Dual 140 mm Fan to 150 mm Metric Duct Shroud

Description

Dual 140 mm fan to 150 mm metric duct shroud

A dual 140 mm fan to 150 mm duct shroud sits at the intersection of two things the market handles badly: the newer 140 mm fan generation of ASICs, and metric ducting. Miners moved to 140 mm fans to move the same air at lower fan speed, yet most shrouds on sale are still cut for 120 mm, and most of the world buys hose in millimetres and gets sold collars in inches.

It is fitment by geometry rather than by model badge: two 140 mm exhaust fans on a 140.0 mm pitch, 134.0 mm bore per fan with a 3.0 mm sealing land around each. Both fan columns merge inside one PETG body and converge into a 150 mm metric collar, the standard domestic extraction size across the metric world and the most widely stocked hose you can build a run out of.

What it fits: any dual 140 mm exhaust at 140.0 mm pitch

Miners with two 140 mm exhaust fans on a 140.0 mm pitch, exhausting into 150 mm metric flex duct. Check the fan, not the name on the lid: 140 mm fans are what the newer high-power generation uses, and the pitch is what decides whether a flange lands square.

For a flange drawn to the S21 Pro chassis itself, that family runs from the S21 Pro dual 140 mm to 6-inch shroud up to the S21 Pro 200 mm metric shroud. A 120 mm fan machine needs the dual 120 mm to 150 mm shroud instead.

How it installs

1. Sit the flange over both 140 mm exhaust fans, aligned on the fan screw pattern.
2. Drive the screws through the 5.0 mm flange holes and 5.424 mm slots, reusing the miner’s own large-head fan screws or adding a 9 mm or larger flat washer under your own.
3. Push 150 mm metric flex duct over the collar, past the 150.0 mm crest.
4. Clamp onto the 148.0 mm sealing land, then run the duct to a window port or inline fan.

Why the 140 mm capture matters

A 140 mm fan has substantially more blade area than a 120 mm one, which is why the newer machines use them: more area moves the same volume at lower rotational speed, and fan noise is dominated by tip speed. Bolt a 120 mm shroud over a 140 mm fan face and you mask the bore, adding a restriction right where the air leaves the blades. The bore here is 134.0 mm per fan with a 3.0 mm sealing land, so the fan discharges into open body rather than into a lip.

From there both columns merge before the transition to round. The collar is flex-over: crest at duct nominal, sealing land 2.0 mm under, at or below the male metric hardware a 150 mm hose expects, so a plain worm clamp does the whole job.

• Cut for the dual-140 generation: 140.0 mm pitch, 134.0 mm bore, 3.0 mm sealing land per fan.
• Keeps the fan bore clear so the extra blade area of a 140 mm fan is not masked at the outlet.
• Lands on real 150 mm metric duct rather than a 152.4 mm imperial collar.
• Seals by clamp on the 148.0 mm land, 150.0 mm crest as the stop.
• Leaves 8.62 mm of driver clearance at the tightest fan screw on a 300 mm wide body.
• One piece of PETG, which holds shape in exhaust heat that softens cheaper print plastics.

Specifications

Open source: a size the market skipped

Dual 140 mm and metric is the combination nobody stocks, so D-Central Technologies drew it and then published it. The design is ours — the 140.0 mm capture, the 134.0 mm bores, the 150.0 mm crest, all our own work — released under CC BY-SA 4.0 at the 3D models download center, free to download, modify, print and sell. Its card is at the dual 140 mm to 150 mm entry and the file is the dual-140 to 150 mm shroud bundle, holding the STL, the CC BY-SA 4.0 licence and the installation and safety guide. A part that does not exist commercially should at least exist as a file.

This listing is that file made real: produced to order in PETG in Montreal, Quebec, black or orange, shipped from Canada. It stays downloadable no matter what; a purchase, or support through the D-Central fund page, is what keeps sizes the market skipped getting drawn at all.

Works with

• Dual 140 mm Fan to 160 mm Metric Duct Shroud
• Dual 140 mm Fan to 200 mm Metric Duct Shroud
• Universal Dual 140 mm to 6″ Duct Shroud
• Antminer S19 / S21 Dual 120 mm to 150 mm Metric Duct Shroud
• 140 mm Intake Filter Ring

Full range: D-Central shroud and ducting system.

Frequently asked questions