Recommend Products
Contact Us
| Email: | info@sanchangpump.net |
| Hotline： | +86 181 4266 2779 |
| +86 193 1300 1794 | |
|
Wechat： |
+86 181 4266 2779 |
|
WhatsApp: |
+86 181 4266 2779 |
| Address： | No.517,Xiangfu Road |
| Yuhua District, | |
| Changsha City | |
| Hunan Province, P.R.C |
Parallel Double-inlet Self-balancing Multistage Pump
Classification:
BB4 Self-balancing Multistage Pump
Key words:
Head Range: 80–500 m (adjustable by changing impeller stages)
Rotational Speed: 1480 r/min / 2980 r/min
Medium Temperature: ≤80℃ for clean water; ≤105℃ for hot water
Wetted Parts Material: Cast iron HT250, Ductile iron QT600, Cast steel, Stainless steel 304 / 316
Hotline:
- Product Description
- Performance Parameter
- Installation Drawings
- Installation And Use
- Faults And Solutions
-
- Commodity name: Parallel Double-inlet Self-balancing Multistage Pump
Flow Range: 50–2,700 m³/h <br/> Head Range: 80–500 m (adjustable by changing impeller stages) <br/> Rotational Speed: 1480 r/min / 2980 r/min <br/> Medium Temperature: ≤80℃ for clean water; ≤105℃ for hot water <br/> Wetted Parts Material: Cast iron HT250, Ductile iron QT600, Cast steel, Stainless steel 304 / 316
I. Product Overview
The parallel double-inlet self-balancing multistage centrifugal pump adopts a dual-suction design with symmetrically arranged impeller rotor parts. Two independent flow channels converge at the discharge casing before fluid discharge to realize parallel flow path layout. This design completely balances the axial thrust acting on internal rotor components, featuring compact structure, zero external leakage, high efficiency and stable operation with wide application scope, becoming an optimized new product of self-balancing horizontal multistage centrifugal pump family.
Characterized by large rated flow and high head, this pump serves as an effective supplement to single-stage double-suction horizontal centrifugal pumps and conventional self-balancing horizontal multistage pumps. Widely applied in municipal water supply projects, hydraulic engineering, petrochemical industry and other working conditions requiring large flow and high head, it can replace the traditional multi-pump serial water supply mode using single-stage double-suction pumps and finish water delivery by a single unit, greatly cutting project investment as well as equipment operation and maintenance costs.
II. Product Features
1. Separate suction flanges are arranged on both pump ends with an integrated discharge connection at the middle section. Symmetric reversely installed impellers counteract total axial thrust via hydraulic action inherently. Balancing discs and related auxiliary fittings used on conventional multistage pumps are eliminated to upgrade the overall pump structure.
2. The bilateral suction layout removes balance return pipelines, fundamentally avoiding volumetric loss induced by circulated balancing fluid and reducing useless power consumption.
3. High-pressure liquid is confined inside middle pump casings, while shaft seals at both ends operate continuously under low-pressure environment, greatly improving working conditions for mechanical seals and drastically cutting leakage failure rate.
4. Omission of consumable middle casing throttling sleeves lowers later maintenance and replacement cost and reduces hydraulic loss caused by clearance leakage, thus lifting overall pump efficiency.
5. Side-inlet semi-spiral suction chambers are fitted at suction ends to stabilize incoming flow, restrain vortex formation and optimize fluid flow into impellers. The pump obtains outstanding anti-cavitation performance and is suitable for low-level suction working conditions.
