ISU-152-2

ISU-152-2 had the same layout as all other serial Soviet self-propelled guns of that time (with the exception of SU-76 ). The fully armored hull was divided into two parts. The crew, guns and ammunition were located in front in the armored cabin, which combined the fighting compartment and the control compartment. The engine and transmission were installed in the stern of the car.

Armored hull and wheelhouse

The armored body of the self-propelled gun was welded from rolled armored plates 90, 75, 60, 30 and 20 mm thick; its frontal part of the hull was an armored cast. Armor protection differentiated , protivosnaryadny. Armor plate felling installed at rational angles. The main armament - the 152-mm BL-10 gun - was mounted in a frame-type installation to the right of the axial line of the machine. Gun recoil devices were protected by a fixed cast armored casing and a movable cast armored.

Three crew members were located to the left of the gun: in front of the driver, then the gunner, and behind - the loader. The machine commander and the castle were to the right of the gun. The crew embarked and exited through a rectangular double-wing hatch at the junction of the roof and rear sheets of the armored cabin and through a round hatch to the right of the gun. The round hatch to the left of the gun was not intended for the crew to enter and exit; it was required to bring out the extension of the panoramic sight. The hull also had a bottom hatch for emergency escape by the crew of self-propelled guns and a number of small hatches for loading the ammunition, access to the necks of the fuel tanks, other components and assemblies of the machine.

Armament

The main weapon of the ISU-152-2 was the BL-10 ( Bolshevik - Leningradsky ) gun of 152.4 mm caliber with a semi-automatic wedge bolt and a muzzle brake of the original design. The ballistics of the gun was similar to the previous version of the BL-8. The gun was mounted in a frame on the frontal armor plate of the cabin and had vertical aiming angles from −2 ° 30 ′ to + 17 ° 30 ′, the horizontal aiming sector was 9 ° 30 ′ (2 ° 30 ′ to the left and 7 ° to the right). Balancing the swinging part of the gun in the trunnions was carried out by attaching weights to the fixed part of the cannon fence. The gun was equipped with a device for purging the barrel with compressed air after firing . The height of the line of fire was 1655 mm, the range of a direct shot was 1000–1200 m for a target 2.5–3 m high, the range of a direct-fire shot was 5 km, the longest range was about 18 km. The shot was fired by electric or manual mechanical descent. Due to the imperfection of technology, as well as due to the low quality of the metal, the gun’s barrel could not stand and did not pass the tests. BL-10 was sent for revision, which did not end until the end of World War II.

The ammunition of the gun was 20 rounds of separate loading. Shells were stacked along both sides of the cabin, charges - in the same place, as well as on the bottom of the fighting compartment and on the rear wall of the cabin. The armor-piercing projectile fired from the BL-10 gun, weighing 43.5 kg, had an initial velocity of 850 m / s, which was 250 m / s higher than that of the ML-20S gun.

For self-defense, the crew had two submachine guns (submachine guns) PPSh or PPS with an ammunition load of 497 rounds (7 disks) and 25 F-1 hand grenades.

Engine

ISU-152-2 was equipped with a four-stroke V-shaped 12-cylinder diesel engine V-2-IS with a capacity of 520 liters. with. (382 kW ). The engine was started by an inertial starter with manual and electric drives or compressed air from two tanks in the fighting compartment of the machine. The electric drive of the inertial starter was an auxiliary electric motor with a power of 0.88 kW. The V-2IS diesel engine was equipped with an NK-1 high-pressure fuel pump with an RNK-1 all-mode regulator and a fuel feed corrector. To clean the air entering the engine, a Multicyclone filter was used. Also, heating devices were installed in the engine-transmission compartment to facilitate starting the engine in the cold season. They could also be used to heat the fighting compartment of the car. ISU-152-2 had three fuel tanks, two of which were located in the fighting compartment, and one in the engine-transmission. The self-propelled gun was also equipped with three external additional fuel tanks that were not connected to the fuel system of the engine.

Transmission

Self-propelled guns ISU-152-2 was equipped with a mechanical transmission , which included:

• multi-disc main clutch of dry friction of steel according to ferodo ;
• four- speed gearbox with a demultiplier (8 forward gears and 2 reverse gears);
• two onboard two-stage planetary turning gears with multi-plate locking friction clutch of dry friction “steel on steel” and belt brakes ;
• two double-row combined final drives .

