A replacement DTH drill bit has to satisfy two different requirements: it must produce the required hole, and its shank must match the intended hammer. Head diameter answers the first question. It does not, on its own, answer the second.
Start the enquiry with the exact hammer identification and the reference for the bit being replaced. Once the interface has been checked, compare the required diameter, face design and button arrangement for the application. Keeping that order avoids selecting a cutting head before establishing which connection is needed.
Record the hammer identity before comparing bits
Provide the hammer manufacturer, exact model or series, and any identification or serial information available on the unit or its records. Include the existing bit's part number or a previous approved purchase reference. If the equipment has been modified or its identification is incomplete, describe that uncertainty in the enquiry.
A general size description may be useful for an initial search, but it is not an approved interface specification. Keep the exact model reference attached to photographs and drawings so the supplier knows which assembly the proposed bit must match.
Separate head diameter from the shank interface
The bit head, shank and hammer perform connected roles, but they should appear as separate fields in a replacement enquiry. A head diameter can be available in more than one interface configuration. Conversely, identifying a shank family does not finish the choice of head size or face arrangement.
Epiroc's DTH catalogue illustrates this distinction by presenting shank information separately from bit diameter and cutting-head details. Use that distinction as an identification method. Another manufacturer's catalogue is not evidence that a particular FSDRILL bit is approved for a named hammer.
Build a useful identification photo set
If an approved drawing or part reference is available, send it first. Photographs then help relate the physical bit to that reference. If the reference is missing, a consistent set of photographs gives the technical review a stronger starting point:
- A full side view showing the complete bit, including the head and shank.
- A rear or end view showing the shank end and visible interface features.
- A clear head-face view showing the buttons and visible flushing outlets.
- Close-ups of markings, part references and any area relevant to identification.
- A scale or dimension record, with each measurement tied to a defined feature.
Use separate, well-lit views rather than a single angled image. Keep the original image resolution so markings can be read. A photograph of the face alone is usually a weak reference for the rear interface.
Match dimensions to a drawing reference
Where dimensions are needed, agree which features and reference points are being measured. Overall length, shank geometry and retention-related features only become comparable when both parties use the same drawing definitions. A list of numbers without reference points can create apparent agreement between different measurements.
Spline count is one identification clue. It does not establish the complete spline geometry or the rest of the interface. Likewise, similar overall appearance is insufficient to confirm fit. Compare the full specified interface against the intended hammer reference.
Take wear into account when using an old bit. Rounded or damaged features may no longer represent the original design dimensions. Label sample measurements as measurements of the used part, and distinguish them from values taken from an approved drawing. If those sources conflict, resolve the difference before treating the sample as the manufacturing specification.
Confirm the head configuration after the interface
With a matching interface reference established, state the required nominal head diameter and describe the application. Include the formation, relevant drilling conditions and the current replacement reason, such as normal wear or a request to review the cutting layout.
Discuss the face and button arrangement for that job using the selected product's specification. A change to the cutting head should be an explicit selection, rather than an assumption hidden inside the word “replacement.” Where the existing configuration has an approved record, identify whether the request is for the same arrangement or a proposed alternative.
The FSDRILL product's model suffix, including a reference such as P350, should not be treated as independent proof of compatibility. The enquiry and quotation need to identify the hammer and matching interface directly. A suffix may help locate a product record; it does not replace that check.
Put the replacement decision in one record
| Field | What to attach or record |
|---|---|
| Hammer | Manufacturer, exact model or series, identification details and available records |
| Existing bit | Part reference, markings, approved drawing or previous confirmed specification |
| Interface | Matching shank reference and any dimensions checked against defined drawing features |
| Cutting head | Required diameter, face/button arrangement and any requested change |
| Application | Formation and relevant conditions for reviewing the selected configuration |
Before ordering, make sure the proposed replacement and its agreed interface reference are identified in the quotation or approved specification. For a distributor holding repeat stock, keep that record with the product identification so that a later reorder does not rely on a photograph or head diameter alone.
View the FSDRILL DTH drill bit and send the hammer reference with your existing-bit information. If you are choosing the drilling system rather than replacing a bit, begin with the top hammer versus DTH guide.