How to calibrate and adjust the safety relief valve on CQB pump?

Set the internal safety relief valve cracking pressure between 1.05 and 1.15 times the rated working pressure. This ensures automatic bypass during pressure surges, protecting the magnetic coupling and isolation sleeve from mechanical stress.

What are the speed reduction rules for CQB pump when handling high viscosity fluids?

Reduce pump speed as fluid viscosity increases to maintain NPSHa margins and prevent motor overload. A general rule is to reduce speed by 5-8% for every 100 cP increase in viscosity, utilizing VFDs for smooth control.

How to troubleshoot shaft seal leakage on CQB pump?

Since CQB pumps utilize full static sealing, leakage indicates isolation sleeve corrosion or magnetic coupling failure. Routine maintenance should focus on monitoring bearing temperatures and ensuring the cooling fluid level for the silicon carbide bearings is adequate.

CQB SERIES10 modelsHS: 8413.70.99

CQB Magnetic Drive Centrifugal Pump (CQB Series)

Chemical, Magnetic & Diaphragm Pumps•CQB

Flow Range: 3.2 ~ 100 m³/h
Head Range: 20 ~ 80 m
Motor Power: 1.1 ~ 30 kW
Model: CQB-32-20-125 → CQB-100-65-315
Customs HS Code: 8413.70.99

WhatsApp Quick Quote Email for Price & DrawingModel-by-Model Technical Specifications ↓

CQB Magnetic Drive Centrifugal Pump (CQB Series)

Hydraulic Principle & Internal Construction

The CQB series magnetic drive centrifugal pump eliminates traditional dynamic shaft seals by transmitting torque through a magnetic coupling across a stationary containment shell. Constructed from 304/316L stainless steel or titanium, it provides 100% leak-free containment for volatile organic compounds (VOCs), flammable solvents, toxic acids, and high-purity chemical media.

Model-by-Model Technical Specifications

Model	Inlet	Outlet	Flow (m³/h)	Head (m)	Speed (rpm)	Motor (kW)
CQB-32-20-125	DN32	DN20	3.2	20	2900	1.1
CQB-40-25-125	DN40	DN25	6.3	20	2900	2.2
CQB-40-32-160	DN40	DN32	6.3	32	2900	4
CQB-50-32-160	DN50	DN32	12.5	32	2900	5.5
CQB-50-40-200	DN50	DN40	12.5	50	2900	7.5
CQB-65-40-200	DN65	DN40	25	50	2900	11
CQB-65-50-250	DN65	DN50	25	80	2900	18.5
CQB-80-50-200	DN80	DN50	50	50	2900	15
CQB-80-65-250	DN80	DN65	50	80	2900	30
CQB-100-65-315	DN100	DN65	100	80	2900	30

Selection guidance: match your duty point to the closest model below, then confirm with our engineers. Values are rated operating points at the listed speed.

Need Complete Engineering Dimensions & Curves?

Download the official CQB series 1-page technical datasheet covering all 10 model configurations.

Media Compatibility & Viscosity / Temperature Guide

Medium	Max Viscosity (cSt)	Application Note
Flammable, Explosive & Toxic Chemical Fluids	200	Hermetic Zero-Leakage Sealless
Corrosive Acids & Alkalis (Dilute)	150	Hastelloy Isolation Shell
High-Value Volatile Chemical Solvents	100	Semiconductor Wet Chemical Etching
Precious Metals Leaching & Refining Electrolyte	120	Electronic Grade Ultra-Clean

International Benchmark & Interchange Guide

International Benchmarks

Iwaki (Japan) magnetic drive pumps
Hermetic-Pumpen (Germany) sealless pumps
Dickow / Sundyne magnetic drive pumps

Interchange Note

Sealless magnetic drive centrifugal pump. Equivalent to Iwaki MDM, Richter MNK, and Sundyne HMD Kontro magnetic drive chemical pumps for hazardous fluids.

Materials & Shaft Seal Selection Guide

Engineering metallurgy and seal selection advice for corrosiveness and temperature: CQB pump bodies are typically cast from HT250 or QT400 for non-corrosive media at ambient temperatures. For acidic or alkaline fluids, 316L stainless steel or duplex steel is mandatory. Isolation sleeves should use Hastelloy B/C for oxidizing acids and Titanium for reducing acids or seawater. While designed as sealless, fluororubber O-rings can be used as auxiliary static seals in extreme conditions to ensure long-term reliability.

Casing & Housing Materials: 304 / 316L Stainless SteelHastelloy C-276 Alloy
Rotor / Gear / Screw Elements: 316L Stainless Steel ImpellerHastelloy C-276 Impeller
Containment Shell / Isolation Sleeve: Hastelloy C-276 Containment Can / Isolation ShellCarbon-Fiber Reinforced PEEK / Composite Isolation Shell
Bearing & Bushing Materials: High-Purity Sintered Silicon Carbide (SSiC) Self-Lubricating Bearings
Shaft Sealing Options: Encapsulated PTFE / FKM Static O-Rings (Zero Leakage)

Engineering FAQ

Ensure at least 5 pipe diameters of straight run before the inlet to minimize turbulence and maintain adequate NPSHa. For high viscosity fluids, utilize low-level suction and limit flow velocity between 1.5-2.0 m/s to prevent vaporization and air entrainment.

