The Nash CL is the workhorse of paper machine vacuum. It is a single-stage, two-lobe, cone-ported liquid ring pump built for high volumes of air and water at moderate vacuum, which is exactly what the forming and press sections demand. A typical machine runs a bank of CL pumps on a common header or dedicated services:

Each CL frame is offered in several sizes and speeds, so numbered variants of the models above (for example the 1001, 2002 or 3003 configurations) are common. We rebuild all of them.

Every CL rebuild follows the same seven-step repair process: tear down and inspection, materials inspection, remanufacturing, tolerances, assembly, painting and coating, and final inspection. On a CL pump specifically, that means:

• Tear down with a report. We measure rotor-to-cone clearance, cone runout, shaft runout and journal condition before anything is repaired, and send you the findings with the cause of failure.
• Rotor restoration. Rotors are cleaned, checked for cracks at the blade roots and shroud, built up or remachined at the cone bore, and balanced.
• Cone work. Cones are remachined true to the shaft centerline, or manufactured new in our shop when the original is beyond repair or no longer available.
• Body and head work. Corroded cast iron is welded and remachined. Where corrosion is chronic, we clad the water-contact surfaces in 304L or 316L stainless.
• Shaft, sleeves, bearings and seals. Shafts are repaired or manufactured new; sleeves are replaced; bearings and seals are new and meet OEM specifications.
• Clearance set and double-checked. The pump is assembled to original OEM tolerances and every clearance is verified before the heads are torqued.

The largest CL frames are heavy castings, and our shop is set up for them. The CL14000 body goes on a 120-inch vertical boring mill, rotors are pressed on and off with a 400-ton horizontal press, and shafts are turned on lathes with up to 240 inches between centers. Nothing on a CL rebuild leaves the building.

A CL exchange is a rebuilt pump shipped to you now, with your worn pump returned to us as the core. For a couch or uhle box pump that has failed mid-run, it is usually the fastest way to get the machine back to speed. Every exchange unit has been through the full seven-step process and is set to OEM tolerances, not simply cleaned and painted. See the exchange program (/repair-and-service/exchange-program) for how cores and shipping work.

We stock and machine CL series parts including cones, rotors, shafts, shaft sleeves, bearings, packing, mechanical seals and gaskets. When a part is obsolete, we reverse engineer it from your pump. See vacuum pump parts.