,

How to replace a ball valve

Ball valves are an integral part of plumbing and piping systems. These valves are highly durable and leak-resistant by and large, but they are not immune to damage. Replacing a damaged ball valve is relatively simple if the correct sequence of steps is followed. This article discusses how to replace a ball valve connected to a copper pipe or PVC pipe in case the valve doesn’t work properly.

Ball valve issues

A ball valve is a shut-off valve that directs the flow of a fluid by means of a rotary ball having a hole. There are a few potential ball valve failures like getting stuck, fluid leakage, corrosion, and overheating, resulting in the valve not functioning properly. Typically, there are three cases:

  1. Ball valve issues that can be fixed manually: Issues like a stuck ball valve that prevents fluid flow, sediment and dirt buildup that makes the valves difficult to open and close, or actuator issues can be easily solved by manual intervention as discussed in our article on ball valve issues and troubleshooting.
  2. Ball valve issues that can be fixed by replacing a part: Issues like a partially closing ball valve, worn-out O-ring, and stem may require certain parts of the ball valve to be replaced with new ones rather than ordering a whole new valve.
  3. Ball valve issues that require a total replacement: Certain issues like a leaking ball valve may require the whole valve to be replaced with a new one.
A rusted ball valveFigure 2: A rusted ball valve

How to replace a ball valve

The following is an example on how to replace a ball valve on a water line with a new one. The same principles apply for other applications.

Step 1: Turn off the water

Turn off the main water supply to all the pipes being worked on. Then, drain the existing water pressure in these pipes by turning on the connected faucet.

Step 2: Access the pipes

Accessing the pipes is necessary to replace an existing ball valve. For example:

  • A sink: Try to access the ball valve underneath the sink.
  • Shower pipe/bathtub faucet: Either via the basement crawlspace or via breaking the wall that has the pipe attached.

This step helps plan in advance whether to break the wall for replacing the required valve.

Three-dimensional representation of copper and PVC pipes within a wallFigure 3: Three-dimensional representation of copper and PVC pipes within a wall

Step 3: Cut the old valve out

Once there is full access to the pipes, use a hacksaw to cut off the old ball valve residing in the pipe (marked in red circles in Figure 4). For this, cut the two sides of the pipe where the valve is placed, and get the valve removed from its position. In case the old valve can be unscrewed from its position, remove the valve and skip to Step 8.

A ball valve connected in a pipe system. The red circles show the points where the pipe needs to be cut to remove the valve.Figure 4: A ball valve connected in a pipe system. The red circles show the points where the pipe needs to be cut to remove the valve.

Step 4: Disassemble the ball valve

Disassemble the ball valve parts and make sure to keep all the parts together. This ensures that if any of the individual parts are salvageable, the reassembling process can be done with ease.

Step 5: Inspect the ball valve parts

Inspect the ball valve parts for any cracks or wear and tear that might have led to the leaking or nonfunctional ball valve. If a specific part of the valve seems faulty while the rest of them seem normal and function well, the best option would be to order a replacement part. Read our ball valve leakage troubleshooting article for more details on the causes of ball valve leakage and how to troubleshoot them. After getting the damaged part replaced, use lubricating oil and screws to reassemble the ball valve parts. If there is damage to multiple parts of the valve, or if the ball valve seems damaged beyond repair, it is a better option to get a completely new ball valve.

Step 6: Buy a new valve/valve part and other supplies required

Have an idea about the type of pipes installed so that it is easy to buy a new pipe section and seals required.

  • Copper pipe: A plumber’s tape or sweat pipe joints
  • PVC pipe: Pipe cement

Also, get a spackle and a new valve or valve part(s) based on the needs.

Step 7: Splice the pipe

Splice the new pipe section onto the pipe where the valve was cut. Allow enough space for the new ball valve to fit in.

  • PVC pipe: Apply PVC glue to the existing pipe where the cut was made and on one end of the new pipe. Push the new pipe onto the existing pipe and hold for approximately 30 seconds. Connect a coupler to one end of the new pipe if needed.
  • Copper pipe: Two copper pipes can be connected together by soldering their ends or by using a coupler. Read our article on ball valve soldering for the detailed soldering process employed in the plumbing industry.

  • Step 8: Install the new/repaired ball valve

    Install the new/repaired ball valve properly into the pipe.

