DRAWING-BASED FILTER INTERFACE GUIDE

Metal Filter Element End Connections & Sealing Guide

A metal filter element end connection must locate the element, transfer mechanical load and control the intended sealing path. Specify the mating component, connection geometry, seal location, tolerances, flow direction and allowable bypass—not only “threaded” or “flanged.”

Stainless steel filter elements with external threaded end connections
Real Maidong cylindrical filter elements with external threaded ends and support cages.

What the End Connection Must Do

Locate the element

Control radial and axial position inside the housing.

Carry assembly load

Transmit tightening, pressure, handling and removal forces.

Create the seal

Define the face, O-ring, gasket, cone or thread-seal interface.

Prevent bypass

Close unintended paths around the media and end attachment.

Metal Filter Element End Connection Comparison

Connection names are only categories. The controlled drawing must show the exact mating geometry, the surface that seals and the dimensions that remain critical after welding or assembly.

Connection typeDrawing detailsSeal questions
Male / female threadStandard, size, pitch, class, length, lead-in and shoulderThread seal, O-ring, gasket or separate face?
Flange or collarOD/ID, thickness, bolt pattern, seating face and flatnessGasket location, compression and bypass path?
Open / slip-fit endControlling diameter, insertion depth, stop, clearance and retentionHousing O-ring, interference fit or no seal?
Closed end capCap form, depth, attachment, pressure side and unsupported areaIs the media-to-cap joint a bypass boundary?
Welded interfaceJoint location, weld scope, distortion limits and post-weld dimensionsWhat leakage or inspection requirement applies?
Threaded filter element end fittings with internal hex drive features
Threaded ends with internal drive features for installation; dimensions must follow the mating design.

Threaded Filter Element Connections

State the thread system and designation completely. Include male or female form, pitch, tolerance/class, engagement length, runout or relief, lead-in, shoulder position and installation feature. A photograph cannot define a thread.

Do not assume the thread is the seal. Show whether sealing occurs on the thread, an O-ring groove, a gasket face, a cone or a separate shoulder.

Flanges, Collars and Open Ends

For a flange or collar, define OD, ID, thickness, bolt pattern if present, locating diameter, seating face and flatness. For an open slip-fit end, define insertion depth, controlling diameter, clearance, stop and retention method.

The housing drawing should show where the element seats and how it is removed without damaging the media or seal.

Perforated metal filter elements with open and closed end caps
Open-rim and formed closed-end configurations shown before equipment installation.

Seal Interface and Bypass Checklist

Seal position

Mark the exact face, groove or thread region that creates the barrier.

Seal specification

State gasket/O-ring standard, material requirement and service conditions.

Compression control

Define groove, shoulder, torque or clamp travel that controls compression.

Adjacent leak paths

Review media-to-cap joints, seams, welds and housing clearances.

A micron rating describes the intended filtration medium, not leakage around the element. Seal integrity and media retention must be specified as separate requirements.

Pleated stainless steel filter cartridges with male threaded ends
Pleated metal cartridges with drawing-specific external threaded connections.

Connection Loads and Finished Tolerances

Threading, end-cap welding and pleat assembly can affect concentricity, length, face position and sealing geometry. Put functional dimensions on the finished element drawing rather than controlling only separate parts.

State normal and reverse flow, differential pressure, installation torque or clamp load, temperature, cleaning method and removal frequency. Do not infer a pressure rating from appearance.

Real Maidong End-Connection Examples

These images show real Maidong metal filter components with several end concepts. They are visual references only; the approved drawing controls every thread, flange, seal and tolerance.

Stainless steel filter elements with external threaded end connections
Real Maidong cylindrical filter elements with external threaded ends and support cages.

Threaded supported elements

Perforated metal filter elements with open and closed end caps
Open-rim and formed closed-end configurations shown before equipment installation.

Open and closed ends

Pleated stainless steel filter cartridges with male threaded ends
Pleated metal cartridges with drawing-specific external threaded connections.

Pleated threaded cartridges

Custom stainless steel filter elements with threaded flanged and closed ends
Representative cylindrical and conical metal filter forms with varied end configurations.

Custom end configurations

Match the Interface to the Filter Structure

Wire mesh cylinder

End hardware must retain the woven medium and close seam or edge bypass paths.

Pleated cartridge

End caps must locate and seal the pleated pack without obscuring the intended flow path.

Sintered element

Porous medium attachment, end machining and seal surfaces are separate drawing controls.

Perforated support body

Open area, welds and end rings must be coordinated with the fine media and housing.

End Connection and Sealing RFQ Checklist

1. Send both mating parts

Show the filter end and housing or receiver geometry.

2. Define the connection

Thread, flange, collar, open end, cap or welded joint.

3. Mark the seal

Identify groove/face, seal type, compression and bypass boundary.

4. Add service data

Flow, pressure, temperature, fluid, cleaning and assembly method.

5. State inspection

Critical dimensions, leakage or inspection records and quantity.

Metal Filter Element Connection FAQ

There is no universal best connection. Select the interface from the housing, assembly method, pressure direction, removal access, cleaning procedure and seal requirement. The mating part and critical dimensions must be defined.

State thread standard, size, pitch, class or tolerance, male or female form, thread length, lead-in, shoulder, tightening feature, seal method, material and mating component.

Not necessarily. Some designs use a thread seal, while others use an O-ring, gasket, cone, shoulder or separate face. Mark the actual sealing surface and leakage path on the drawing.

Bypass can occur through an incorrect seal position, damaged sealing surface, unsuitable compression, dimensional mismatch, an unsealed joint or a leak path around the media-to-end-cap attachment.

Define O-ring standard and material requirement, groove geometry, mating diameter, surface condition, compression direction, assembly movement, temperature, fluid and allowable extrusion gap.

Maidong can review drawing-based threaded, open, capped, collared and flange-style metal filter element enquiries. Feasibility, material, tolerances and inspection scope must be confirmed from the actual drawing.

Request an End-Connection Drawing Review

Send the filter construction, mating component, connection and seal geometry, service conditions, critical tolerances, inspection requirements and quantity.