III. Model Description
Example: MDP360-60×5 double-inlet self-balancing multistage pump:
MD —— Mine-use abrasion-resistant multistage centrifugal pump
P —— Self-balancing construction
360 —— Design rated flow: 360 m³/h
60 —— Single-stage design head: 60 m
5 —— Total impeller stages: 5 stages
IV. Structural Description
This pump mainly consists of pump casing assembly, rotor assembly, bearing assembly, sealing assembly, common base for inlet/outlet piping and coupling. Details of each component are specified below:
1. Pump Casing Assembly: Composed of suction casings, middle casings, discharge casing and diffusers, integrally cast from high-grade cast iron, ductile iron or wear-resistant cast steel with excellent pressure resistance, corrosion resistance and deformation resistance. The sectional design ensures reliable sealing; impeller stages can be added or removed flexibly to meet different head requirements for wide adaptability.
2. Rotor Assembly: Core working component made up of pump shaft, symmetric multistage impellers, shaft sleeves and positioning sleeves. Impellers on left and right sides rotate oppositely with identical quantity; their generated axial forces fully counteract each other during operation. The rotor keeps centered without axial shifting or eccentric wear, effectively prolonging service life of bearings and impellers.
3. Bearing Assembly: Equipped with high-precision rolling bearings or plain bearings available with grease lubrication or oil bath lubrication. Featuring low friction loss and good heat dissipation, it supports long-term continuous high-speed operation with easy maintenance and low failure rate.
4. Sealing Assembly: Configured with mechanical seal or packing seal for stable sealing to prevent medium leakage outward and air infiltration inward. Wear-resistant and high-temperature resistant sealing materials are optional according to medium temperature, working pressure and impurity content to match various working conditions.
5. Base & Transmission Assembly: Integral steel base features excellent vibration damping and stable installation. The coupling connects pump and motor for high-efficiency power transmission and smooth running to avoid eccentric vibration.
V. Applicable Operating Conditions
Thanks to advantages of large flow, high head, stable performance, superior anti-cavitation capacity and low maintenance cost, this pump is applicable for conveying clean water and liquid containing tiny solid particles:
1. Mining Industry: Underground drainage for mines with massive water inflow, pit water removal and clean tailings transportation. MDSP mining-type pumps are available with MA coal safety certification for underground explosion-proof continuous operation.
2. Municipal Water Supply: High-rise building water supply, long-distance mountain water conveyance, raw water boosting for waterworks, pipeline supplementary water replenishment and reservoir water lifting projects.
3. Infrastructure Construction: Dewatering for tunnels, subways, foundation pits and bridge construction sites, suitable for rapid large-flow drainage and suction under variable liquid levels.
4. Industrial Production: Industrial boiler feed water, clean water circulation for chemical workshops, low-pressure water injection for oilfields, production water boosting and circulating water for HVAC systems.
5. Other Applications: Large-area farmland irrigation, hydraulic water lifting, dock drainage and all 24-hour continuous pressurized water delivery projects.
Applicable Medium: Normal-temperature clean water, purified industrial water and water with trace silt impurities; standard medium temperature: 0～80℃, customized hot-water version can reach 105℃.
VI. Standard Supply Scope:
Complete set includes main pump unit with preassembled rotor, bearing and sealing assemblies, shared steel base, coupling plus safety guard, GB-standard matching motor, anchor bolts, inlet/outlet flange gaskets and other accessories, as well as full technical documents including product certificate and operation manual. Valves, instruments, electric control cabinets and spare wear parts are supplied optionally upon customers’ requirements.
Hunan Sanchang Pump Industry Co., Ltd. provides customized production for this pump series. Your inquiry is welcome.
-
Flow Range: 50–2,700 m³/h
Head Range: 80–500 m (adjustable by changing impeller stages)
Rotational Speed: 1480 r/min / 2980 r/min
Medium Temperature: ≤80℃ for clean water; ≤105℃ for hot water
Wetted Parts Material: Cast iron HT250, Ductile iron QT600, Cast steel, Stainless steel 304 / 316
-
Key Points for Installation & Operation of Parallel Double‑Inlet Self‑Balancing Multistage Pump
Ⅰ. Installation Guidelines
1. Foundation Leveling: Lay the base horizontally and compact with shim plates; tighten anchor bolts fully to avoid tilt and vibration.
