| Product | Type | Style | Rating |
|---|---|---|---|
| Heat Exchanger | Plate & Frame | Gasketed | 350 PSI / 410°F |
The original Accu-Therm, and the unit most of this line is built from. It handles simple fluids, viscous solutions and light particulates in the same frame, with the plate pattern doing the tuning.
Twenty-six cataloged frame sizes, AT4 through AT161FF. The table further down carries every one of them with the dimensions and ratings that separate them.
Request a Quote| PRODUCT | CONSTRUCTION | MATERIALS | SUPPLY |
| Accu-Therm Plate Heat Exchanger | Mueller factory built | 304 / 316 stainless | New equipment |
The standard Accu-Therm is an industrial workhorse. It appears in HVAC plant rooms, chemical process trains, oil and gas facilities, refrigeration systems and food plants, and the reason is that one frame family covers an enormous range of duty simply by changing plate count, plate pattern and materials.
Seven corrugation patterns. The plate pattern sets the balance between thermal efficiency and pressure drop. A high-theta plate extracts more heat per pass and costs more pressure drop; a low-theta plate does the reverse. Because patterns can be mixed within one pack, the pack can be tuned rather than compromised.
Sizes and connections. Individual plate heat transfer areas run from 0.5 up to 51 square feet, so the same design principle serves a small skid and a large plant utility duty. Studded ports are standard and can be fully lined to protect the frame from erosion and corrosion. Lap-joint, weld-neck, ferrule and Victaulic connections are available and can be mixed on one unit.
Testing and inspection. Each circuit is tested independently at full design pressure before the unit ships. In service, removing the compression bolts and sliding back the movable end frame exposes 100 percent of the heat transfer surface for inspection.
Part numbers. Every cataloged model, with the dimensions and ratings that separate them: Accu-Therm Series Part Numbers (41 part numbers).
This is where most of the engineering happens and where most of the difference in a quotation comes from. Two units with the same surface area can behave very differently depending on the corrugation depth and angle.
Give us the allowable pressure drop on each side along with the thermal duty. Without it, the software will happily produce a unit that makes the temperature and cannot be pumped through, or a unit with far more surface area than the duty needs.
It is common for one side of a unit to be sanitary and the other to be plant utility. Ferrule connections on the product side and flanged connections on the water side is a normal, sensible arrangement and costs less than making everything sanitary.
Studded ports are the standard arrangement and can be lined where the fluid is erosive or the frame material would otherwise be attacked.
The Accu-Therm number is the frame, not the unit. An AT20 with forty plates and an AT20 with four hundred are the same part number and very different exchangers — the frame sets the plate size, the port size and the maximum pack length, and the plate count inside it sets the duty.
Reading the number. The digits are a size designation, not a plate count and not a capacity. AT4 is the smallest frame in the range and AT161 the largest. A letter suffix adds a construction: W for semi-welded, FF for free-flow, DW for double-wall, SAN for sanitary.
What to send us. If you are replacing a unit, the part number off the nameplate plus the plate count is enough to quote a match. If you are specifying a new one, send the duty instead and let the frame fall out of the calculation.
The surface area column gives the span between the minimum and maximum plate count that frame accepts. Where you land inside that range is the selection. A frame quoted near the top of its range has no headroom left, which is worth knowing at purchase rather than at the next debottleneck.
Maximum flow is the frame's port limit, not a duty. Hitting it means the port velocity is at the top of what the design allows, and pressure drop will be doing the same.
The frame type code in the table is the style, and it decides how the unit mounts and how far the pack can grow. C is the compact cantilever frame, for the small sizes and tight plant rooms. F is the intermediate frame with a support column. B is the full frame with the longest carrying bar and the largest plate counts.
Some sizes are offered in more than one style, which is why the column sometimes reads "C, F" or "C, F, B". If pack headroom matters to you — and it should, because adding plates later is far cheaper than buying a second unit — say so and we will quote the frame that leaves you room.
It is the shop test pressure, 1.3 times the maximum allowable working pressure, applied to each circuit separately before shipment. Testing one side at a time proves the plates hold between the two streams as well as against atmosphere. If a field hydrotest is planned after installation, keep it at or below that figure, because overpressure can deform plates and unseat gaskets.
The design can be built for metal temperatures down to -20°F, but most units are stamped with a 32°F minimum design metal temperature. If a glycol stream or an outdoor winter startup can pull the metal below freezing, say so at order. A lower MDMT has to be specified and stamped in from the start, and it cannot be claimed after the unit is built.
