Description
Are you interested in learning more about peek valve seat material? Contact us today to secure an expert consultation!
PEEK tube pipe is highly resistant to thermal degradation and attack by both organic and aqueous media. It resists creep and retains dimensional stability at high temperatures and pressures, making it ideal for use in seal backup.
Our PEEK sealing materials for rotary, reciprocating, and static applications are formulated to provide optimal performance and service life in your designs. Our offering ranges from virgin PEEK to precision blends that leverage the additive properties of carbon fiber, glass fiber, PTFE, and other fillers to meet specific temperature pressure, speed, and wear requirements.
SNC Plastic offer extruded PEEK round bar/rod and tube stock, and also a wide range of moulded PEEK tube pipe in sizes up to 1000mm+ in diameter.
We also can produce finished PEEK parts according to your requirements. Such as valve seat insert, seat ring for Trunnion Mounted Ball Valve, Slab Gate Valve, Expanding gate valve, Floating Ball valve…
The Basics of Ball Valve Seat and Seat Insert Materials
Ball valves play a critical role in controlling the flow of fluid and pressure within a pipeline, but their effectiveness and safety is only as good as the seat insert material used.
Ball Valves
Whether found in a petrochemical application where a leak could be environmentally devastating, or in a pharmaceutical laboratory where cleanliness and sanitation are critical, ball valve seats must be reliable and robust. A ball valve consists of the body of the valve, the body cap, the stem, the hollow ball, and the round ball valve seat.
The ball valve seat is responsible for sealing the fluid inside and uniformly distributing the seating stress. In soft seat ball valve designs, either an elastomer or polymer is used as the seal and are inserted into a metallic seat ring. This approach, as opposed to hard seat ball valves, is popular because it provides good sealing action, is lighter weight, and more cost effective.
PEEK Seals are among the most robust polymer seals available. PEEK exhibits extremely high tensile properties and low deformation under load. As a result, PEEK machined seals are very stable over an extended period of time, even in environments where pressure, temperatures, and chemicals place loads on the material
VALVE SEAT and seat insert MATERIAL SELECTION
SNC Plastic provide most suitable valve seat material solutions to your application.
Material Main Properties Notes/Applications Temperature Range Virgin Natural PEEK Excellent chemical resistance and mechanical properties at elevated temperatures. Unreinforced PEEK is a general purpose material noted for its high elongation and toughness. valve seats, seat inserts, back-up rings, sealings -40℃ to 260℃ Carbon fiber filled PEEK Offers increased strength, stiffness, and stability at high temperatures. Good wear resistance and thermal conductivity. Bearings, bushings, seals, thrust washers, valve plates -40℃ to 260℃ Glass fiber filled PEEK Gives designers the benefit of excellent compression strength and stiffness and reduced expansion rates. Excellent chemical resistance Suitable for use in parts which are exposed to high static loads over long periods in high temperature conditions. -40℃ to 260℃ Bearing Grage PEEK Excellent combination of low friction, low wear, high limiting PV, low mating part wear, and easy machining Bearings, bushings, pump wear rings, seals, Thrust washers… -40℃ to 260℃ PTFE filled PEEK Higher lubricity than Virgin PEEK. It also has a low tendency to abrade counter surfaces, even when parts are subjected to temperatures between 100°C and 260°C. Suited to sealing applications where start-stop or rotary motions are involved at higher RPMs -40℃ to 260℃
PolyEtherEtherKetone (PEEK)
Maintains wear resistance and mechanical strength up to 260℃ continuous use.
PEEK is the performance material of choice for aggressive environments such as high temperatures, wet processes, and heavy loads. It combines exceptional wear, chemical and moisture resistance with very high strength, dimensional stability and stiffness. PEEK can be continuously exposed to hot water or steam with no distortion, corrosion or galling.
Unreinforced PEEK is a general purpose material noted for its high elongation and toughness. Glass fiber-reinforced PEEK offers increased strength, stiffness and stability at high temperatures, while carbon fiber-reinforced PEEK gives designers the benefit of excellent compression strength and stiffness and reduced expansion rates. PEEK is easily machined to precise tolerances.
Properties
Applications
Industries
Material Data Sheet
PEEK (polyetheretherketone) is a high-performance engineering plastic with outstanding resistance to harsh chemicals, and excellent mechanical strength and dimensional stability.
