Tuesday, 2 July 2013
Ball Valves: importance of the Ball
Some are surprised over the price variation of the Ball Valve. Yes, Ball Valve can vary much dependent on several factors such as:
1) Body type – forged or cast. 3-piece design of forged steel body is generally more expensive.
2) Ball material. For carbon steel and stainless steel ball valves, the ball is usually stainless steel for reason of corrosion protection and long-term leakage prevention. Stainless steel 316 ball is indeed more expensive than stainless steel 304 ball.
3) Ball type. There are 3 types: solid forged steel ball, solid cast steel ball, and hollow welded steel ball. Solid forged steel ball is the most expensive whereas hollow welded steel ball is the cheapest.
4) Ball plating and coating. Ball could be plated with chrome or electroless nickel. Ball could be coated with Stellite, chrome carbide, tungsten carbide or Teflon. Non-plated, non-coated ball is the cheapest option.
5) Facility grade. What is the grade of factory and machinery used for making the balls and ball valves? Grade A factory has CNC spherical grinders and 5-axis CNC lathe equipped with rotating table to manufacture the balls. Valve seats are also machined using CNC lathe and CNC vertical machining centre. On the opposite end, Grade C factory uses manual machining method whereby accuracy and precision is not guaranteed.
6) Full-bore or Reduced-bore. Full-bore ball valve is always more expensive, larger and heavier than the reduced-bore ball valve.
Ball valve is the most important of all mechanical valves (ball valves, gate valves, globe valves, gate valves, check valves, butterfly valves, etc.). Ball valve is often used as a control valve in the pipeline. So, don’t be a cheapskate. Do buy Grade A ball valves. Yes, Grade A ball valves are much more expensive than Grade B ball valves, but ball valves are crucial and daily used. Ball valves need to be the best in quality, reliability and durability.
Forget the Grade C ball valves, unless you intend to be a Cheat, a hit-and-run businessman.
In this blog post, let us look at the Quality aspect of the Ball.
Solid forged steel ball is the best option. Steel is forged out of a solid, round steel bar. The solid forged steel ball is denser than the cast steel ball. Steel grains are close together in forged steel, and there is no porosity in forged steel. Even in high pressure ball valve (Class 900 and greater), the liquid medium could not penetrate into the forged steel ball.
Solid cast steel ball is an economical option. Cast steel ball may contain some extent of porosity, and is unsignificantly less dense than forged steel ball. In high pressure ball valve (Class 900 and greater), the liquid medium may penetrate into the tiny porosities of the cast steel ball. In the fully-close position, for high pressure ball valves, there may be chance of micro leakage due to these tiny porosities of the cast steel ball.
Hollow welded steel ball is the sinful option. These are used in Grade C ball valves, and sometimes employed in Grade B ball valves. Welded steel ball is made of curved steel plates which are welded together. Hence, the welded steel ball is hollow in side. Easy way to differentiate the welded steel ball from the solid steel ball is the light weight of the welded steel ball. Welded steel ball is not good because the liquid medium could enter into the hollow portion of the welded steel ball. This would cause minor leakage of the ball valve in the fully-close position.
Before machining and finishing, we could easily identify the solid forged steel ball, solid cast steel ball and hollow welded steel ball. However, after machining and finishing, all these 3 types of ball look visually similar.
Quality of the ball is also affected by the machining of the ball. The best machining method is the CNC spherical grinder. Second best option is CNC lathe fitted with rotating table, which would give a 5-axis machining capability. CNC machining would enable the accuracy and precision of every single ball. CNC spherical grinder is better than CNC lathe because the grinding will produce better smoothness and better roundness. Grade A balls are always machined using CNC spherical grinders or CNC lathe with rotating table.
Grade C ball are machined using manual lathe machine, which could not guarantee the consistency and precision; hence, slight dimensional variation among the balls; so some balls will be good, some balls may cause leakage.
Finishing of the ball should be mirror finish. All Grade A balls have this mirror-like finish, which is easily achieved using CNC spherical grinder.
On the opposite end, Grade C balls will be hand lapped, using lapping compound, after the manual machining is completed. Manual machining also produce uneven roundness. If the person doing the hand lapping is unskilled, the uneven roundness will be continued. Grade C balls, being unevenly round and not mirror finished, will have tendency toward minor leakage.
With these explanations, I hope buyers could understand the importance of quality of Balls in the Ball Valves. Quality of Ball affects significantly the price of the Ball Valve. Quality of the Ball also plays a major role to determine the quality, reliability and durability of the Ball Valve.
Author welcomes comments at valve4oem@gmail.com
Readers are also welcome to befriend the author at www.facebook.com/Michael.Valves
Subscribe to:
Post Comments (Atom)
Kavaata Valves is manufacturers and Exporters of Three way ( 3 way ) ball valves ball valves, U drills, Ball Valves, Ball valves for acids in Belgaum, India.
