420000 Shield 125A Hand for Hypertherm Powermax125 Plasma Cutting Torch Consumables

Product Overview

• Hypertherm Part Number: 420000

• Description: Shield, 125A - Hand

• Compatible Torch: Powermax125 Hand Torch (Torch Body Part# 028478)

• Compatible Systems: All Powermax125 plasma cutting systems (e.g., Powermax1250, Powermax125 Air).

• Amperage Rating: 125 Amps

• Type: Hand Cutting Consumable

Primary Function & Purpose

The Shield is a critical outer consumable part of the plasma torch. Its main functions are:

• Gas Flow Direction: It directs the secondary shielding gas flow around the plasma arc, which helps constrict the arc and improve cut quality.

• Arc Starting: It works in conjunction with the 420200 Retaining Cap to create a properly spaced circuit for the pilot arc to initiate reliably.

• Physical Protection: It protects the more expensive Swirl Ring (420100) and Nozzle (420300/420301) from physical damage caused by contact with the workpiece (drag cutting) or from spatter.

• Standoff Maintenance: The recessed design helps maintain the correct torch-to-workpiece distance (standoff) during hand-cutting operations, especially when using a drag shield.

Key Features & Design

• Drag Shield Feature: The front end is designed to be dragged directly on the metal plate. This allows the operator to maintain a consistent cutting distance without a steady hand, significantly improving ease of use and cut quality in hand-cutting applications.

• Durable Construction: Made from a high-strength, copper-alloy material with a special ceramic coating or insert to resist electrical conductivity and withstand the extreme heat of the plasma arc.

• Cooled by Shielding Gas: The shield itself is cooled by the flow of the secondary gas, preventing it from overheating.

Associated Consumable Set (Commonly Replaced Together)

The 420000 Shield is part of a set of consumables that wear together. A standard hand-cutting consumable set for the Powermax125 includes:

1. Electrode: Part# 420900 (with Hafnium emitter)

2. Nozzle: Part# 420300 (40A FineCut) or #420301 (125A Regular)

3. Swirl Ring: Part# 420100

4. Shield: Part# 420000 (This part)

5. Retaining Cap: Part# 420200

Symptoms of a Worn or Failing Shield

• Difficulty Starting the Arc: Frequent pilot arc failures or inability to transfer the arc to the workpiece.

• Poor Cut Quality: Excessive dross (uncut metal), beveled edges, or a wide kerf.

• Unstable Arc: The arc may flicker or cut out unexpectedly.

• Visible Damage: A melted, cracked, or heavily eroded front face or internal bore. The ceramic surface will show significant wear.

Maintenance & Usage Tips

• Inspect Regularly: Always inspect the shield's front face and internal bore for damage or excessive wear before use.

• Clean Contact Surfaces: Keep the mating surfaces between the shield and the nozzle clean of metal spatter to ensure good electrical contact and gas flow.

• Replace as a Set: For optimal performance and longest consumable life, it is highly recommended to replace the electrode, nozzle, swirl ring, and shield as a complete set.

• Ensure Correct Consumables: Do not confuse the Hand Shield (420000) with the Machine Shield (420400). Using the wrong shield will prevent the torch from starting correctly.

Ref.  FM.420000 Shield for Plasma Cutting Consumables

We have own factory and can supply plasma cutting parts (Shield, Retaining cap, Nozzle, Swirl ring, Electrode)