1.Specification
Type Parameter | 3NB1300C
|
Input power rating (KW) | 956 (1300HP) |
Rated pump speed (SPM) | 120 |
Stroke (mm) | 305 |
Gear ratio | 3.81 |
Rated speed of transmission shaft (RPM) | 457 |
Max. working pressure (MPa) | 34.3 (5000PSI) |
Valve size (API) | 7# |
Max. liner diameter (mm) | φ190 |
Max. displacement (l/s) | 46.6 |
Max. liner pressure (MPa) | 18.4 (2500PSI) |
Diameter of suction pipe (mm) | 305 (12”) |
Diameter of discharge pipe (mm) | 100 (4”) |
Overall dimensions | 5010x1942x1918mm |
Weight (ton) | 23
|
2. Design features
2.1 The power end
2.1.1 The pump frame is of welded steel – plate construction. The bearinghousings of the crankshaft and the transmission shaft are made of steelcastings and are welded to the frame after rough – machined. They are stress –relieved after welded.
2.1.2 The crankshaft is a hollow steel casting.
2.1.3 The herringbone gear ring and pinion are composed of helical gears inpairs
respectively.
2.1.4 The crosshead is a one – piece casting and runs directly in the guides.
2.1.5 All the bearings, crossheads and guides are splash – lubricated. Atsuitable locations there are oil wipers and troughs provided to ensure a well –distributed lubrication.
2.1.6 The transmission shaft is equipped with single – row radial short –roller bearings.
2.1.7 The main bearings are double – row radial spherical – roller bearings.
2.1.8 The crosshead is equipped with long – roller bearings.
2.1.9 The big end of the connecting rod runs in radial roller bearing.
2.2 The fluid end
2.2.1 The fluid end is composed of three fluid modules (cylinders), each ofwhich is a
sectional and communicating construction.The suction and discharge are
accomplished by suction and dischargepipes. The suction and discharge valves are
vertically aligned with each other tominimize the volumetric clearance.
2.2.2 There is clamp connection between the piston rod and the intermediaterod, which facilitates the services of these parts.
2.2.3 The piston liner is attached to the liner seat with a buttress –threaded retainer.
2.2.4 The threaded cover of the valve box is attached to the threaded ringwith buttress threads, which facilitates the services of them. The threadedring is fastened to the fluid module with studs, which facilitates themachining and servicing of the fluid
module.
2.2.5 The taper of the valve seat is 1:6. The bottom of the seat is providedwith a shoulder to be suitable for high operating pressure
2.2.6 The piston rod conforms to SY5138-86. The piston is fastened with M39x3locknut and is lubricated and cooled by the water or the water with inhibitorsupplied by a centrifugal spray pump.
2.2.7 There are six sizes of liners with an increment of 10mm in I.D. Allthese liners are the same in O.D.
2.2.8 There are two types of liners: high-grade liner and plain liner. Thehigh – grade liner is made of carbon steel as a base metal which is casted orinserted with high – chrome alloy – steel to ensure wearability. The plainliner is made of low – carbon steel which is carburized and quenched inside toenhance the surface hardness.
2.2.9 There are suction inlets in front of and on both sides of the pump,which are connected to the suction manifold. The three suction flanges are of12”ASAB16.5-150PSI or 10”ASAB16.5-150PSI.
2.2.10 The flanges of discharge pipe andfive-way joint are of 4”API-5000PSI6B. The seal rings here are API’s R39.
2.2.11 The discharge pulsation dampener is spherical and pre – pressured. ItsMax. working pressure is 350kg/cm2, and volume is 75 litres (20 gallons). Thepulsation dampener is connected to the air filler and to the pressure gauge,using 3/4” – 14NPT and 1/4” – 18NPT respectively.
2.2.12 The suction pulsation dampener is ofrubber – hose type and pre – pressured and connected with the flanges of the12” and 10”ASAB16.5-150PSI.
2.2.13 It is advisable to equip a chargingpump during operation to improve the suction performance and raise theefficiency of the slush pump.
2.2.14 It is advisable to equip a spray pump during operation to cool thepistons and liners so as to extend their service life.
2.3 Accessories
Complete set of special tools for majorlocations of the pump will be provided along with the slush pump to facilitatethe services and replacement of expendable parts.