4040 and 8040 RO membrane connectors, also called permeate interconnectors or couplers, join the product-water tubes of adjacent spiral-wound membrane elements inside a pressure vessel. Their role is to maintain alignment and provide the correctly dimensioned sealing interface for the connector O-rings.
WECOME supplies yellow moulded ABS connectors for standard 4040 and 8040 element programmes. The connector body, groove geometry, insertion depth and O-ring specification must match the membrane permeate-tube bore and the pressure-vessel element train. A connector alone does not create a seal; the approved O-rings and correct assembly are essential.
Where the Connector Sits Inside a Multi-Element Vessel
The yellow connector is inserted into adjacent permeate-tube bores. Product water passes through the connected central-tube path; feedwater travels through the element feed channels outside that path.
Available 4040 and 8040 Connector Models
4040 RO membrane connector
Yellow ABS interconnector for compatible 4-inch industrial, commercial and large residential RO element trains.
8040 RO membrane connector
Yellow ABS interconnector for compatible 8-inch industrial RO membrane element trains and pressure-vessel assemblies.
4040 / 8040 RO Connector Specifications
| Part Number | Product Name | Material | Appearance | Qty / Box | Boxes / Pallet | Carton Dimensions | G.W. / Box |
|---|---|---|---|---|---|---|---|
| CONNECT-4040 | 4040 RO Connector | ABS | Yellow ABS | 500 pcs | 40 | 460 × 460 × 300 mm | 15 kg |
| CONNECT-8040 | 8040 RO Connector | ABS | Yellow ABS | 500 pcs | 20 | 460 × 460 × 300 mm | 25 kg |
The supplied schedule does not include connector OD, bore, insertion length, shoulder dimensions, groove dimensions or O-ring specification. A model name such as 4040 or 8040 is not sufficient for interchangeability; approve a dimensioned drawing or physical sample before bulk ordering.
How the Permeate Interconnector Works
Centre adjacent permeate tubes
The connector guides the product-water bores of neighbouring elements into a common axial path.
Compress the O-rings
Correct groove and bore geometry produce the specified O-ring squeeze without cutting, rolling or excessive friction.
Carry permeate between elements
Collected product water flows through the interconnected central tubes toward the vessel permeate outlet.
Maintain the assembled train
Correct length, shimming and end-adapter design limit movement that could load or damage the connection.
Key Product Priorities
Precision moulded geometry
Connector OD, bore, shoulders and seal grooves must remain within the drawing tolerance for reliable assembly.
Stable ABS construction
The moulded body supports alignment and handling when the material grade is approved for the intended water and temperature.
Controlled O-ring interface
Correct groove finish and dimensions help the specified O-rings seal without extrusion, cutting or excessive compression.
Clean internal flow path
A smooth bore and flash-free moulding reduce obstruction and contamination risk in the permeate collection path.
4040 and 8040 options
Separate models support compatible 4-inch and 8-inch membrane-element production and replacement programmes.
Bulk factory packaging
Five hundred pieces per carton support repeat assembly, incoming inspection and production-line replenishment.
How to Specify an RO Membrane Connector
Identify the element format
State 4021, 4040, 8040 or another format, but also provide the permeate-tube drawing and element manufacturer.
Define every critical dimension
Include bore, connector OD, overall length, insertion depth, shoulder and O-ring groove dimensions with tolerances.
Specify the O-ring system
Provide material, hardness, cross-section, quantity, lubricant and required squeeze. Confirm whether O-rings are included.
Review operating conditions
Share permeate pressure, water temperature, chemistry, sanitisation and cleaning agents.
Approve assembly fit
Check insertion force, alignment, removal, O-ring damage and movement using real permeate tubes and adapters.
Validate the element train
Complete the manufacturer’s leak, pressure and permeate-quality checks after the vessel is assembled and shimmed.
Application Fit Across Industrial and Residential Systems
Match the connector to the membrane format, not only the industry
The same application may use different element sizes. Confirm that the installed RO train actually uses compatible 4040 or 8040 permeate tubes.
Large residential: typically 4040 only
Incoming Inspection and Assembly Control
Most connector failures start at the interface
Inspect the connector, O-rings, mating bores and assembly process together. A visually clean ABS part can still leak if dimensions, seal squeeze or alignment are wrong.
Frequently Asked Questions
What does a 4040 or 8040 RO membrane connector do?
It joins the permeate collection tubes of adjacent membrane elements inside a pressure vessel so product water can pass through a continuous central-tube path.
Does the ABS connector itself prevent leakage?
No. The connector provides the body and seal-groove geometry, while correctly specified O-rings form the pressure seal against the permeate-tube bores.
Are 4040 and 8040 connectors interchangeable?
No. They serve different element formats and may have different diameters, lengths, grooves and O-rings. Approve the exact drawing or sample.
Can this connector be used in household RO systems?
CONNECT-4040 may be relevant to whole-house or large residential systems that actually use 4040 elements. It is not intended for standard 1812 or 2012 point-of-use membrane cartridges unless a separate compatible design is supplied.
Can WECOME supply a 4021 connector?
A 4021 or custom connector can be evaluated from the permeate-tube drawing, O-ring requirements, sample, order quantity and operating conditions. It is not included in the two-model specification table.
Are O-rings included with the connector?
The supplied data does not confirm this. State the required O-ring material, hardness, cross-section and quantity in the enquiry and quotation.
What information should be included in a connector enquiry?
Provide the element size and manufacturer, permeate-tube drawing, connector dimensions, O-ring specification, water chemistry, pressure, temperature, certification requirements and annual quantity.
Related Products and Technical Resources
Confirm the Connector from Your Permeate-Tube Drawing
Send the element format, bore dimensions, O-ring specification, pressure-vessel arrangement and operating conditions.