    • Copper pipes typically need to be soldered to the valve. Read our article on ball valve soldering for detailed instructions on how to solder a ball valve to a copper pipe.
    • For installing a ball valve to a PVC pipe, cover one end of the pipe using pipe dope and insert the ball valve into the pipe. Then brush pipe dope to the other connecting end of the pipe and insert the other port of the valve.
    • Welded connections are used for ball valves where zero leakage is crucial for high-pressure and high-temperature applications. Welded connections are permanent and should be carried out only by trained professionals.
    • Threaded connections are useful to install small valves to pipes. Typically, the valve has female threaded ends that connect to a male threaded component. In some cases, the valve has male threaded ends or one male threaded end and the other a female threaded end. Threaded connections can either be straight or tapered. Straight connections often require an O-ring that compresses to ensure a tight seal between the valve and the pipe. The tapered thread does not require an O-ring to achieve a tight seal. Both types of thread can use pipe tape or a sealant between the male and female thread, which serves as a lubricant, provides sealing, and prevents metal-to-metal contacts that cause wear.
    • Ball valves with flanged connections are quite easy to install and can be easily removed for cleaning and maintenance without affecting other parts of the pipe network. They are very common in industrial applications. The flanges are solid metal plates with holes through which bolts and nuts are placed to tighten the valve to the pipe.

    Step 9: Test the ball valve installation

    Turn on the water supply and faucets that were previously turned off for the installation. Check for leaks in the pipes. If there are no leaks, the broken walls that contain the pipes can be closed. If the pipes leak, go back into the steps and make the proper connections required.

    If the wall had to be cut into, place the part back and paint over it with spackle. If the valve was below the sink, just close the cabinets.

    FAQs

    Can you replace a gate valve with a ball valve?

    Yes, a ball valve is superior in terms of performance compared to a gate valve; hence, it is a good idea to replace a gate valve with a ball valve if needed.

    Can ball valves fail?

    Yes, a ball valve can fail due to a damaged seal (the valve won’t close fully) or foreign particles entering the valve (the valve gets stuck).

    What is the life expectancy of a ball valve?

    The average life expectancy of a ball valve is 8-10 years. Ball valves get worn out due to continuous rotation.

/by
,

ISO 5211 For Industrial Valves

ISO 5211 is an international standard that specifies the flange dimensions, driving component dimensions, and torque reference values for part-turn actuators that connect to industrial valves like butterfly and ball valves. The standard also defines the different types of drive inserts used for these actuators. This article concentrates primarily on ISO 5211 standard and the other relevant ISO standards used for ball valves and butterfly valves.

ISO 5211 standard

Modern valve designs are compliant with an ISO mounting interface. The actuator can be mounted directly to the valve without a bracket and drive log, thus saving time, hassle, and money. The highlight of following a standard like ISO 5211 is that the user can buy the parts from any manufacturer and then mix and match the valve and actuator and replace a single part if needed.

ISO 5211 is an international standard that specifies requirements for the attachment of part-turn actuators (with or without gearboxes) to industrial valves. ISO 5211 specifies the following parameters:

  1. The flange dimensions necessary for attaching part-turn actuators to industrial valves or intermediate supports.
  2. The driving component dimensions of part-turn actuators necessary to attach them to the driven components.
  3. The reference values of torques for interfaces and couplings.

Flange dimensions

Flanges for part-turn actuators (Figure 2 labeled 1) comply with the dimensions shown in Figure 2 and Table 1. The flanges can be attached by screws, studs, or bolts. Holes for the studs, screws, or bolts are equally spaced apart and positioned off-center (see Figure 3 and Table 3), and conform to the requirements of ISO 273. ISO 273 specifies the clearance hole diameters for general purpose applications. These values are from bearing area calculations connected to ISO bolt and nut product standards.

Flange dimensions of a part-turn actuatorFigure 2: Flange dimensions of a part-turn actuator

Table 1: Flange dimensions (in mm)

Flange type d1 d2 d3 d4 h1max h2min No. of bolts/studs
F03 46 25 36 M5 3 8 4
F04 54 30 42 M5 3 8 4
F05 65 35 50 M6 3 9 4
F07 90 55 70 M8 3 12 4
F10 125 70 102 M10 3 15 4
F12 150 85 125 M12 3 18 4
F14 175 100 140 M16 4 24 4
F16 210 130 165 M20 5 30 4
F25 300 200 254 M16 5 24 8
F30 350 230 298 M20 5 30 8
F35 415 260 356 M30 5 45 8
F40 475 300 406 M36 8 54 8
F48 560 370 483 M36 8 54 12
F60 686 470 603 M36 8 54 20
Positions of holesFigure 3: Positions of holes

Table 2: Position of holes

Flange type ⍺/2
F03 to F16 45°
F25 to F40 22.5°
F48 15°
F60 9°

Drive inserts

Drive inserts allow the actuators to directly mount to the valve in accordance with ISO 5211. Direct mounting eliminates the need for a coupling-type mounting kit and significantly cuts the valve/actuator assembly cost. ISO 5211 covers parallel and diagonal square drives, flat head drives, and single and two key drives. These drive inserts are on factory-built actuators or come as separate units. Also, these inserts are easily replaceable at the distributor or end-user level.

