Main accessories of API610 chemical pump
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The main accessories of API 610 chemical pumps are not a single list, but a highly modular and standard interchangeable "engineering building block" system. According to the first-hand product information of brands such as Kaiquan, Sulshou, KSB, etc. in the search results, their core accessories can be summarized into four functional modules, and each module has strict API standard constraints in material selection, size, and interface.

Based on verifiable official manufacturer information, we will systematically outline the core accessory system of API 610 pumps for you

1、 Overflow components (defining the hydraulic performance and corrosion resistance of the pump)
This is the core component group that directly contacts the conveying medium and determines the performance and lifespan of the pump.

Accessory Name Function Positioning API 610 Standard/Design Requirements Key Features (from vendor data) Source
Pump body (volute) pressure boundary+energy conversion radial/axial subdivision (according to the profile spectrum); Export>DN80 forced double volute shell structure balances radial force to ensure rotor stiffness; Optional insulation/cooling jacket [1] [3] [8]
Pump cover sealing chamber carrier+pressure bearing rigid design, high pressure bearing capacity; The pressure shell is composed of a cooling/insulation chamber and a pump body; Configurable API 682 sealing chamber [1] [3] [6] [8]
Impeller hydraulic core closed, single suction radial impeller; Equipped with front and rear wear-resistant rings and balance hole key drive; Optional inducer to improve cavitation; Materials covering S-6/S-8/D-1/D-2, etc. [1] [3] [5] [8] [10]
Wear resistant rings (mouth rings) are replaceable sacrificial parts, and the pump body/pump cover/impeller are all equipped with replaceable mouth rings; Gap and Hardness API 610 Mandatory Protection for Pump Body/Impeller Body, Low Cost Recovery Efficiency [1] [3] [5]
Shaft sleeve protection+sealing mating surface. The shaft sleeve forms a replaceable wear surface in the packing/sealing area with a fully sealed shaft design. The shaft does not come into contact with the medium and is sealed with an O-ring
The throat liner sealing chamber inlet throttling API 610/682 is defined as a fixed type (pump factory) or floating type (seal factory) located between the impeller and the seal; Improve flushing efficiency [2]
Key points of the project:

The impeller, wear-resistant ring, pump body/pump cover mouth ring form an axial force balance system (balance hole+front and rear mouth rings), and the residual axial force is borne by the thrust bearing.

Throat liners are not standard and are only configured under specific API flushing schemes (Plan 23/32) to increase sealing chamber pressure or isolate media.

2、 Rotor support and transmission components (determining mechanical reliability)
This is the mechanical foundation that ensures the long-term continuous operation of the pump and resists vibration and wear.

Accessory Name Function Positioning API 610 Standard/Design Requirements Key Features (from vendor data) Source
Pump shaft torque transmission+rotor core heavy-duty shaft; The bearing spacing meets the API 610 critical speed requirement, where the first critical speed is greater than the operating speed; Axial radial runout ≤ 0.05mm [4] [5] [9]
Bearing component rotor support+axial force bearing life ≥ 25000 hours (optional mandatory); Thin oil bath lubrication oil slinger+constant position oil cup; Optional oil mist/grease lubrication; Air cooling/water cooling [1] [3] [4] [8] [9]
Installation and heat dissipation of bearings in the bearing housing made of cast iron/steel; Equipped with cooling jacket/heat dissipation fin labyrinth dustproof disc/bearing isolator/magnetic oil seal [1] [3] [5] [8]
Coupling motor pump torque connection extended diaphragm coupling (API 610 standard) can be disassembled without moving the motor; High load-bearing capacity, maintenance free [9]
The anti loosening nut with steel wire thread sleeve for axial fixing of the impeller nut is reliably locked and prevents reverse loosening [1] [3]
Key points of the project:

The thrust bearing configuration is the watershed between API 610 pumps and conventional chemical pumps. OH2 type adopts paired installation of angular contact ball bearings/tapered roller bearings; The VS4/VS6 type adopts oil lubricated thrust bearings (Michel/Kingsbury tilting tile).

The lubrication and cooling method of bearings must be selected according to the medium temperature: natural heat dissipation at T ≤ 200 ℃, forced air cooling/water cooling at T>200 ℃.

3、 Shaft seal and auxiliary system (zero leakage control)
This is the difference between API 610 pumps and API 685 pumps, and it is also the component group with the highest failure rate.

Accessory Name Function Positioning API 610 Standard/Design Requirements Key Features (from vendor data) Source
The size of the sealing chamber of the dynamic shaft seal of the mechanical seal fully complies with API 682; Configurable single/double/series/metal corrugated tube container structure (mandatory); Flushing Plan 11/21/23/32/53/54, etc. [1] [3] [6] [8] [9]
Sealing gland installation and secondary contact with throttling liner (atmospheric side) graphite/bronze throttling liner, leakage control basic component [2]
Sealing flushing system sealing environment control API 682 pipeline scheme; Cooling/filtering/pressurization external flushing (Plan 32) requires the use of a floating throat liner [2] [6]
Quick cooling/blowing system to prevent coking/crystallization API 62 scheme, combined with steam/nitrogen blowing of throttling liner, to keep the sealing surface clean [2]
Key points of the project:

The throttling liner and throat liner are two easily confused accessories: the throat liner is located upstream of the seal (on the medium side), and the throttling liner is located downstream of the seal (on the atmospheric side). The former is a pump component, while the latter is a sealing component.

