WhatsApp: +86 13062750528sales@tungarc.com
TungArcTungArcPrecision in Every Contact
Menu
Home
Products
Bronze Series
Copper Tungsten (CuW)
Tulip Contact
Silver Tungsten (AgW)
Search products
Popular

Resources

Technical Resources

Articles, guides, and industry news.

Technical Resources9 min read

Sourcing Copper Tungsten Contacts from China: What to Verify Before the First Order

China produces a large share of the world's infiltrated copper tungsten, and for switchgear OEMs and service companies outside China it is usually the price-competitive source. It is also a market where a well-designed website, an ISO certificate and a confident quote tell you very little about whether the parts will pass incoming inspection. This article is a verification list: what to ask for, what to check, and what a good answer looks like, before the first purchase order.

Read Article →
Technical Resources9 min read

How to Specify Copper Tungsten Contacts on a Drawing: Density, Hardness, Conductivity and Infiltration Notes

Most disputes between a switchgear OEM and a contact supplier trace back to a drawing that says "Material: CuW80" and nothing else. The supplier delivers a part that is 80 percent tungsten. The OEM's incoming inspection rejects it for low density, or the wrong hardness unit, or a braze joint with no acceptance limit to check against. Both sides are right, and the drawing is wrong.

Read Article →
Technical Resources8 min read

GB/T 8320 vs ASTM B702 vs RWMA Class 10/11/12: Copper Tungsten Grade Cross-Reference

A drawing from a European OEM says "WCu 80/20". A drawing from a North American switchgear builder says "RWMA Class 12". A Chinese supplier's material certificate says "CuW80 per GB/T 8320". Are these the same material? Nearly, but not exactly, and the differences matter when the material certificate has to satisfy the drawing. This article lays out the three main designation systems side by side and explains where they line up and where they do not.

Read Article →
Technical Resources8 min read

Why Type Testing Is Done at Apparatus Level, Not on the Contact Itself

A procurement engineer evaluating a new contact supplier will sooner or later ask: "Are your contacts type tested to 145 kV?" or "Can you supply contacts rated for 420 kV?" The question is reasonable. The answer, from any honest component supplier, is that contacts are not type tested and do not carry a voltage rating. The circuit breaker or GIS bay is. This article explains why that is, what a contact supplier actually is responsible for, and what evidence a buyer should ask for instead.

Read Article →
Technical Resources8 min read

Silver Tungsten for LV Apparatus: A Selection Guide

Silver tungsten (AgW) is the standard contact material for low-voltage electrical apparatus — AC contactors, motor starters, relays, and LV circuit breakers. Sourcing AgW involves two decisions beyond the grade: which physical form (tip, rivet, custom) and which grade for your duty. This guide covers both, with product recommendations.

Read Article →
Technical Resources8 min read

Conductor Material Selection for MV Switchgear

The current path through MV switchgear — from cable termination through the breaker contacts to the outgoing bus — runs through conductors that have to balance three things: conductivity, mechanical strength, and arc tolerance at exposed segments. No single material wins on all three, so most switchgear current paths combine materials. This guide explains how to choose conductor material and which product to source for each segment.

Read Article →
Technical Resources8 min read

Bronze Components in MV Switchgear: When to Use What

Bronze fills the spaces in MV switchgear where copper is too soft and copper tungsten is overkill — bushings, contact fingers, commutator plates, rings, and the precision machined parts that make breaker and disconnector mechanisms work. The catch is that "bronze" covers several alloy families with different properties. This guide explains which bronze alloy fits which job, and which product to source.

Read Article →
Technical Resources8 min read

Tulip Contact Selection for MV Switchgear

Tulip contacts are the plug-in connection in withdrawable MV switchgear — the multi-finger spring-loaded contacts that let you rack a breaker in and out without de-energizing the bus. Choosing the right tulip contact comes down to three things: current rating, whether you need arc resistance, and whether your application is standard switchgear or something else (like a surge arrester). This guide walks through the options.

Read Article →
Technical Resources9 min read

Copper Tungsten Components for MV Switchgear: A Sourcing Guide

If you're building or refurbishing medium-voltage switchgear, copper tungsten (CuW) shows up in more places than just the obvious arc contacts. Shielding caps, conductive rods, contact plates, guide pins — the CuW family covers a dozen distinct component types, each for a specific job inside a vacuum interrupter or switchgear assembly. This guide walks through which CuW component fits which application, so you can match the right part to your design or sourcing requirement.

Read Article →