Drive inserts for connecting ISO 5211 actuator to butterfly valves: Actuator (A), drive insert (B), Butterfly valve (C)Figure 4: Drive inserts for connecting ISO 5211 actuator to butterfly valves: actuator (A), drive insert (B), butterfly valve (C)

ISO 5211 torque chart

As per the ISO 5211 standard, the maximum torque transmitted through the mounting flange of a butterfly or ball valve should comply with the values listed in Table 3. The values specified in Table 3 are based on bolts in tension at a stress of 290 MPa and a coefficient of friction between the mounting interface of 0.2. Any variation in these defined parameters can lead to variations in the values of torque transmitted. Hence, while selecting a flange type for a particular application, the additional torque that inertia or other factors may generate should be considered.

Table 3: Maximum flange torque values as per ISO 5211 standard

Flange type Maximum flange torque (in Nm)
F03 32
F04 63
F05 125
F07 250
F10 500
F12 1000
F14 2000
F16 4000
F25 8000
F30 16000
F35 32000
F40 63000
F48 125000
F60 250000
F80 500000
F100 1000000

Designation

Part-turn valve actuators that comply with ISO 5211 standard can be designated as shown in Table 4.

Table 4: ISO 5211 valve designation

Flange designation Spigot identification Drive identification Drive dimensions (in mm)
Flange types given in Table 1 Y: with spigot 

N: without spigot

 V: Single key drive 

W: Two key drive

L: Parallel square drive

D: Diagonal square drive

H: Flat head drive

 The actual dimensions of the drive in mm

Example

Consider a part-turn actuator with the following designation:

EN 150 5211 – F07 – Y – V – 22

The designation can be decoded as follows:

  • F07: Flange type
  • Y: With spigot
  • V: Single key drive
  • 22: 22 mm drive diameter

Therefore, EN 150 5211 – F07 – Y – V – 22 identifies a part-turn actuator attachment in accordance with ISO 5211 standard with F07 flange type, spigot and single key drive with a 22 mm diameter. Please note that marking the designation on the actuator is not mandatory. Refer to the ISO 5211 document for more information on the dimensions of drive components for different types of drive inserts.

Additional features of ISO 5211 actuators

ISO 5211 direct-mounted valves come with additional features like a blow-out proof stem design, handles with an inherent locking device, or an anti-static design. In a ball valve, an anti-static design eliminates the static charge generated on the ball due to friction. The design protects the valve against sparks that can ignite the fuel flowing through the valve. ISO 5211 actuator options for modulation DPS (Digital Positioning System) or fail-safe BSR (Battery Safety Return) are also available.

Other ISO standards for butterfly valves

ISO 5752

ISO 5752 standard for butterfly valves specifies the basic series of face-to-face and center-to-face dimensions for two-way metal butterfly valves. Each basic series applies to flanges of mating dimensions conforming to the equivalent EN or ASME flange series.

The face-to-face dimension is the distance between the two gasket contact surfaces. (Figure 5 left side). The center-to-face dimension is the distance between the plane at the extremity of either body end port and perpendicular to its axis and the other body end port axis (Figure 5 right side).

Face-to-face dimension of butterfly valve denoted by ‘a’ and center-to-face dimension denoted by ‘b.’Figure 5: Face-to-face dimension of butterfly valve denoted by ‘a’ and center-to-face dimension denoted by ‘b.’

ISO 10631

ISO 10631 specifies the general requirements for design, materials (e.g., steel, cast iron, ductile iron, copper alloy), pressure/temperature ratings, and testing for butterfly valves having metallic bodies for use in flanged or butt-welding piping systems.

IS0 16136

ISO 16136 specifies the requirements for the design, functional characteristics, and manufacture of butterfly valves made of thermoplastic materials intended for isolating and control service, their connection to the pipe system, the body materials, and their pressure/temperature rating between − 40 °C and + 120 °C, for a lifetime of 25 years, and also specifies their tests after manufacturing.