The API 610 pump itself does not produce seals, but the sealing chamber size, gland interface, and pipeline interface must be reserved according to the API 682 standard to ensure that products from different sealing manufacturers can be directly installed.

4、 Pump body structure and installation accessories
Accessory Name Function Positioning API 610 Standard/Design Requirements Key Features (from vendor data) Source
Pump body support (centerline) maintains centerline support structure (centerline support) at high temperatures to prevent deformation and misalignment of the pump body caused by high-temperature thermal expansion [1] [3] [6] [9]
Import and export flange pipeline connection ASME B16.5 150 #/300 # (standard); The flange load capacity meets the requirements of API 610 for horizontal suction inlet and vertical discharge outlet; Consistent pressure levels [5]
Auxiliary interface instrument/flushing/drainage G-thread/NPT thread standard interface pressure gauge, thermometer, flushing pipe, drainage valve interface [5]
Install base plate foundation fixed steel/epoxy coating; VS4/VS6 pumps with anchor bolt holes require dedicated installation plates/blind flanges [4]
Key points of the project:

Centerline support is a mandatory structural feature of API 610 OH2 pumps, distinct from the foot support of ISO 2858 pumps. Under high temperature conditions, the centerline support ensures that the thermal expansion of the pump body extends uniformly to all sides, and the coupling alignment is not damaged.

The flange pressure rating is usually higher than the design pressure of the pump body, ensuring the sealing reliability under pipeline load.

5、 Quick search for differences in main accessories of various pump types in API 610
Accessory category OH2 (horizontal cantilever) BB3/BB4/BB5 (two end support) VS4/VS6 (vertical suspension)
Pump body form: radial subdivision, volute shell, axial subdivision (BB3)/segmental type (BB4)/cylinder bag (BB5), guide shell+column pipe+discharge elbow
Impeller arrangement single-stage cantilever multi-stage series/back-to-back multi-stage centrifugal/mixed flow, immersion type
Bearing system: rolling bearings+oil lubricated rolling/sliding bearings+forced oil lubricated thrust bearings (top)+guide bearings (medium lubrication)
Number of shaft seals: 1 set (drive end), 2 sets (both ends), and 1 set (top)
Unique accessories include impeller nuts, dust disc balance discs/balance drums (BB4/BB5), intermediate shaft bearings with inter stage bushings, discharge elbows, and blind flanges for installation
Source [1] [3] [5] [8] [9] [7] [4] [10]
6、 Core Conclusion and Information Gap Statement
✅  The conclusion that can be 100% verified in this search is:
The main accessories of API 610 pump are a modular system that is decoupled by function, including overcurrent components (pump body/impeller/wear-resistant ring), rotor components (shaft/bearing/coupling), sealing system (chamber/flushing), and structural accessories (support/flange).

Wear resistant rings (mouth rings) and shaft sleeves are the only sacrificial accessories explicitly listed by all manufacturers as "replaceable, low-cost performance recovery", which is the core design philosophy of API 610 to reduce full lifecycle costs.

Bearings and mechanical seals are the components with the highest failure rate and the most critical selection. API 610 has a lifespan requirement for the former, while API 682 requires interface standardization for the latter.

Throat liner and throttling liner are two completely different accessories, which fall under the responsibility of pump manufacturers and seal manufacturers respectively. Their functional positioning, installation position, and material selection logic are all different.

❌  Information that cannot be provided in this search:
No accessory drawings/dimension tables: No source provides specific values for the wear ring fit clearance, bearing model comparison table, or detailed dimension chain for the sealing chamber. These are the core design parameters of the manufacturer and are not publicly disclosed.

No comparison table between material grades and API standard codes: only listing material categories (such as S-6, D-1), without corresponding relationships between UNS numbers, chemical compositions, mechanical properties, and API standard clauses.

Calculation/selection criteria for bearingless life: only mentioning "life ≥ 25000 hours", without specific algorithms for load factor, equivalent dynamic load, and reliability correction.

No specifications and selection criteria for couplings: only mentioning "diaphragm couplings", without torque rating, allowable misalignment, or API 671 compliance instructions.

There is no complete list of accessories for all BB/VS pumps: KSB only compares the structural differences between BB3/BB4 and does not provide a detailed list of accessories; Finder only summarizes the features of VS1/VS6 without disassembling any accessories.

If you are in the process of purchasing spare parts, preparing maintenance kits, or conducting technical bidding for API 610 pumps, please specify your specific requirements:

Pump type and specifications (such as OH2-150, VS4-8 inches) - I can assist in sorting out the critical vulnerable parts list (CCL) for this type of pump;

Specific accessories of concern (such as wear-resistant rings, bearings, throat liners) - I can provide material selection and tolerance principles based on API standards;

Manufacturers to be compared (Flowserve/Sulzer/KSB/Kaiquan) - I can organize known information on the universality/interchangeability of accessories from various brands.

The current search results have revealed the framework knowledge system of API 610 pump accessories, but detailed engineering level data must be obtained through formal technical channels (manufacturer's product manual, API standard original text, professional design manual).