BLT421S Lower Protective Window, Cartridge and Cover Guide

Buying a replacement for the lower protective-window area of a BOCHU BOCI BLT421S cutting head? First confirm whether you need the optical window, its cartridge, or its cover. These are separate items. This guide helps identify the purchase, not diagnose a cutting fault or carry out a replacement.

Before you choose a replacement

If your installed head is confirmed as BLT421S and the complete replacement record matches D34×5-2S / DP.V.P0049AA, open the D34×5-2S protective-window option on BOCHU.store. Check the selected option before ordering. The listed ≤8 kW condition is an additional cross-check, not a substitute for the model, position or full Part Number.

If you need a cartridge or cover, do not order that window as a substitute. Use the component name and complete code in your machine records to confirm the exact item. A cartridge is not assumed to include a window.

In this guide

Window, cartridge or cover?

The BLT421S manual referenced below names these parts separately. Use the labels to identify the object you are buying.

First lower protective window

The optical protective-window component in the first lower position. The manual diagram calls it D34.0T5-2. That diagram label does not by itself establish the store Part Number, or mean that a second-lower window is the same item.

First lower protective-window cartridge

The carrier assembly identified separately in the manual. Confirm its own complete record and the intended supply contents. Do not assume that buying a cartridge supplies a window, or that buying a window supplies a cartridge.

Lower protective-window cover

A separately labelled cover. The referenced diagram places DP.M.Q0249AA beside this label. This is not the window's order code and is not a confirmed purchase link in this guide.

Second lower protective window or cartridge

A different lower position. The manual lists it separately with a different window size. Do not select it from the first-lower window record.

What to check on your machine records

  1. Confirm the cutting-head nameplate and record the complete BLT421S model, including any suffix.
  2. Identify the position and object: first lower window, second lower window, cartridge, or cover.
  3. Copy the full Part Number from the existing part, packaging or documented replacement record. Keep separators and suffixes.
  4. Compare the complete record with the product's listed model and configuration. Do not derive a Part Number from dimensions, machine power or a shortened diagram label.

The confirmed window option

The store's separate selection record lists D34×5-2S (DP.V.P0049AA), ≤8 kW, for BLT421S. Use this option only when the installed model, lower-window position and complete replacement record agree.

View DP.V.P0049AA on the existing D34 product page. The page contains several D34 configurations, so verify the selected Part Number rather than ordering another option with the same diameter.

For another confirmed lower-window configuration, browse BOCHU BOCI lower protective lenses and match its own product record. This guide does not provide a complete BLT421S bill of materials or establish that another model uses the same part.

Which manual to use

The official BLT421S Product Manual used for the component labels in this guide has “V1.01” in its file name and “V1.0, 2024-03-06” in Document History. Appendix A.1 identifies the components. Appendix A.3 contains the model-specific lower-window replacement procedure.

Confirm the manual version applies to the installed head before following it. A different file date or version label does not establish equivalence. Follow the applicable safety notices, authorization requirements and site procedures. This article does not provide cleaning instructions, replacement intervals or an installation procedure.

When to ask for confirmation

Stop before ordering if the model or code is incomplete, the diagram and package record disagree, or you cannot distinguish the window from its cartridge or cover. A shared diameter, similar appearance or matching power is not enough.

Use the replacement-part confirmation guide to prepare the complete model, component role, Part Number and a clear label or nameplate photo. Once one product record matches, select its exact option on the existing BOCHU.store product page.

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