Other ISO standards for ball valves

ISO 7121

ISO 7121 specifies the requirements for a series of steel ball valves suitable for general-purpose industrial applications. The standard covers ball valves of nominal sizes and is applicable to Class 50, 300, 600, 800, and 900 pressure designations. It includes provisions for ball valve characteristics as follows:

  • flanged and butt-welded ends in sizes 15 ≤ DN ≤ 600 (1/2 ≤ NPS ≤ 24)
  • socket welding ends in sizes 8 ≤ DN ≤ 100 (1/4 ≤ NPS ≤ 4)
  • threaded ends in sizes 8 ≤ DN ≤ 50 (1/4 ≤ NPS ≤ 2)
  • body seat openings designated as full bore, reduced bore, and double reduced bore
  • materials
  • testing and inspection.

ISO 17292

ISO 17292 specifies the requirements for a series of metal ball valves suitable for petroleum, petrochemical, natural gas plants, and related industrial applications. It includes provisions for testing and inspection and for valve characteristics as follows:

  • flanged and butt-welded ends, in sizes 15 ≤ DN ≤ 600 (½ ≤ NPS ≤ 24)
  • socket welding and threaded ends, in sizes 8 ≤ DN ≤ 50 (¼ ≤ NPS ≤ 2)
  • body seat openings designated as a full bore, reduced bore, and double reduced bore
  • materials

ISO 23826

ISO 23826 specifies the design, type, testing, marking, manufacturing tests, and examination requirements for ball valves used as:

  • closures of refillable transportable gas cylinders, pressure drums and tubes
  • main valves for cylinder bundles
  • valves for cargo transport units [e.g. trailers, battery vehicles, multi-element gas containers (MEGCs)], which convey compressed gasses, liquefied gasses, and dissolved gasses.

However, the standard does not apply to ball valves for oxidizing gasses, toxic gasses, and acetylene for single gas cylinders, pressure drums, and tubes.

/by
,

The floating ball valve vs the trunnion mounted ball valve

‘’Floating ball’’ and ‘’trunnion ball’’ are concepts which are used generally. But what are the exact difference between these two designs and when to use which one?

The most important difference between these two design is the construction of the ball and the way in which it is assembled inside the valve body. A trunnion ball is attached and centred inside the valve body through both a top shaft -the valve stem- and a bottom shaft – the trunnion. A floating ball is attached to the valve body only through the valve stem. As a result, the floating ball ‘’floats’’ in the valve seats.

In a floating ball design the ball is pushed against the downstream seat by the in-line pressure, resulting in tightness. When operated from closed to open position, the ball is to be rotated against both the in-line pressure (∆p) and the friction of the seats. In other words: the torque needed to operate the valve is created by both in-line pressure and the nature of the valve seats. The amount of torque required increases significantly when operating pressure (∆p) and/or valve size increase, and/or whenever the nature of the seat is made more robust. The latter applies in case of a metal seated valve design.

Floating ball
Trunnion ball

In a trunnion design, the ball is inserted in a central bottom shaft which is called the trunnion. The ball is fixed between the stem and the trunnion, which inclines that the ball is not floating but fixed and centred. The inline pressure presses the seats against the ball, causing the tightness. This inclines that during operation, the ball does not have to be rotated against the in-line pressure (∆p) and the valve seats, but that is solely needs to be rotated against the pressure of the seats.

 

Floating ball & trunnion ball

As a result, the required torque of a trunnion mounted ball valve is generally lower than the torque required of a comparable floating ball valve. For example: a DN200 metal-seated floating ball valve would require a significantly larger actuator than a DN200 comparable trunnion valve, leading to significantly lower costs of the overall package. Also, in general the trunnion seat design offers higher stability which makes it more suitable for extreme conditions and especially varying pressure levels.

So, the trunnion-mounted ball valve is more suitable for high pressure applications and bigger dimensions compared to the floating ball. Another advantage of the trunnion design vis-à-vis the floating design is the fact that a trunnion generally is included with a drain or bleed connection, making it suitable to function as a dual safe device. Furthermore, it functions as an relief valve automatically whenever the pressure in the central cavity is higher than the spring force of the seats. When this happens, the seat springs relieve automatically in order to drain the excess pressure back into the main line. Because of these reasons, the trunnion is commonly used in offshore- & oil & gas applications, where extreme conditions pose the standard.

Off course, a large disadvantage of the trunnion compared to the floating design is associated with its costs; which are significantly bigger. Because of these costs, trunnions are used solely when they have to be used.

Our specialist happily assist you in advising the right ball valve design for your application.

/by