Dormakaba 75233 3/4" Offset Hung Full Mortise Intermediate Pivot, 3 Hour Rated Fire Door

Yes. The 75233 offset pivot is fire rated, with a 3 hour rating, so it can go on an opening carrying up to a 3 hour label. That is the spec that separates it from a lot of intermediate pivots, which are non-rated. Among the pivots we stock, Ives 7215F and the Ives 7212 and 7215 offset pivot sets are also fire rated, while the Hager 253 reinforcing pivot, Hager 497 bottom pivot, and the Kaba Ilco IP-10, IP-12, IP-22 and IL-OP-10 aluminum door pivots are not.

Up to 660 lbs. That is a heavy duty commercial rating, enough for solid core wood, hollow metal, and lead lined or heavy institutional leaves. For reference on the lighter end of what we stock, the Ives 7212 offset pivot set is a 200 lb capacity set and the Ives 7215 is 500 lb. If your leaf is over 660 lbs you are outside what the 75233 is rated to carry and you need to step up, not just add pivots.

Handing matters. The 75233 is a handed intermediate pivot and is ordered LH or RH, so you have to know which way the door swings before you buy. If you are pivoting a pair, that is one of each. A non handed alternative we stock is the Kaba Ilco IP-12 Series intermediate pivot, though that one is for aluminum doors and frames and is not fire rated.

It is the intermediate pivot only, one component of an offset hung set. An offset hung door runs on a top pivot at the head, a bottom pivot or floor closer spindle at the sill, and one or more intermediate pivots up the hinge stile to carry load and keep the leaf from racking. So the 75233 supplements the top and bottom hardware, it does not replace it. If you want top and bottom supplied together instead, the Ives 7212 and 7215 are sold as offset pivot sets.

Full mortise. Both leaves of the 75233 let into prepped pockets, one in the door edge and one in the frame rabbet, so the door and frame have to be machined for it. If your door is already hung on butts and you only need to reinforce the top of the leaf without cutting a new mortise, a full surface reinforcing pivot such as the Hager 253 for 4-1/2 inch wide hinges is the different animal you want, though that one is not fire rated.

It is built for standard commercial door and frame construction and is a heavy duty full mortise unit rated to 660 lbs, which is a hollow metal or solid core application, not a narrow aluminum stile. For aluminum doors and frames, the Kaba Ilco intermediate pivots are the ones made for that construction: the IP-10 Series, the IP-12 Series non handed, and the IP-22 Series, plus the IL-OP-10 Series 1/8 inch recessed pivot set for Arch and Vistawall. Those are standard duty and not fire rated, so if the storefront opening carries a label, the aluminum pivots are not the answer.

They do different jobs in the same opening. The Hager 497 is a heavy duty bottom pivot hinge with a ball bearing, forged bronze full mortise, and it carries the weight of the door at the sill. The Dormakaba 75233 is an intermediate pivot, the part mounted between the top and bottom pivots to steady a tall or heavy leaf and share the load. Ordering one when the job called for the other leaves the opening incomplete. Note also that the Hager 497 is not fire rated, while the 75233 carries a 3 hour rating.

The Ives 7215F is the nearest peer. It is a stainless steel 3/4 inch offset pivot set with a top header mount, rated for 500 lb doors and fire rated. The Dormakaba 75233 is a 3/4 inch offset hung full mortise intermediate pivot, heavy duty, rated for doors up to 660 lbs and carrying a 3 hour fire rating. Both share the 3/4 inch offset geometry, so the door and frame prep line up on the same centerline. The difference is scope: the 7215F is a complete pivot set including the header component, while the 75233 is the intermediate pivot that carries load between the top and bottom pivots on a tall or heavy leaf.

No. The Hager 253 is the part for that condition: a full surface reinforcing pivot for 4-1/2 inch wide hinges, zinc plated, heavy duty, for 1-3/4 inch thick doors. It surface mounts to back up a hinge hung door. The Dormakaba 75233 is a full mortise intermediate pivot for an offset hung door, so it assumes the leaf is already swinging on pivots rather than butts. Note the Hager 253 is not fire rated, so on a rated opening confirm the reinforcement approach with the door manufacturer.

The offset is where the pivot point sits relative to the door face. A 3/4 offset hangs the leaf with the pivot point 3/4 inch off the face, so the door swings clear of the frame and you can run a butt style seal and a standard frame stop. Center hung puts the pivot on the door centerline, so the leaf rotates in place and both edges move, which is what double acting and full glass entries usually need. Dormakaba pivot sets are made for center hung, 3/4 offset, and 1-1/2 offset applications, so pick the family that matches how the opening was prepped. The 75233 is 3/4 offset and mortises into the door and frame.

The intermediate pivot is what keeps a heavy leaf from sagging and racking between the top and bottom pivots, so tall and heavy doors get more than one, spaced up the hinge stile. Each 75233 is a single handed pivot, so a door taking two intermediates is two of the same hand, and a pair of doors is two of each hand. Confirm the count against the door manufacturer's requirement for the leaf weight and height, since the 75233 itself is rated to carry up to 660 lbs.

Commercial, heavy duty. The 75233 is specified for commercial construction and carries up to 660 lbs on a 3 hour rated fire door, which is the class of hardware you put on hospital, school, and multi family stair and corridor openings where the leaf is heavy and the label has to hold.

The Kaba Ilco IP-12 Series intermediate pivot is non handed, which lets one part number cover both swings on aluminum doors and frames. It is standard duty and not fire rated. The Dormakaba 75233 is handed, ordered as left hand or right hand, and is heavy duty with a 3 hour fire rating. For a facility standardizing across rated openings, the handing has to be specified per door; the non handed IP-12 only removes that step on non rated aluminum openings.

Two: 626 satin chrome and 613 satin bronze oil rubbed, each available left hand or right hand. On an offset hung opening the intermediate pivot is mostly buried in the door edge, so the usual reason to care is matching the visible top and bottom pivot plates and the closer on the same leaf. 626 is the common commercial match for satin chrome and satin stainless trim, 613 for dark bronze and oil rubbed suites.

It is a mechanical pivot with no electrical function, so it will not carry power to an electrified lock or an exit device on the leaf. If the opening needs power transfer, that is a separate electric power transfer or door loop specified alongside the pivot hardware.

The Ives 7215F is a stainless steel 3/4 inch offset pivot set, while the Ives 7212, 7212V and 7215 sets are brass. The Dormakaba 75233 comes in 626 satin chrome and 613 satin bronze oil-rubbed. If a facility is standardizing on a satin chrome look across an opening, the 626 finish on the 75233 is the match; the stainless 7215F is the choice where the specification calls for a stainless component.