Skip to main content

Installation Instructions for the 2550 LJX Rotary Joint

Effective: June 1, 2022


Read all of the instructions before proceeding.

Refer to Kadant Johnson assembly drawing for part identification and to drawing A37640 for torque specifications. For easy identification, parts used in individual steps are often accompanied with their position in the assembly drawing [e.g. gasket (8B)]. Tighten all fasteners in a star pattern. Certified drawings are available upon request. Dimensions are for reference only and subject to change.


warning symbol

This safety symbol alerts you to risk of death or injury if the instructions are not followed. In all steps, death or injury may result if the machine is not de-energized, depressurized, cooled, and stopped. Death or injury may occur if the product is operated with a fluid type or at a pressure, temperature, or speed that do not meet its specifications. Death or injury may occur if heavy parts and pinch hazards are not handled properly. Follow your company’s safety procedures.

Step 1

Remove the existing rotary joint, syphon, and support rods from the roll.

Important: If reusing the journal flange, clean and inspect the bore where the nipple is inserted. If damaged, replace with a new flange.


Equipment must be cool and free of pressure.

Step 2

Install the new support rods.

Step 3

Remove the head, and gasket (8), from the rotary joint. 

Step 4

Remove the retention nut and multi-tab washer from the horizontal pipe. Apply anti-seize compound to the threads and tapered portion of the horizontal pipe.

Step 5

Carefully pass the horizontal pipe through the nipple until the key on the horizontal pipe is engaged with the keyway in the retention plate (31). Install the multi-tab washer and the retention nut on the horizontal pipe. Do not fully tighten the nut.

Note: The retention plate allows for multiple syphon locations. Refer to the assembly drawing for the correct location.

Step 6

Slide the nipple flange over the rotary joint nipple with the taper facing out. Place the split wedges into the recess of the nipple. Slide the nipple flange over the wedges.

Step 7

Place metal gasket (8Q) into the journal flange. Lift the rotary joint up and slide onto the support rods and into the journal flange. Secure to studs with nuts. An even gap of 1/8" to 3/16" (3 to 5 mm) should remain in between the journal flange and nipple flange. The syphon vertical leg will fall downward locking into place.

Step 8

Tighten the retention nut to 75 ft-lbs. Bend the multi-tab lock washer over the retention nut.

Step 9

Install the gasket (8) and head.

Step 10

For installations using a retaining plate, install a nut on each rod to the dimension on the assembly drawing. Install the retaining plate. Install the remaining lock washers and nuts to secure the retaining plate in place. Verify the set-up dimension on the assembly drawing.

Step 11

For installations using spacers, install a spacer on each rod. Install a nut on each rod to the specified set-up dimension on the assembly drawing. Install the lock washers and remaining nuts and lock into place.


The Kadant Johnson Warranty
Kadant Johnson products are built to a high standard of quality. Performance is what you desire: that is what we provide. Kadant Johnson products are warranted against defects in materials and workmanship for a period of one year after the date of shipment. It is expressly understood and agreed that the limit of Kadant Johnson’s liability shall, at Kadant Johnson’s sole option, be the repair or resupply of a like quantity of non-defective product.

Kadant Johnson rotary joints and accessories could be subject to European Pressure Equipment Directive 2014/68/EU (PED). Modifications or changes to rotary joints and/or accessories are only permitted upon approval of Kadant Johnson. Only genuine Kadant parts and original accessories will ensure the safety of these assemblies. The use of other than original parts voids the warranty and will lead to forfeiture of the declaration of conformity and will invalidate any liability for damages cause thereby.