Product
Product Details
Brass Hollow Pins / Tube Pins
Brass Hollow Pins and Tube Pins – Wire Feed-Through and Fluid Connector Pins
Brass hollow pins and brass tube pins are precision-machined cylindrical components with a longitudinal through-bore, used in applications requiring wire feed-through, fluid passage, gas venting, weight reduction, or insertion of inner contact elements. They are used in feed-through connectors, lamp holder contacts, lighting fixture pins, coaxial contacts, fluid connector pins, pivot tube pins, and bearing pin applications. Electrical Accessories India manufactures brass hollow pins with bore diameters from 0.5 mm to 20 mm and outer diameters from 1.5 mm to 50 mm, with wall thicknesses from 0.3 mm upward. Price: US$ 11.50/kg
Product Overview
Wire Feed-Through Tube Pins
Brass hollow tube pins used as wire feed-through contacts are commonly found in lamp holders (Edison screw E14, E27, E40 bases), bayonet cap (B22) lamp holders, and architectural lighting fixtures where the conductor wire passes through the pin bore to the center contact terminal. The pin’s hollow bore eliminates the need for external wiring around the contact and simplifies assembly of sealed and weather-resistant lamp holders. Feed-through bore diameters of 1.0 mm, 1.5 mm, and 2.0 mm accommodate standard single and multi-strand copper conductors used in lighting applications.
Coaxial Contact Tube Pins
In coaxial and RF connector applications, hollow tube pins (also called coaxial center contacts) carry the signal conductor through the center of a coaxial connector while allowing inner conductor insertion and termination. These hollow contact pins are precision-bored to very tight tolerances (±0.02 mm bore diameter) to ensure consistent characteristic impedance of 50 Ω or 75 Ω in SMA, TNC, BNC, and N-type connector assemblies. Pin geometry is dimensioned per MIL-DTL-39012, IEC 61169-1, and IEC 61169-4 coaxial connector standards.
Fluid Connector Tube Pins
Brass hollow tube pins in fluid connector applications allow hydraulic fluid, compressed air, cooling water, or gas to pass through the connector while maintaining electrical contact on the outer pin surface. These are used in combined electrical/fluid connectors for pneumatic cylinders, hydraulic actuators, and cooling system manifolds in industrial equipment. Bore dimensions and sealing groove positions are designed per fluid connector housing specifications.
Pivot and Hinge Tube Pins
Hollow tube pins used as pivot pins and hinge pins provide the pivot axis for rotating and oscillating mechanisms in switchgear, relay arms, and mechanical linkages. The hollow bore reduces pin weight and moment of inertia in high-speed mechanisms, while allowing lubricant feed-through via the bore to internal bearing surfaces. Outer surface hardness of brass pivot tube pins is in the range of 80–100 HB, providing adequate wear resistance for typical oscillating pivot applications.
Lamp Holder Contact Pins
Brass hollow tube pins in lamp holder applications (E14, E27, E40 Edison screw base) serve as the center pin contact for the lamp base. The hollow bore accommodates the lamp’s center contact wire and provides the live conductor path in the lamp holder circuit. Nickel plating (3–5 µm) protects against tarnishing in lamp holder environments. Compliance with IEC 60238 (Edison screw lamp holders) and IEC 61184 (bayonet lamp holders) governs dimensional and material requirements for lamp contact pins.
Related Products for Complete Connector Systems
Brass hollow tube pins are used alongside Brass Solid Pins for solid contact elements, Brass Plug Pins for industrial connector applications, Brass Sockets For Pins as mating female contacts, Brass Terminal Pins for wire termination, and Brass IEC Appliance Inlet Pins for standardized appliance connections.
Key Features
- Through-bore from 0.5 mm to 20 mm inner diameter
- Outer diameter from 1.5 mm to 50 mm
- Wall thickness from 0.3 mm (thin-wall) to heavy-wall tube pins
- Precision bored to ±0.02 mm bore tolerance
- Nickel, tin, silver, and chrome plating options
- Lamp holder contact pin compliant with IEC 60238
- Coaxial contact pin compliant with IEC 61169 series
- RoHS and REACH compliant
Thin-Wall Hollow Pins
Thin-wall brass hollow pins (wall thickness 0.3–0.8 mm) are used in lightweight electrical contacts, ferrule connectors, and crimp-type electrical terminations where a hollow pin structure reduces material weight while maintaining current-carrying cross-section. These are produced by deep-bore drilling on CNC lathes or by tube-drawing processes.
