Product Overview

The Junchi (SANMON) PTFE Chevron Packing Set is a premium sealing solution for reciprocating and slow-rotating shafts in oilfield pumps, valves, compressors, and process equipment. The chevron (V-ring) design consists of multiple stacked PTFE rings with an angular cross-section that creates a self-energizing seal under pressure. As system pressure increases, the V-rings expand radially, tightening the seal against both the shaft and the housing bore. This dynamic response ensures effective sealing across a wide range of operating pressures without excessive friction or shaft wear.

Manufactured from virgin PTFE and filled PTFE compounds (carbon-filled, glass-filled, or bronze-filled), our chevron packing sets offer exceptional chemical compatibility, low coefficient of friction (0.05-0.08), and wide temperature range. Each set includes a header ring (top adapter), multiple V-rings (sealing elements), and a female adapter (bottom ring) configured as a complete assembly for direct installation. All components are precision-machined in our Tianjin facility and undergo dimensional verification before packaging.

Technical Specifications

Applications

• Mud Pump Sealing: Piston rod and plunger packing for triplex and duplex mud pumps used in drilling operations, providing long service life with abrasive drilling fluids.

• Valve Stem Packing: Gate Valve, ball valve, and globe valve stem sealing in wellhead, pipeline, and process applications where fugitive emission control is required.

• Chemical Injection Pumps: Plunger packing for metering and injection pumps handling corrosive chemicals including acids, inhibitors, and methanol.

• Compressor Rod Packing: Reciprocating compressor piston rod sealing for gas gathering, gas lift, and process compression applications.

• Hydraulic Cylinders: Rod and piston seals for hydraulic systems on drilling rigs, BOP control systems, and well servicing equipment.

Advantages

• Self-Adjusting Seal: V-ring geometry automatically expands under pressure to compensate for wear and thermal expansion, maintaining sealing effectiveness without manual adjustment.

• Universal Chemical Resistance: PTFE is virtually inert to all chemicals, acids, solvents, and process fluids encountered in oilfield operations, eliminating material compatibility concerns.

• Wide Temperature Range: Maintains sealing performance from cryogenic temperatures (-200 deg C) to extreme heat (260 deg C), covering all oilfield operating scenarios.

• Low Friction: PTFE is inherently low friction coefficient reduces shaft wear, lowers drive power consumption, and eliminates stick-slip behavior in control valve applications.

• No Lubrication Required: Self-lubricating PTFE material operates dry or with process fluid lubrication, eliminating the need for external grease or oil lubrication systems.

• Long Service Life: Properly installed chevron sets typically outlast conventional braided packing by 3-5 times, reducing maintenance frequency and downtime costs.

Why Choose SANMON

SANMON has developed significant expertise in PTFE processing and sealing product manufacturing at our Tianjin facility. Our sealing division utilizes computer-controlled PTFE compression molding presses capable of achieving precise density and dimensional control, precision CNC lathes for post-molding machining, and automated inspection systems including laser micrometers and coordinate measuring machines (CMM) for dimensional verification. We maintain an extensive mold library covering standard shaft sizes and can produce custom configuration sets for non-standard equipment. Our material science team works with you to select the optimal PTFE compound (virgin, carbon-filled, glass-filled, or bronze-filled) based on your specific pressure, temperature, speed, and media requirements. Every packing set undergoes dimensional inspection and visual quality check before packaging in sealed, labeled bags for contamination-free storage. With competitive pricing, rapid turnaround on standard sizes, and comprehensive technical support, Junchi/SANMON provides reliable, cost-effective sealing solutions to the global oil and gas industry.

FAQ

Q: How many V-rings should be used in a set?
A: Typically 3-5 V-rings are used depending on the pressure rating and stuffing box depth. Higher pressures require more V-rings. Our standard sets include 4 V-rings, which covers most applications.

Q: Can virgin PTFE and filled PTFE rings be mixed in the same set?
A: Yes, it is common to use carbon-filled or bronze-filled rings for the pressure rings (first 1-2 rings) and virgin PTFE for the remaining rings, combining the strength of filled materials with the sealing finesse of virgin PTFE.

Q: Do PTFE chevron rings require spring loading?
A: A gland follower or spring-loaded gland is recommended to maintain light preload on the packing set at zero or low pressure, ensuring immediate sealing response when pressure increases.

Q: Are these suitable for high-speed rotating applications?
A: PTFE chevron packing is primarily designed for reciprocating and slow-rotating applications (below 2 m/s). For high-speed rotating shafts, we recommend mechanical seals or lip seals.

Q: How should chevron packing be installed?
A: V-rings must be installed with the open side (concave) facing the pressure source. The header ring goes against the gland follower, and the female adapter goes at the bottom of the stuffing box. Proper orientation is critical for correct sealing function.