Gear-type pumps SH, NMSH, NMSHF, NMSHG (oil products)

Gear pumps of SH, NMSH, NMSHF, NMSHG type and electric pump units on their base are intended for pumping petroleum products (oil, OMTI oil, diesel fuel, petroleum, residual fuel oil) and other liquids possessing lubricating ability (magnetic varnish, paints), including easy-to solidify ones (bitumen, pitch, rubberax and so on – NMSHG pumps with heating) without mechanical impurities and which do not promote corrosion of pump body members.

The viscosity of the pumped liquids is from 0,018・10-4 up to 22,00・10-4 m2/s (1,08…300°E), temperature up to +70°С (we can customize the pump to temperatures up to 250°С). The lower limit of viscosity is restricted by lubricating power of the pumped liquid, the upper limit – by power of the electric motor and suction capacity of the pump. While placing purchase order do not fail to agree viscosity limits and working temperature of the pumped liquid.

Pumps and units are related to the items of aspect 1 (repairable) as per GOST 27.003-9.

For the orders of Russian Maritime Register of Shipping (RMRS), the pumps (units) are produced in climatic version OM, location category 2, 5 GOST 15150-69, and may be installed on the marine ships with unlimited region of navigation, as well as in the boiler and engine rooms of the ships having the following automation mark A1 and A2 within the RMRS classification of ships.

By the Client’s request, special pump embodiments for servicing in explosion-and-fire hazard productions of classes V-1а, V-1b, V-1g, V-II as per Electric Installation Code may be delivered.

Electric pump unit consists of the gear pump and electric motor, which are mounted:

• for SH, NMSH, NMSHG pumps – on the common plate (frame) and the coupling protected with housing
• for NMSHF pumps – with the help of the connecting piece (welded or cast one) and the coupling

At the Client's request the pump may be delivered in assembly with the coupling or without the coupling, less the electric motor and plate (frame) or with no connecting piece.

As to the principle of operation the gear pump is a positive displacement machine. In the course of rotation of the driving and driven rotors a vacuum is created at the inlet side, as a result the liquid under the atmospheric pressure fills the hollows between gear teeth and moves within them from the suction cavity into the delivery one. At the outlet, when the teeth are in engagement, the liquid is extruded into the system

The pump consists of the following main parts and subassemblies: working mechanism, casing with rear cover and upright, safety and relief valves, end-face seal.

End-face seals may be of both productions: imported seals and own-produced seals. At the Client's request the stuffing box is possible (maximum allowable pressure of the medium of 2,0 МPа (20 kgf/сm²), for OMTI oil - is not supplied).

Working mechanism consists of two rotors – the driving and driven rotors and the bushings (plain bearings).

At the butt-end the casing is closed by rear cover and upright. For NMSHG pumps the casing is closed with heating cover and front cover.

• are intended for pumping of oil products (mineral oils, mazut) diesel fuel and etc. with viscosity from 1,08 up to 300E) at the oil refining enterprises
• at the heat supply enterprises for supply of residual oil, diesel fuel in boiler installations
• for unloading/transfer of oil products on shipping terminals
• for ensuring supply of greasing liquids in lubrication systems of the high-loaded cars and mechanisms (turbine, rolling mills, etc.)
• in stationary installations, bitumen concrete plants and mobile bitumen carriers (pump NMSHG 120-10 – is analogous to DS-125)

• simple design provides high reliability of pump
• casing-gears clearance adjusting device provides high pump efficiency
• virtually no need in maintenance
• compact size s for use in confined space
• single mechanical seals made of different materials (no need in barrier liquid supply)
• true for the pumps NMSHG 120-10 (DS-125 analog) – by technical characteristics and overall & mounting dimensions the said pump is analogous to asphalt pump DS-125, it has reversible direction of rotation (entry from either direction)

For example SH 40-4T-19,5/4B-1 U3 TU 26-06-1087-84, where :

• SH – designation of the pump type: SH – gear pump, NMSH – gear oil foot-mounted pump
• NMSHF – gear oil flange mounted pump, NMSHG – gear oil pump with heating (cooling) of the casing;
• 40 – capacity of the pump in litres per 100 rev.
• 4 – maximum pressure of the pump, kgf/сm²
• T – pump embodiment: Т – up to t=250°С, 1 – for OMTI oil, 2 – single end-face seal with additional seal, 3 – with stuffing box, 4 – for a pressure of 40 kgf/сm²
• 19,5 – capacity of the pump when coupled with motor, m²/h
• 4 – outlet pressure of the pump when coupled with motor, kgf/сm²
• B – conventional designation of the flow passage material: without designation – cast iron, B – bronze, Yu – aluminium and its alloys, К – stainless steel
• 1 – unit modification acc. to drive type (Rp – variable drive)
• U3 – climatic version and location category as per GOST15150-69