Chassis

The ISU-152-2 suspension is individual torsion bar for each of the 6 solid cast gable road wheels of small diameter on each side. Opposite each track roller, the travel stops of the suspension balancers were welded to the armored hull. Driving wheels with removable cogwheels of the pinion gear were located at the rear, and the sloths were identical to the track rollers. The upper track branch was supported by three small solid casting support rollers on each side. Track tension mechanism - screw; each track consisted of 86 single ridge tracks with a width of 650 mm.

Electrical equipment

The wiring in the ISU-152-2 self-propelled guns was single-wire, the armored hull of the vehicle served as the second wire . Sources of electricity (operating voltages of 12 and 24 V) were a P-4563A generator with a 1 kW RRA-24F relay regulator and two series-connected 6-STE-128 rechargeable batteries with a total capacity of 128 Ah . Electricity consumers included:

• external and internal lighting of the machine, illumination devices for sights and scales of measuring instruments;
• external sound signal and signaling circuit from the landing to the crew of the car;
• instrumentation ( ammeter and voltmeter );
• electric trigger gun;
• communication facilities - radio station and tank intercom;
• electrician of the motor group - an electric motor of an inertial starter, a bobbin of candles for winter start of the engine, etc.

Surveillance Tools and Sights

All hatches for entry and disembarkation of the crew, as well as the hatch of the artillery panorama, had Mk IV periscope devices for observing the environment from the inside of the vehicle (only 3 pieces). The driver in battle conducted surveillance through a viewing device with a triplex, which was protected by an armored flap. This viewing device was installed in an armored cork hatch on the frontal armored plate of the cabin to the left of the gun. In a quiet environment, this cork hatch could be pushed forward, providing the driver with a more convenient direct view from his workplace.

For firing, the self-propelled gun was equipped with two gun sights - telescopic ST-10 for direct fire and Hertz panorama for firing from closed positions . The ST-10 telescopic sights were graduated for aimed shooting at a distance of up to 900 m. However, the firing range of a 152 mm gun was up to 18 km and for firing at a distance of over 900 m (both direct fire and from closed positions), the gunner had to use the second panoramic sight. To provide a view through the upper left round hatch in the cabin roof, the panoramic sight was equipped with a special extension cord. To ensure the possibility of fire in the dark, the scales of the sights had backlight devices.

Communication Tools

Communication facilities included a 10RK radio station and a TPU-4-BisF intercom for 4 subscribers.

The 10RK radio station was a set of a transmitter , a receiver, and umformers (single-arm motor generators ) for their power supply, connected to an on-board electrical network of 24 V.

From a technical point of view, 10РК was a simplex tube short-wave radio station operating in the frequency range from 3.75 to 6 MHz (respectively, wavelengths from 50 to 80 m). In the parking lot, the communication range in the telephone (voice) mode reached 20–25 km, while in traffic it decreased somewhat. A longer communication range could be obtained in telegraph mode, when information was transmitted by telegraphic key to Morse code or some other discrete coding system. Frequency stabilization was carried out by a removable quartz resonator ; there was also a smooth frequency adjustment. 10РК allowed simultaneous communication at two fixed frequencies (with the possibility of smooth tuning mentioned above); To change them, another quartz resonator of 8 pairs in the set of the radio station was used.

The tank intercom TPU-4-BisF allowed negotiating between crew members of self-propelled guns even in a very noisy environment and connecting a headset (head phones and laryngophons ) to a radio station for external communication.

• Self-propelled artillery mount
• ISU-152
• ISU-152-1

• Solyankin A.G., Pavlov M.V., Pavlov I.V., Zheltov I.G. Soviet heavy self-propelled artillery installations of 1941-1945. - M .: Exprint, 2005. - S. 48. - ISBN 5-94038-080-8 .
• Karpenko A.V. Heavy Soviet self-propelled guns // Tankmaster. - 2001. - No. 4 .

• A. Sorokin. Self-propelled gun ISU-152 (neopr.) . Armor site Chobitka Vasily . Archived on August 18, 2011.