Multi-pass sends a stream back through the pack more than once, which raises velocity and thermal length when one side has a small flow or a long temperature change. The cost is that connections end up on the movable frame as well as the fixed one, so pipework at that end has to come off before the pack can open. Single pass keeps every connection on the fixed frame, which is why it is the default.
These are for chemistry that 316 cannot survive and titanium does not suit, which mostly means acids. SMO 254 is a high-molybdenum stainless with far better chloride pitting resistance than 316, while C-276 is a nickel alloy for strong reducing and oxidizing acids. Both carry a real price premium, so send the full stream analysis and temperature and let the material follow from that.
The frame and plates are rated to 410°F, but every elastomer has a lower ceiling, and the standard compounds stop between 302°F and 329°F. The gasket is therefore the real temperature limit of a gasketed Accu-Therm. A stream above that window calls for a different construction, not a tougher seal, so give us the peak temperature on each side, upset conditions included.
| Part Number | Frame | Plate H | Plate W | Port | Surface Area | Max Flow | Also Written |
|---|---|---|---|---|---|---|---|
| AT4 | C | C Frame (Cantilever) | 23" | 8" | 1" | 15 - 50 sq ft | 80 | AT 4, AT-04, AT-4, AT04 |
| AT5 | C | C Frame (Cantilever) | 31-1/8" | 7-1/2" | 1" | 18 - 70 sq ft | 80 | AT 5, AT-05, AT-5, AT05 |
| AT10 | C, F | C Frame (Cantilever), F Frame (Intermediate) | 37" | 14" | 2" | 13 - 273 sq ft | 200 | AT 10, AT-10 |
| AT20 | C, F, B | C Frame (Cantilever), F Frame (Intermediate), B Frame (Beam) | 56" | 24" | 3" | 28 - 1,279 sq ft | 450 | AT 20, AT-20 |
| AT35 | C, F | C Frame (Cantilever), F Frame (Intermediate) | 52" | 13-1/2" | 2" | 30 - 600 sq ft | 200 | AT 35, AT-35 |
| AT40 | F, B | F Frame (Intermediate), B Frame (Beam) | 70-1/4" | 27" | 4" | 99 - 2,292 sq ft | 800 | AT 40, AT-40 |
| AT55 | F, B | F Frame (Intermediate), B Frame (Beam) | 77-1/2" | 18-1/2" | 4" | 80 - 1,600 sq ft | 800 | AT 55, AT-55 |
| AT60 | F, B | F Frame (Intermediate), B Frame (Beam) | 82-1/8" | 27" | 4" | 110 - 2,500 sq ft | 800 | AT 60, AT-60 |
| AT75 | B | B Frame (Beam) | 75-5/8" | 25-1/2" | 6" | 120 - 2,900 sq ft | 1800 | AT 75, AT-75 |
| AT80 | B, LB, RB | B Frame (Beam), LB Frame, RB Frame | 85" | 36" | 6" | 181 - 4,186 sq ft | 1800 | AT 80, AT-80 |
| AT95 | B | B Frame (Beam) | 107-3/4" | 25-1/2" | 6" | 170 - 4,000 sq ft | 1800 | AT 95, AT-95 |
| AT120 | B | B Frame (Beam) | 104-1/2" | 36" | 6" | 230 - 5,200 sq ft | 1800 | AT 120, AT-120 |
| AT130 | B | B Frame (Beam) | 106-3/4" | 43" | 10" / 12" | 413 - 9,804 sq ft | 6600 | AT 130, AT-130 |
| AT150 | B | B Frame (Beam) | 109-3/8" | 34-1/2" | 8" | 300 - 7,000 sq ft | 3200 | AT 150, AT-150 |
| AT156 | B | B Frame (Beam) | 87-1/2" | 34-1/2" | 8" | 240 - 5,600 sq ft | 3200 | AT 156, AT-156 |
| AT165 | B | B Frame (Beam) | 126-3/8" | 45-3/8" | 14" | 500 - 12,000 sq ft | 9500 | AT 165, AT-165 |
| AT180 | B | B Frame (Beam) | 126" | 56" | 14" | 600 - 14,000 sq ft | 9500 | AT 180, AT-180 |
| AT250 | B | B Frame (Beam) | 134" | 57" | 16" / 20" | 972 - 17,309 sq ft | 17300 | AT 250, AT-250 |