Item Test Standard or Instrument Unit PEEK-N PEEK-GF30 PEEK-CF30 PEEK-HPV Physical Properties Color – Natural or Black Natural or Black Black Black Density ISO 1183-1 g/cm3 1.3±0.01 1.5±0.01 1.4±0.01 1.43±0.01 Water Abs. (25℃.24Hrs) ISO 62 % 0.5 0.11 0.06 0.06 Mould shrinking percentage 3mm,170℃, Flow direction % 1.2 0.4 0.1 0.3 Perpendicular to flow direction % 1.5 0.8 0.5 0.5 Thermal Properties Melting point ISO 11357 ℃ 343 343 343 343 Distortion temperature ISO 75-1/-2 ℃ 163 315 315 293 Continuous using temperature UL 74685 ℃ 260 260 260 260 Glass transition temperature ISO 11357 ℃ 143 – – – Machanical Properties Tensile strength(23℃) ISO527-2/1B/50 Mpa 100 155 220 134 Tensile elongation(23℃) ISO527-2/1B/50 % 34 2 1.8 2.2 Bending strength(23℃) ISO 178 Mpa 163 212 298 186 Compressive strength(23℃) ISO 604 Mpa 118 215 240 150 Lzod impact strength( no gap) ISO 180/U KJm-2 No crack 51 46 32 Rockwell hardness ISO 2039-2 99 103 107 102 Friction coefficient – μ 0.30-0.38 0.38-0.46 0.28 0.18 Electrical Properties Dielectric strength IEC 60243-1 KV/mm 18 19 Dielectric constant IEC 60250 3.2 3.3 Surface resistivity IEC 90093 Ω 1015Ω 1015Ω 3×106Ω 5×106Ω Miscellaneous Data Flammable level UL 94 V-0@mm 1.5 1.5 1.5 0.75 NOTE: *The data stated above are typical values intended for reference and comparison purposes only. *The data should not be used as a basis for design specifications or quality control. *The information is provided as a guide to the best of our knowledge and given without obligation or liability. *Testing under individual application circumstances is recommended. * PEEK-N, Natural (Unfilled) PEEK * PEEK-GF30, 30% Glass Filled PEEK * PEEK-CF30, 30% Carbon Filled PEEK * PEEK-HPV, 10% Carbon + 10% Graphite + 10% PTFE filled PEEKINTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS
FIRST NAME
*
LAST NAME
*
*
MESSAGE
*
ADDITIONAL DETAILS
Thanks. We have received your request and will respond promptly.
Log In
Are you an
Engineering professional?
Join Eng-Tips Forums!
If you are looking for more details, kindly visit surface safety valves.
*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.
Promoting, selling, recruiting, coursework and thesis posting is forbidden.
Eng-Tips Posting Policies
PEEK vs Carbon Filled PTFE for ball valve seats
3
thread378-380219 Forum Search FAQs Links MVPsForum
Search
FAQs
Links
MVPs
(Mechanical)
(OP)
17 Feb 15 02:11Our application is thermal fluid (Paratherm HE) at 400°F and 120PSI.
We are looking at 2" ball valves with either PEEK or carbon filled PTFE seats. Is one a clear winner for any reason? Both seem good to about 500°
(Mechanical)
17 Feb 15 02:44PEEK has come down a lot in price since the last time I looked at it. A 2-1/2" dia rod, probably about the right size to make a 2" ball seat, is only a little over $400 a foot, per professionalplastics.com . They don't provide an online price for carbon/PTFE. If performance is otherwise equal (I have no opinion about that), then price may become a valid selector.What will you do for a stem seal?
Mike Halloran
Pembroke Pines, FL, USA
(Mechanical)
(OP)
17 Feb 15 11:12They are proposing expended graphite for the stem seal
2
moltenmetal(Chemical)
17 Feb 15 13:22PEEK will survive these conditions long term- it has an upper service temperature limit in seats and seals somewhere nearer to 600F (315 C). It does however result in a much larger stem torque than does reinforced Teflon, requiring larger actuators.
Carbon-filled PTFE will probably perform acceptably long term, at 400 F and low pressure. Exceed 450 F though and the carbon-filled Teflon is likely to creep away on you.
There are some valve manufacturers who have been creeping up the well-established upper temperature limit of PTFE from 450 F (232 C) where it has been so for the entire previous generation, to 500 f (260 C), by claiming that their reinforcement/filler material makes that possible- metal powder, graphite, carbon fibre etc. Aside from vendor datasheets making this claim, I've seen no evidence from testing or service history that you can extend that limit to 500 F continuous duty in valve seats and seals with any of these fillers and still expect satisfactory long-term performance. I've asked for that evidence here and received crickets in response, so if anybody has it they've been silent about it.
Where you may be able to get away with this is in services where the service temperature is no more than 450 F but you need a "design" temperature of 500 F to handle brief upsets- then, perhaps, you'd be OK.
(Industrial)
19 Feb 15 15:52Our steam is about 400°F, and a few years ago we switched to PEEK-seated ball valves for vents and drains. Been working well; one caveat - PEEK seats really increase the required actuating force on a ball valve. Check the force required to open or close the valves before you standardize on anything.
Also agree with moltenmetal, the 'new' uprated valve seating material is not backed with testing or history. If your valves will be hard to maintain or replace, go with PEEK and a longer handle.
(Mechanical)
(OP)
20 Feb 15 01:50Thank you all. We are moving forward with the PEEK seats
Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.
Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.
Click Here to join Eng-Tips and talk with other members! Already a Member? Login
Contact us to discuss your requirements of surface safety valves for sale. Our experienced sales team can help you identify the options that best suit your needs.