DOUBLE/SINGLE-LAYER STUFFING BOX SEAL POLISHED ROD API 11B

This is a request for an API 11B wellhead tool known as a double-layer Stuffing Box. This specific tool is used to seal off the Polished Rod at a pumping wellhead. It consists of a cone packing and a free-floating lubricated upper section that ensures self-alignment and prevents packing burnout. The stuffing box is designed to prevent leakage caused by fluid pressure.

There are two options available for the stuffing box: single pack and double pack. The materials used for the cap, glands, body, base, and bottom are either 1045/4130 casting steel or ductile iron, depending on customer demand. The bottom of the stuffing box features API gauged threads of tubing EUE or LP.

These stuffing boxes are suitable for rod sizes 1", 1-1/8", 1-1/4", 1-1/2", and 1-3/4". They have a simple structure, are easy to install and maintain, and ensure effective sealing through single packing, double packing, or even triple packing.

The stuffing box for the polished rod consists of a cross shell, seal gate valves, sealing pin, sealing cap, and rubber packing. The bottom of the stuffing box can be connected using threads, flanges, or clamps. This device reduces wear on the polished rod and improves oil recovery.

Key characteristics of the stuffing box are that it has a unique misaligning feature that reduces the need for precise alignment with the Pumping Unit, it is equipped with cone packing, and it has a lubricated upper gland (LUG) with a grease zerk for rod lubrication. Optional components include an oil reservoir gland (ORG) and an anti-pollution adapter (APA). The stuffing box has a simple structure, making it easy to install, and it is widely used in the industry.

The specification of the stuffing box includes a working pressure of 1500 psi, connecting threads of 2-7/8" EUE, 3" LP, or 3-1/2" EUE, and a working temperature of 149ºC for H2S & CO2 below 1% or 120ºC for H2S below 2% & CO2 below 10%. It performs well in terms of mechanical tear and abrasive resistance and in steam environments.

The stuffing box cone packing is available in sizes for polished rods measuring 1-1/8", 1-1/4", and 1-1/2". It comes in a set of four (three top cones and one bottom cone) and also includes one bottom cone.

During installation and usage, it is important to inspect and clean the device thoroughly before installation. Pay attention to the size of the polished rod to ensure compatibility with the valve specifications. When installing, adjust the seal compression force until there is no leakage. It is recommended to make adjustments in small increments to prevent a decrease in service life.