| AT402 | C, F | C Frame (Cantilever), F Frame (Intermediate) | 39-1/4" | 27" | 4" / 6" | 16 - 106 sq ft | 1150 | AT 402, AT-402 |
| AT405 | C, F, B | C Frame (Cantilever), F Frame (Intermediate), B Frame (Beam) | 56" | 27" | 4" | 48 - 1,495 sq ft | 800 | AT 405, AT-405 |
| AT426 | C, F | C Frame (Cantilever), F Frame (Intermediate) | 43-3/4" | 18-1/2" | 4" | 40 - 900 sq ft | 800 | AT 426, AT-426 |
| AT805 | B | B Frame (Beam) | 63" | 36" | 6" | 105 - 2,440 sq ft | 1800 | AT 805, AT-805 |
| AT510 | B | B Frame (Beam) | 90" | 30" | 6" | 200 - 4,400 sq ft | 1800 | AT 510, AT-510 |
| AT1306 | B | B Frame (Beam) | 84-3/4" | 43" | 10" / 12" | 262 - 6,209 sq ft | 6600 | AT 1306, AT-1306 |
| AT1309 | B | B Frame (Beam) | 99-1/2" | 43" | 10" / 12" | 363 - 8,622 sq ft | 6600 | AT 1309, AT-1309 |
| AT2508 | B | B Frame (Beam) | 120" | 57" | 16" / 20" | 860 - 15,308 sq ft | 17300 | AT 2508, AT-2508 |
| AT4P | C | C Frame (Cantilever) | 23" | 8" | 1" | 15 - 50 sq ft | 80 | AT 4P, AT-04P, AT-4P, AT04P |
| AT20P | C, F, B | C Frame (Cantilever), F Frame (Intermediate), B Frame (Beam) | 56" | 24" | 3" | 28 - 1,279 sq ft | 450 | AT 20P, AT-20P, AT20 P, AT20-P |
| AT40M | F, B | F Frame (Intermediate), B Frame (Beam) | 70-1/4" | 27" | 4" | 99 - 2,292 sq ft | 800 | AT 40M, AT-40M, AT40 M, AT40-M |
| AT40P | F, B | F Frame (Intermediate), B Frame (Beam) | 70-1/4" | 27" | 4" | 99 - 2,292 sq ft | 800 | AT 40P, AT-40P, AT40 P, AT40-P |
| AT40L | F, B | F Frame (Intermediate), B Frame (Beam) | 70-1/4" | 27" | 4" | 99 - 2,292 sq ft | 800 | AT 40L, AT-40L, AT40 L, AT40-L |
| AT60M | F, B | F Frame (Intermediate), B Frame (Beam) | 82-1/8" | 27" | 4" | 110 - 2,500 sq ft | 800 | AT 60M, AT-60M, AT60 M, AT60-M |
| AT75P | B | B Frame (Beam) | 75-5/8" | 25-1/2" | 6" | 120 - 2,900 sq ft | 1800 | AT 75P, AT-75P, AT75 P, AT75-P |
| AT75X | B | B Frame (Beam) | 75-5/8" | 25-1/2" | 6" | 120 - 2,900 sq ft | 1800 | AT 75X, AT-75X, AT75 X, AT75-X |
| AT80M | B, LB, RB | B Frame (Beam), LB Frame, RB Frame | 85" | 36" | 6" | 181 - 4,186 sq ft | 1800 | AT 80M, AT-80M, AT80 M, AT80-M |
| AT80P | B, LB, RB | B Frame (Beam), LB Frame, RB Frame | 85" | 36" | 6" | 181 - 4,186 sq ft | 1800 | AT 80P, AT-80P, AT80 P, AT80-P |
| AT120M | B | B Frame (Beam) | 104-1/2" | 36" | 6" | 230 - 5,200 sq ft | 1800 | AT 120M, AT-120M, AT120 M, AT120-M |
| AT130M | B | B Frame (Beam) | 106-3/4" | 43" | 10" / 12" | 413 - 9,804 sq ft | 6600 | AT 130M, AT-130M, AT130 M, AT130-M |
| AT156X | B | B Frame (Beam) | 87-1/2" | 34-1/2" | 8" | 240 - 5,600 sq ft | 3200 | AT 156X, AT-156X, AT156 X, AT156-X |
| AT405M | C, F, B | C Frame (Cantilever), F Frame (Intermediate), B Frame (Beam) | 56" | 27" | 4" | 48 - 1,495 sq ft | 800 | AT 405M, AT-405M, AT405 M, AT405-M |
| AT805M | B | B Frame (Beam) | 63" | 36" | 6" | 105 - 2,440 sq ft | 1800 | AT 805M, AT-805M, AT805 M, AT805-M |
41 part numbers.
Sanitary duty asks two things at once: hit the thermal number, and prove afterward that the equipment can be...
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Some fluids attack gaskets. Welding pairs of plates into cassettes puts those fluids inside a welded boundary...
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Conventional plates block on fibers and particulates. The Free-Flow plate opens the channel up, which lets it...
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