Stepped Bore Tube Pins
Stepped bore brass tube pins have two or more bore diameters along their length, providing a shoulder for wire stop, inner contact alignment, or spring stop in assembled connector systems. Stepped bore tolerances maintained to ±0.02 mm on each bore step.
Brass Ferrule Contact Pins
Hollow brass ferrule pins used in push-in terminal blocks and spring-cage terminals accept stripped wire ends or wire ferrules (Aderendhülsen) for secure, vibration-resistant wire termination in DIN rail terminal blocks. Compatible with standard wire ferrule sizes per DIN 46228 and IEC 60228.
Cross-Drilled and Ported Tube Pins
Cross-drilled hollow pins have radial holes through the wall for fluid distribution, air venting, lubricant injection, or electrical cross-connection. Radial hole diameters and positions are machined per customer specification on CNC multi-axis turning/milling centers.
Sealed-End Tube Pins
Sealed-end tube pins (blind bore) have one open end for wire insertion and one sealed end for mechanical retention. Used in solder cup connectors where wire is inserted into the bore and soldered, and in sealed connector contacts for hermetic sealing with glass-to-metal or epoxy sealing compounds.
Technical Specifications
| Parameter | Specification |
|---|---|
| Outer Diameter | 1.5 mm – 50 mm |
| Inner Bore Diameter | 0.5 mm – 20 mm |
| Wall Thickness | 0.3 mm – 15 mm (varies with OD) |
| Length | 3 mm – 200 mm |
| Bore Tolerance | ±0.02 mm (standard); ±0.005 mm (precision) |
| OD Tolerance | ±0.01 mm (standard) |
| Material | Brass CW614N / CW602N / C46400 |
| Plating | Nickel / Tin / Silver / Chrome / Gold |
| Surface Roughness (OD) | Ra ≤ 1.6 µm (turned) |
| Operating Temp. | -40°C to +200°C |
| Price | US$ 11.50/kg |
Material Grades
| Material | EN | ASTM | BS | Application |
|---|---|---|---|---|
| Free-Cutting Brass | CW614N | C36000 | CZ121 | General hollow pins |
| DZR Brass | CW602N | C35300 | CZ132 | Marine fluid connectors |
| Naval Brass | CW712R | C46400 | CZ112 | High-pressure fluid pins |
Product Types
| Type | Description | Application |
|---|---|---|
| Lamp Holder Contact Pin | Hollow brass, nickel plated, IEC 60238 | E14, E27, E40 lamp holders |
| Coaxial Center Contact | Precision bore ±0.02 mm, 50/75 Ω | SMA, TNC, BNC connectors |
| Wire Feed-Through Pin | Smooth bore for conductor passage | Sealed connectors, weatherproof |
| Fluid Connector Tube Pin | Pressure-rated bore, sealing grooves | Pneumatic/hydraulic connectors |
| Ferrule Contact Pin | Small diameter, smooth bore | Spring-cage terminals, DIN rail |
| Cross-Drilled Tube Pin | Radial holes in body | Lubrication, fluid distribution |
Applications by Industry
| Industry | Application |
|---|---|
| Lighting Manufacturing | E14/E27/E40/B22 lamp holder center pins |
| RF/Microwave Connectors | Coaxial center contact tube pins |
| Industrial Automation | Fluid connector pins, pneumatic systems |
| Electrical Panel Mfg. | Feed-through ground studs, pivot pins |
| Terminal Block Mfg. | Ferrule contact pins for spring-cage terminals |
| Marine / Offshore | DZR hollow pins for salt-fog environments |
| Defense / Aerospace | Hermetic sealed hollow contact pins |
Manufacturing Process
Brass hollow tube pins are produced by CNC turning with deep-bore drilling on Swiss-type lathes and gun-drilling for deep precision bores. The outer profile is turned first, then deep-bore drilling produces the through-hole in a single operation with specialized indexable boring tools and gun drills. For thin-wall hollow pins with wall thickness below 1 mm, seamless brass tube stock (EN 12449 / ASTM B135) is used as starting material, and the outer profile is turned from tube. Bore surface finish is improved by reaming or honing where required. Stepped bores are produced in sequential boring operations with individual tool setups. All bore dimensions are verified using bore gauges, plug gauges, and coordinate measuring machines.