ReplyDeletefor more details:
http://www.kavaatavalves.com
Very useful and informative blog about ball valve & industrial ball valve....
ReplyDeletePvc Ball Valve
Ball Valves
Kavaata Valves is manufacturers and Exporters of Forge Ball Valve, Forged Ball Valves, Forged Steel Ball Valve in Belgaum, India.
ReplyDeletefor more details:
http://www.kavaatavalves.com/forged-steel-ball-valves.php
I suffered your web site its very superb.
ReplyDeletevery good data on product i got apprehend helpful data thanks for this.
http://www.krishika.com PVC Ball Valves Manufacturer
I am mistreatment a lot of similar product, i feel you for the careful data regarding this.
ReplyDeletePVC Ball Valves Manufacturer
I read your blog. Its really good. and having very good content. very helpful to all. thanks for sharing this.
ReplyDeletePVC Ball Valves Manufacturer
Ball Valve Manufacturer
Three Way and Double 3 way transfer ball valve are designed and manufactured as per ISO17292 standards by Kavaata Valves in India
ReplyDeletefor more details:
http://www.kavaatavalves.com/three-way-ball-valves.php
Kavaata Valves are High Quality Ball Valves manufactured Ball Valve Component who have business interests in Textiles. Kavaata Ball Valves, give exceptional results under demanding conditions. They are made out of guaranteed quality raw material, Metal Seated ball valves. Three Way Ball Valves,Ball valves for acids, High Temperature ball valves, Double three way transfer ball valves,Ball Valves India.
ReplyDeleteFor more details
http://www.kavaatavalves.com
This comment has been removed by the author.
ReplyDeleteThe ball valves comes in two distinctive varieties that includes standard port and full port. A standard port valve comes with the smaller size of ball and are mainly used to control the minimal flow of fluids. On the other hand, a full port valve has an oversize ball that allows unrestricted flow of fluids. I try some of here Ball Valves . . .
ReplyDeleteOur Products and solutions are best advertising at domestic industry and exported towards the international locations and regions which include U.S.A and Southeast Asia, immediately after Anix Establishedin 1988. We now have put in place income departments and soon after provider places in huge and middle metropolitan areas all through China. We're going to achievement in giving our perfect quanlity assure and finest immediately after product sales assistance for our Anix generation.Our corporation has long been accredited according to ISO9001 and appraised as top quality types by Machanical Engineering Valve Supervision Bureau & Provinvial Testing Center in succesive yeras. Anix Valves USA
ReplyDeleteI read this article. I think You put a lot of effort to create this article. I appreciate your work. Anix Valve
ReplyDeleteHi,
ReplyDeleteThanks for the great details about various types of valves, i really looking out for this kind of information.
We are leading manufacturers of Solenoid Valves, Check Valves, Expansion Bellows, etc.
Nowadays the industrial valves used widely in all kinds of fields are metal valves. although the metal valve has a history with husbands of years and its structure and material is improved all the time, this valve now can not satisfy the requirement of high abrasion-proofness and high corrosion-proofness owing to the restriction of the metal material's own property. The present industrial valves are short in usage life and also have a great negative effect on the stability of the system operation.
ReplyDeleteuseful information on topics that plenty are interested on for this wonderful post.Admiring the time and effort you put into your b!..
ReplyDeleteglobe valve manufacturers in usa
Your information is really interesting to all readers. Hope you continue to keep up with this blog and will provide us some more information like this.
ReplyDeleteStainless Steel Valves
Thank you so much Love your blog..
ReplyDeletewholesale fittings
i love reading this article so beautiful!!great job!
ReplyDeletevalves manufacturer
nice blog we are also a supplier of Pneumatic Ball Valve in Mumbai
ReplyDeleteI am happy to find this post Very useful for me, as it contains lot of information. I Always prefer to read The Quality and glad I found this thing in you post. Thanks Anix USA
ReplyDeleteThis comment has been removed by the author.
ReplyDeleteValve and fittings Store USA works with reliable manufacturers to offer products with excellent quality. ValveFittingStore
ReplyDeleteI'm very touched with your post...... Are you looking for Bathroom fitting Accoriess, then feel free to click on the links.....
ReplyDeleteBrass Radiator Valves
Full Bore Ball Valve
Brushed Brass Shower Set
Water Pre Filter
4 Inch Sewer Check Valve
Cooker Hood Suppliers
Nice blog....Visit us....
ReplyDelete4 Inch Sewer Check Valve
Brass Radiator Valves
Brushed Brass Shower Set
Full Bore Ball Valve
Installing Pex Plumbing
Thread Fitting
Water Pre Filter