating. The machine cuts round and section rolled products at a right angle and at an angle of up to 45º. The cutting angle is adjusted by turning the spindle head in a horizontal plane to the workpiece axis. Cutting at a right angle is performed along the stop with markings, at an angle along the markings, without a stop. Cutting wheels with a diameter of 300, 400 mm are used for cutting on the abrasive cutting machine. The height of the circles is selected individually depending on the material being cut and is 2, 3, 4 mm. The accuracy class of the machine according to TU3828-001-66656357-2021-N.

The welded frame of the 8G240 model machine has a box-shaped form. The machines in serial factory design are intended for use in the placement category UHL-4 according to GOST 15150, upon request and according to a separate technical assignment, a semi-automatic machine in the factory conditions of the PromStroyMash plant can be manufactured in a complete set for use in climate zones T-4, TV-4, TM-4, OM-4.

Features and description of the machine

The design and technical execution of the abrasive cutting machine model 8G240 and its modifications allows for semi-automatic cutting with an abrasive wheel (with the selection of different speeds and prisms) of various workpieces (rod, pipe, rolled products) at a right angle and up to 45º. The machine has an electromechanical spindle rotation drive.

The machine rotation drive in the horizontal plane is carried out through the worm gear housing, in which the worm gear pair is mounted. The gearbox is designed to rotate and precisely position the spindle head with a fixed abrasive wheel to the workpiece being cut. A safety clutch with an adjustable toothed washer is installed on the output shaft of the gearbox.

The feed mechanism for the cut-off circle is a hydraulic cylinder, the rod of which is connected to the base of the spindle head, and the body to the machine bed. During operation, the hydraulic station of the machine controls the cylinder rod and advances or withdraws the abrasive wheel relative to the workpiece. The mechanism for clamping the workpiece in the cutting mode consists of a clamping prism connected by rods to the working hydraulic cylinder of the clamp, located inside the bed. The hydraulic station for driving the working cylinders is installed separately from the machine and is connected using high-pressure hoses. Cutting of workpieces on the abrasive cutting machine 8G240 is carried out by automatic feeding of the saw blade to the workpiece, clamped in the prisms of the machine along the stop.

Principle of operation of the machine

Work on the machine consists of the following operations:

• installation of the workpiece on the prisms
• advancement of the workpiece to the stop
• clamping of the workpiece
• lowering of the abrasive wheel onto the workpiece
• automatic return of the saw wheel to the initial upper position
• unclamping of the workpiece

Optimal cutting modes should be selected taking into account the specific material and profile of the workpiece. The cutting mode depends on the characteristics of the abrasive wheel (grain size, hardness, grade of abrasive material), the mode is selected empirically by the machine operator observing safety precautions, working in PERSONAL PROTECTIVE EQUIPMENT and carefully reading the operating manual for this machine.

The workpiece is placed on the machine prism, with the other end on an adjustable stand, roller table. The handle located on the front of the machine is used to adjust the size of the workpiece, the feed rate of the saw wheel is regulated by the flow regulator. In the semi-automatic mode of operation of the abrasive cutting machine model 8G240, the workpiece is clamped, cut, the abrasive wheel is removed from the cutting zone and the workpiece is unclamped, while the cut part of the workpiece is manually advanced by the supplied material.

Main units of the semi-automatic abrasive cutting machine

The following units are installed and mounted on the machine frame:

• spindle unit
• guards
• spindle lift cylinder
• wheel wear compensation mechanism
• wheel rotation reducer
• reverse sensor
• control panel
• hydraulic power station
• frame machine
• electric cabinet

Bed

The bed of the abrasive cutting machine model 8G240 is cast from gray cast iron grade SCH-20, and 8G240.01 is welded from metal. The shape of the beds is box-shaped; in the upper part, a rotary body with a bracket with an installed spindle head is installed on the sleeve body; the working cylinder of the clamp is located in the cavity of the beds. The hydraulic cylinder of the working stroke, made in the form of a rack, engages with the gear.

Drive reducer

The worm gear is designed to rotate the spindle at a certain degree to the workpiece being cut. The spindle head is rotated to a certain angle by a handle on a scale, after selecting a given angle, the table is fixed by moving a split conical washer.

Guards

Protective guards of the abrasive cutting machine are designed to protect the operator from abrasive and dust from the workpiece being cut. The guard is a cast iron body in the front part of which a control panel is installed. In the rear welded body of another guard there is an opening for connecting an aspiration device. The welded body has a groove on one side for moving the spindle, on the other a door for changing the abrasive wheel, in the lower part of the guard there is a sludge collector that must be cleaned at least once per shift.

Spindle

It is a cast iron body, in the design of which guides are placed for placing the motor plate of the electric motor. The electric motor is driven to the spindle by a belt transmission. The cutting speed is changed by changing the pulleys on the electric motor shaft or according to the technical specifications using a frequency converter. The machine is equipped with a pulley as standard to obtain a cut of V=63 m/s for a circle with a diameter of 400 mm. The spindle rotates using high-precision radial thrust bearings installed in the housing. A cutting wheel is attached to the end of the spindle using flanges and a nut.

Wear compensation unit for the wheel

The unit is designed to constantly monitor the degree of wear of the wheel, maintaining a constant gap of the abrasive wheel above the cut workpiece. It consists of a system of petals mounted on a bracket and two contactless sensors. As the abrasive wheel wears out, the spindle return sensor is triggered, which is indicated by a light indicator located on the control panel.

Hydraulic station

The hydraulic drive of the abrasive cutting machine model 8G240 ensures the working stroke of the spindle, clamping and unclamping of the workpiece. The hydraulic system consists of 2 working cylinders, high-pressure hoses, a flow regulator and the hydraulic station itself, located next to the machine. The hydraulic, electrical and kinematic diagram of the machine provides for the operation of the machine in semi-automatic and setup modes.

Additional options

According to the customer's technical specifications, the 8G240 abrasive cutting machine can be equipped with the following units and parts:

• cooling bath
• cyclone filtration unit
• driven roller conveyor
• various prisms for a specific material profile
• various pulleys for a specific diameter of the abrasive wheel

The 8G240 machine is shipped in partially disassembled and requires additional assembly in a regular place. Additional assembly is required for the hydraulic hoses from the machine to the hydraulic unit, as well as the electric wires going to the hydraulic unit.

The abrasive cutting machine model 8G240 is currently the most effective in terms of economic costs per unit of cut workpiece compared to other cutting methods. When purchasing and further operating the machine, we recommend using the services of the manufacturer's service specialists. During further service, the machine must be maintained in accordance with the requirements set out in the operating manual.

The abrasive cutting machine model 8G240 is a product serially manufactured by the plant, the machine is certified and meets all safety requirements.