Valve Packing Installation Steps

- May 16, 2018-

The effective sealing of the pump and the valve depends on the overall condition of the individual components, and it is believed that the equipment needed to replace the packing has been effectively isolated in accordance with the site and system. The correct installation of the packing is also the key to ensure the sealing effect.

1, choose the packing. Ensure that the packing used is selected to meet the operating conditions required by the system and equipment; based on the measurement records, calculate the cross-sectional area of the packing and the number of packing rings required; check the packing to ensure that it is not defective; before installation, make sure Equipment and packing are clean.

2. The packing installation tool needs special tools for packing and pre-tightening the gland nuts with fasteners. In addition, it is also necessary to use standard safety facilities and comply with relevant safety regulations. Before installing the packing, first of all be familiar with the following equipment: cutting machine for checking packing ring, calibration torque wrench or wrench, helmet, inside and outside caliper, fastener for lubricant, mirror, packing remover, cutting plate Root tools, vernier calipers, etc.

3, cleaning and inspection. Slowly loosen the gland nut, release any residual pressure in the packing assembly, remove all old packing, thoroughly clean the shaft/rod packing box, check the shaft/rod for corrosion, dents, and scratches. Or excessive wear; Check whether other parts have burrs, cracks, wear, they will reduce the life of the packing; Check the packing box if there is excessive clearance, and shaft / rod eccentricity; Replace parts with larger defects; Examine the old packing as a basis for failure analysis to find out why the packing has failed early.

4, measurement and recording. Record the shaft/rod diameter, packing box diameter and depth, and record the distance from the bottom to the top of the stuffing box when the ring is sealed with water.

5, the preparation of the ring. Braided packing is wound around a suitable sized shaft, or a calibrated packing ring cutter is used; the packing is cut neatly (either square) or mitered (30-45 degrees), one at a time, as required Ring, and use the shaft or valve stem to check the size is appropriate. Mold the packing to ensure that the ring is precisely sized to fit the shaft or stem. If necessary, cut the packing ring according to the packing manufacturer's instructions or requirements.

6, install the packing. Carefully install one packing ring at a time and place each ring around the shaft or stem. Before installing the next ring, make sure the ring is fully seated in the stuffing box. The next ring should be staggered, at least. 90 degrees apart, generally requiring 120 degrees. After the first ring is installed, tighten the nut by hand and press the cover evenly. If there is a water seal ring, check that the distance between the packing and the top of the stuffing box is correct. At the same time ensure that the shaft or valve stem can rotate freely.