What the perforations are for
A plain pup joint is solid pipe. A perforated pup joint carries a pattern of holes drilled through its wall, turning that section of the string into a flow point. The applications are practical: an entry point where produced fluid passes from the annulus into the tubing, a circulation point for killing or cleaning out a well, a gas-lift or chemical-injection station, or a drainage and equalising point above a packer. In each case the depth of the ports is the design variable — which is why the perforated pattern rides on a pup joint: the joint's length places the ports, and the ports do the hydraulic work.
One boundary governs everything on this page: perforated pup joints do not appear in this factory's catalogue. The pup joint family lists plain casing and tubing pup joints only, so a perforated sub is an enquiry item, not an order line. Ask in the enquiry whether the pattern can be machined, from what base joint, and on what inspection basis, before the item forms part of any quotation. If it is confirmed, three variables define the part, and all three belong to your completion design: the base joint (size, weight, grade and EUE or NUE ends, exactly as for a tubing pup joint), the hole pattern (hole diameter, number of holes, rows and spacing, and the section of the joint they occupy), and the duty (internal and external pressure, flow direction and whether the joint sits in a corrosive interval). State those three in the enquiry, and ask for the pattern to be confirmed from them in writing before the item forms part of any quotation.
How the hole pattern changes the part
| Pattern variable | Why it matters |
|---|---|
| Hole diameter and count | Set total flow area — the hydraulic size of the entry point |
| Rows and spacing | State the rows and spacing your pattern drawing names |
| Pattern position | The position your pattern drawing states, sent with the enquiry |
| Deburring / finish | The finish the design states — an order field |
State the working pressure in the enquiry, with the pattern drawing or description. The perforated section's position in the string is the position the design states for it; raise any conflict between the pattern and the pressure in the enquiry itself.
Enquiring against a drawing
Send a drawing or a dimensioned pattern description: base size and grade, overall length and length convention, hole diameter, holes per row, number of rows, row spacing and the distance from a named end to the first row. Add the end finish and the service summary. Order perforated subs for the specific well — a single sub or a small set, as its drawing calls for — alongside plain tubing pup joints for the same completion, and keep them as separate RFQ lines, with the perforated item stated on its own line, with its drawing, apart from the plain joints.
Marking is an enquiry item on a perforated sub as it is on a plain pup joint: state the marking you need — measured length, pattern identification or both — in the enquiry, and the quotation will confirm whether it can be accepted and in what scope. If the well file needs the flow area recorded, ask for it in the quotation documents; it is calculated from the final pattern, not estimated from the request.
Can any tubing size be perforated?
Availability is not listed on this page: send the size and weight with the pattern in the enquiry, and ask for availability to be confirmed for it in the quotation.
Do perforated pup joints come in EUE and NUE?
If a perforated sub is confirmed for your pattern, send the pattern drawing with the enquiry, and ask for the end finish and the pattern's position against the upset and thread zones to be confirmed for the item in the quotation.
What pressure can a perforated pup joint hold?
This site publishes no pressure figure for a perforated joint. State your working pressure in the enquiry, with the pattern, and ask for the item to be checked against it before production.
Request a Quotation
Send your size, grade, thread and quantity. MOQ, packing and lead time are confirmed in the quotation for your exact specification — no generic promise replaces a written quote.