PTFE V-Packings for OEM, Valves, Pumps, Mixers and Agitators
PTFE V-packings are manufactured using either a manual lathe a CNC lathe, or a molding process. Each process has its advantages and disadvantages. In general molded parts are cheaper to produce, but require longer lead times and bigger commitments. Manual Lathes ar great for quick one-time sets, and CNC balances high production and quick turnaround times. AS&P offers all three methods of producing PTFE V-Packing. Other terms for this product is PTFE Vee or PTFE Chevron Packing.
There are three critical dimensions you need to know when looking for v-packing. You must know the Inside dimension (best taken off the shaft you are trying to seal), The outside dimension (best taken from the bore the set will be placed into) and the stack height. Generally slightly less than the height of the stuffing box.
Once we have those 3 dimensions, we will need to determine how many V-rings (also called pressure rings), are required to give you your desired stack height.
Finally, we will need to know if you need the male and female (top & bottom) to complete the set. Many pumps and valves come with the make and female made from metal already.
Are Exceptional in Chemical Applications, Cyrogenic applications, Clean service (FDA) applications. Because PTFE has the lowest coeffiecient of friction, it lowers stem drag allowing valves to turn easier. If your looking for a less expensive option we also offer other materials such as Nitrle, Viton, Neoprene, Grafoil
Standard Sizes Available:
We supply both molded and machined PTFE parts. Custom sizes to match competitor styles are available. Please specify I.D. / O.D. and stack height desired when ordering.
V-Packing sets consist of male & female adaptors with V-shaped pressure rings inbetween. Some equipment come with the male and female adaptors made of metal. The V-Pressure rings provide the sealing. The number of pressure rings determines the amount of pressure the set will contain. We provide molded or machined PTFE sets. Molded PTFE V rings are provided for large quantity orders (but require mold costs), while CNC produced sets elimate the need for a mold, but are more expensive to produce due the PTFE inside and outside dimension being cut away. Molded parts have no wasted PTFE. CNC parts are made from Bar stock or tube (to minimize waste).
Installing V-Packing correctly is simple if you remember one thing, the V-packing acts like a parachute. The pressure (air, water, oil, chemical etc.) should be under the Vee. The pressure spreads the Vee to the Outside and inside dimensions creating the seal. In cases of critical sealing you would not want the Vee to completely loose tension. To overcome this issue adding a spring load under the male adaptor works. The spring solution can be designed using a single spring, multiple springs or even an elastomer which can be in the shape of replaceable o-rings.
- Soot Blower Packing
- Other materials are also available
- V-Packing installation instructions
Rubber & Fabric V-Packing
The above set is an example of our v-pressure rings combined with equipment supplied metal end rings (Aluminum bronze in this example).
Molded PTFE V-packing
When PTFE is molded it will often have a shiny surface. That and the lack of very fine cutting lines left by a lathe can help you tell how they were made.
What are the most common applications for V-Packing?
V-Packing or Vee Packing if you prefer is commonly used in valves, reciprocating Pumps, centrifugal pumps, mixers, agitators, and actuators. The industries they are used in include but are not limited to food (PTFE is FDA application compatible), chemical (PTFE has a 0-14 ph range), oil, gas, pulp and paper, water, wastewater, power generation, the list goes on. Many of the PTFE V’s we sell go into original equipment manufacturers’ products.