2. Coupling Alignment: Align the coupling between pump and motor. Rotate the rotor by hand smoothly without jamming or abnormal noise.
3. Double Suction Piping (Critical Item): The two suction pipelines on both sides shall adopt identical pipe size, length and flow resistance to achieve uniform inflow and ensure effective self‑balancing; pipeline weight shall not be borne by pump flanges.
4. Parallel Discharge Piping: Each pump discharge shall be equipped with gate valve, check valve and flexible connector to prevent reverse backflow and pump reverse rotation after shutdown.
5. Preserve Original Balancing Structure: Do not block or modify the factory‑fitted balance pipe and balancing structure of the pump.
Ⅱ. Startup Operation
1. Pre‑start preparation: Fully open both suction valves, fill the pump with medium and vent all trapped air; dry running is strictly prohibited.
2. Single pump startup: Start the pump with discharge valve closed; gradually open the valve after stable operation to reach rated working condition.
3. Multiple pumps in parallel (Key): Never start all pumps simultaneously; start the next unit only after the preceding pump runs steadily to prevent water hammer and motor overload.
Ⅲ. Operation Specifications
1. Operating pressure and motor current of all parallel pumps shall be roughly consistent with minor deviation only.
2. Long‑term low‑flow or dead‑head operation is forbidden, as it may damage self‑balancing structure and accelerate bearing wear.
3. No severe vibration or abnormal noise during operation; bearing temperature shall not exceed 75℃, and slight dripping of mechanical seal is acceptable.
Ⅳ. Shutdown Procedure
1. Gradually close the discharge valve before cutting off power to stop the pump.
2. Drain all residual liquid inside the pump for long‑term shutdown to avoid freezing and rusting.
Ⅴ. Common Faults & Causes
1. Excessive vibration and overheating: Uneven bilateral suction flow, air ingress or misaligned coupling.
2. Backflow and insufficient discharge pressure for parallel units: Damaged check valve or mismatched pump head parameters.
3. Failed self‑balancing and fast component abrasion: Unbalanced inflow between double suction sides or blocked pipelines.
-
Troubleshooting & Solutions for Parallel Double-Inlet Self-Balancing Multistage Pump
1. Excessive pump vibration and overheated bearings
Check both suction pipelines for blockage and air leakage to realize uniform bilateral inflow; realign the concentricity between pump and motor, tighten anchor bolts to eliminate unit looseness and mechanical resonance.
2. Backflow and insufficient discharge pressure under parallel operation
Repair or replace faulty outlet check valves; verify model and head parameters of parallel pumps to unify operating conditions, fine-tune outlet valves for matched working performance of all pumps.
3. Failed self-balancing and rapid component wear
Remove debris and unclog double suction pipelines, adjust pipe fittings to keep identical flow resistance on both sides; confirm balance pipes are unblocked and unaltered, restore original factory balancing structure.
4. No water delivery or unstable outflow
Refill pump casing and fully evacuate entrapped air; confirm full opening of suction valves and airtight piping; inspect inlet & outlet lines for clogging and clean strainers and pipeline contaminants.
5. Severe leakage at mechanical seal
Prevent pipeline load from pressing pump flanges and install pipe supports; avoid dry running and cavitation operation; replace mechanical seal promptly when leakage exceeds permissible limit.
Previous Page
Next Page
Customer Case
Product Consulting
If you are interested in our products, please leave your email, we will contact you as soon as possible, thank you!
Hunan Sanchang Pump Co., Ltd.
| Email: | info@sanchangpump.net |
| Hotline: | +86 181 4266 2779 |
| +86 193 1300 1794 | |
| Mobile/Wechat/WhatsApp: | +86 181 4266 2779 |
| Address: | No.517,Xiangfu Road, Yuhua |
| District, Changsha City | |
| Hunan Province, P.R.C |