📐 Engineering Selection Methodology

Correct pump selection starts from the fluid, not the pump. Confirm the medium name and actual viscosity at working temperature, the required flow and differential pressure or head, suction conditions (flooded or lift), and whether the fluid crystallizes, shears, contains particles or gas. Positive displacement pumps must always be protected by a relief valve or pressure bypass on the discharge line, and must never be started against a closed valve unless a bypass is fitted. For viscous duties, derate rotational speed to preserve volumetric efficiency; for crystallizing or high-freezing-point media, specify jacketed casings with steam or thermal-oil heating. Our engineers verify each enquiry against these rules before quoting.

🏭 Manufacturing & Quality Control

Castings are produced in our own foundry cluster with material certificates for each heat number. Gear profiles, screw threads and rotor lobes are hobbed, ground and wire-cut to tolerance, then assembled with matched bearing sets. Before dispatch every pump passes casing hydrostatic pressure testing, a run-in test at rated speed on an oil bench, and relief valve cracking-pressure verification; test records are archived against the pump serial number and can be supplied with the shipment.

📦 Export Packaging & Delivery

Pumps are preserved with anti-rust coating, flanges blanked, and packed in export-grade plywood cases with steel strapping for sea freight. Document packs include operating manual, performance test record, packing list and material certificates on request. Standard models ship from stock; engineered configurations typically require 15-35 days depending on casing material and seal options. Spare rotor sets, seal kits and relief valve assemblies can be quoted together with the base pump.

Typical Applications & Industry Use Cases

The media compatibility table above maps directly to real industry duties. In lubrication circuits, size the pump for continuous duty at 70-80% of rated flow to leave margin for viscosity drift as oil warms up. In chemical transfer, confirm the medium's specific gravity and whether it is shear-sensitive before fixing rotational speed. In food and sanitary service, schedule CIP cycles around the product changeover plan and verify elastomer compliance with the relevant food-contact regulation in your market. In hot oil and asphalt service, always pre-heat the casing to the medium temperature before start-up so internal clearances are at operating dimension - a cold start against solidified product is the single most common cause of gear pump failures reported from the field.

Commissioning & Maintenance Guidance

Before first start: verify rotation direction, fill the casing with medium, open the discharge bypass, and jog the motor to confirm free rotation. Check the relief valve setting against the system design pressure and lock the adjuster. During the first hour, record suction and discharge pressures, medium temperature, and motor current - deviations from the quotation duty point usually indicate suction restriction or an over-throttled discharge line. Routine maintenance intervals: inspect the shaft seal weekly during the first month, then monthly; check coupling alignment after any pipe work; drain and inspect the bearing housing annually. Keep a log of running hours so rotors, bearings and seals can be replaced on condition rather than after failure.

Troubleshooting Quick Reference

No delivery or loss of prime: check suction line for air ingress, verify foot valve and strainer are submerged and clean, and confirm the casing is primed for pumps without self-priming capability. Flow below nameplate: verify actual rotational speed against the data sheet, confirm medium viscosity is within the rated band, and inspect internal clearances for wear if the pump has long service hours. Abnormal noise or vibration: usually coupling misalignment, cavitation from excessive suction lift, or foreign matter in the pumping chamber. Seal leakage: confirm flush plan and seal face condition; never run a mechanical seal dry. Motor overload: check for over-viscous medium at start-up temperature and confirm the relief valve is not set above the motor's capability. For anything beyond these basics, send us the serial number and symptom - our engineers will respond with a diagnosis.

📋 Standards, Testing & Documentation

Gear pumps in this catalog are designed and acceptance-tested with reference to JB/T 6434 (external gear pumps), three-screw pumps to GB/T 10886, centrifugal chemical pumps to ISO 2858, and sealless or screw pumps to the relevant API 676 guidance, with mechanical seals supplied to API 682 configurations on request. Sanitary models are manufactured with surface finishes suitable for FDA / 3A style hygienic duties. Each shipment can include: performance test record against the quoted duty point, hydrostatic test certificate, material certificates for pressure-retaining parts, operating and maintenance manual, and a dimensional drawing with flange table. Tell us which standards your project specification cites and we will align the documentation pack accordingly.

🔧 Spare Parts & After-Sales Support

Every pump model page doubles as a spare-parts reference: rotor and gear sets, bearing and thrust assemblies, complete seal cartridges, relief valve kits and jacket gasket sets are manufactured in-house to the same drawings as the original build - so spares ordered years later still match. Recommended commissioning spares are one seal set and one gasket set per pump; for critical continuous-duty installations we recommend a full rotor set held on site. When ordering spares, quote the pump serial number and nameplate data so the correct material and clearance class is supplied. Technical support in English is available by email during China business hours, with video call diagnostics available for installation and commissioning issues.

ℹ️ Technical data on this page is sourced from the manufacturer's engineering database and applicable standards (JB/T 6434, GB/T 10886, ISO 2858, API 676). Final selection must be confirmed by our engineers against your actual duty conditions.

⚡ Fastest Response (Under 15 Mins)