Quality Standards
| Standard | Scope |
|---|---|
| ISO 9001:2015 | Quality Management System |
| IEC 60238 | Edison screw lamp holder pins standard |
| IEC 61169 | RF coaxial connectors — performance standard |
| MIL-DTL-39012 | Coaxial connector contacts specification |
| EN 12449 | Seamless brass tube for machining |
| RoHS 2011/65/EU | Hazardous substances restriction |
Why Choose Electrical Accessories India
- Deep-bore drilling and gun drilling capability for precise through-bores
- Thin-wall hollow pins from brass tube stock per EN 12449
- Lamp holder pins compliant with IEC 60238
- Coaxial contact pins to MIL-DTL-39012 dimensions
- ISO 9001:2015 certified with CMM bore inspection
- Competitive pricing at US$ 11.50/kg
FAQ – Brass Hollow Pins / Tube Pins
Q1. What is the minimum wall thickness for brass hollow pins?
Minimum wall thickness is 0.3 mm for small-diameter hollow pins made from brass tube stock. CNC-drilled hollow pins have minimum wall thickness of 0.5 mm to maintain structural integrity.
Q2. Do you supply lamp holder contact pins for E27 base?
Yes. We supply E27, E14, and E40 Edison screw lamp holder center contact pins compliant with IEC 60238 dimensional requirements.
Q3. Can hollow pins be used as coaxial connector center contacts?
Yes. Precision-bore hollow brass tube pins are manufactured as center contacts for SMA, TNC, BNC, and N-type coaxial connectors per IEC 61169 and MIL-DTL-39012.
Q4. What bore diameter tolerance do you achieve?
Standard bore tolerance is ±0.02 mm; precision-bored and reamed bore tolerance is ±0.005 mm for coaxial contact and precision tooling applications.
Q5. Do you supply DZR brass hollow pins for marine applications?
Yes. DZR brass (CW602N) hollow pins are available for marine and coastal electrical installations requiring dezincification resistance.
Q6. What is the maximum bore-to-OD ratio?
Maximum bore-to-OD ratio is approximately 0.85 (85% of OD) for thin-wall hollow pins made from tube stock. Practical minimum wall thickness for structural integrity is 0.3 mm.
Q7. Can you supply cross-drilled hollow pins?
Yes. Radial cross-holes are machined on CNC multi-axis centers. Hole diameters from 0.5 mm and positions per customer drawing.
Q8. What plating do you recommend for lamp holder hollow pins?
Nickel plating (3–5 µm) over brass is standard for lamp holder contact pins, providing corrosion resistance and good contact properties per IEC 60238 requirements.
International Terminology
| Language | Term 1 | Term 2 | Term 3 |
|---|---|---|---|
| Spanish | Pines huecos de latón | Pines tubulares de latón | Espigas huecas latón |
| Russian | Латунные полые штифты | Трубчатые штыри из латуни | Полые пины латунь |
| French | Broches creuses en laiton | Broches tubulaires laiton | Goupilles creuses laiton |
| Portuguese | Pinos ocos de latão | Pinos tubulares de latão | Espigas ocas latão |
| Italian | Spine cavi in ottone | Spine tubolari in ottone | Perni cavi ottone |
Related Products
- Brass Plug Pins
- Brass Sockets For Pins
- Brass Earth Ground Pins
- Brass Test Pins / Probe Pins
- Brass Spring Contact Pins (Pogo Pins)
- Brass Header Pins / Male Connector Pins
- Brass Terminal Pins
- Brass Dowel Pins
- Brass Round Pins / Solid Pins
- Brass IEC Appliance Inlet Pins
Request a Quote
📧 Email: sales@elecaccs.com | 📞 Phone: +91-22-43449300
📍 Plot 10, GIDC Industrial Estate, Jamnagar 361004, India