NP-103A

Hydraulic function of the NP-103A pump

The NP-103A works as a high-pressure hydraulic power unit. As the shaft rotates, the axial piston group draws working fluid from the inlet line and delivers it to the pressure line. The pump has a working displacement of 32 cm³ per revolution and is designed for nominal pressure around 190 kgf/cm², with maximum pressure up to 210 ±5 kgf/cm². This pressure range is typical for aircraft hydraulic systems where compact size, high output and stable pressure are required.

Automatic flow regulation in NP-103A

A key feature of the NP-103A is variable displacement with automatic pressure regulation. The internal regulator changes the plunger stroke depending on hydraulic system demand. When demand increases, the pump increases delivery; when pressure reaches the set level, the regulator reduces output to avoid unnecessary loading. This design helps maintain stable pressure, reduce heating and limit excess power consumption compared with a pump that constantly works at full delivery.

Installation of NP-103A in onboard hydraulic systems

The NP-103A is installed as part of aircraft or specialized hydraulic systems where high-pressure fluid supply is required. The pump is mechanically driven through its shaft and works together with the aircraft hydraulic tank, inlet boost line, pressure line and drain circuit. For correct operation, the inlet must receive positive pressure, normally within the specified range. This is important because insufficient inlet pressure can cause cavitation, noise, unstable delivery and accelerated wear of the axial piston group.

Working fluid and temperature conditions for NP-103A

The NP-103A is intended for aviation hydraulic oil, such as AMG-10 type fluid or an approved equivalent, depending on the aircraft hydraulic system documentation. The pump is designed to work over a wide temperature range, from −60 to +100 °C, with short-term operation up to +120 °C according to supplied data. Oil cleanliness, viscosity and inlet pressure are critical for serviceability. Contaminated or overheated hydraulic fluid can affect the regulator, piston group, seals and bearing areas.

NP-103A in aircraft application

The NP-103A is used in aviation equipment and specialized hydraulic systems that require a compact high-pressure pump with automatic regulation. It is associated with aircraft hydraulic architectures where pressure must be supplied to actuators, control drives, landing gear mechanisms, braking systems or other hydraulic consumers depending on the aircraft configuration. The exact installation and compatibility must be checked by aircraft type, hydraulic system diagram, direction of rotation and approved maintenance documentation.

Design and connection points of NP-103A

The NP-103A has a compact cylindrical body with a drive shaft, mounting flange and hydraulic connection ports. The main hydraulic connections include an inlet line, high-pressure outlet line and drain line for internal leakage return. The drain is important because internal leakage lubricates and cools working parts and must be returned to the hydraulic tank without excessive back pressure. During maintenance, technicians should check the flange, shaft, ports, seals, regulator operation and signs of leakage or contamination.

Supply and documentation for NP-103A

For supply or replacement, the pump should be requested by its full designation: NP-103A / НП-103А. Because this is a regulated high-pressure hydraulic pump, documentation and testing are important. Before installation, the unit should be checked for displacement, flow rate, pressure regulation, maximum pressure, inlet pressure requirement, leakage, drain condition and drive interface. Product passport and operational documentation should be requested whenever the unit is intended for aircraft installation.