Instrument Tubing - Technical Data
Jump to the Various Sections of this and other Instrument Fittings and Tubing Pages: Instrument Tubing Selection | Instrument Tubing Preparation | Instrument Tubing for Hazardous Gas Service | Instrument Tube Bending | Minimum Straight Lengths | Fitting Preparations | Tubing Installation | Supporting Tubing | Instrument Tubing Welding | Plastic Instrument Tubing | Instrument Tubing Data Charts | Training | Instrument Tubing Links | Instrument Tubing and Fittings Manual | Technical Information on Instrument Tubing and Fittings | Codes and Standards | Compression Fittings | Excess Flow Valves | Instrument Fittings Technical Data | Instrument Manifolds, Monoflanges, Valves and Accessories | Prochem Pipeline Products | Other Links |
Instrument Tubing Selection
There is a huge selection of materials to choose from when selecting instrument tubing. The selection is dependent on the service, installation and how long the tubing is required. It is important that these are considered before making a choice. One has to be careful when selecting polished tubing as the manufacturers polishing can work harden it and increase the surface hardness to unacceptable levels. Thus when specifying tubing it is best to select dull annealed type, then one can be assured that no untoward hardening has occurred.
Instrument Tubing Preparation
The tubing surface is essential to sealing when using a compression fitting, hence good handling practices should be used to reduce scratches and protect surface finish. For example dragging tubing across any surface that could scratch its surface can cause real corrosion and sealing problems. On offshore facilities, scratches may lead to corrosion of 316SS tubing from salt water pitting.
Visual Inspection of Tubing
It is a good idea to visually inspect instrument tubing to ensure it is free from scratches and other damage. Severe scratches or damage to tubing could affect the safe installation of the compression fitting. It is recommended that tubing in poor condition should be disposed of. Finished tubes should be scratch free, reasonably straight and have smooth ends free of burrs.
When cutting tubing do not use a hacksaw, the correct tool is a tube cutter which has a sharp blade.
Using the correct deburring tool (usually found on the cutter), deburr both the inside and outside edges of tube ends.
It is recommended that instrument tubing is cleaned with dry instrument air, however where the service requires a high level of cleanliness a proprietary cleaning agent should be used.
Instrument Tubing for Hazardous Gas Service
On hazardous gas service take care to ensure that the correct wall thickness has been chosen. Gas molecules are small and can migrate through thinner wall tubing. Contact your tubing supplier for details.
Instrument Tube Bending
On applications where bending is required, a tube bender must be used. Follow the tube bender manufacturer’s instructions to assure good bends. Either compression or draw type hand benders should be used for tubing up to 1/2 inches. Above this size hydraulic tools are recommended.
Instrument Tubing Bending & Installation - Wesley Tucker - Instruments around a plant monitor and control systems ranging from pressure differentials to contents of materials measured in percentages. Installing tubing to and from various instrument locations involves an understanding of the process and the application. Tubing installation is often dictated by the requirements of process. Bending, positioning and bracing tubing means more than just measuring a straight line and getting enough tube to fit. Tubing benders permit maximum tolerances for pressurized lines while reducing waste from cracked, misshapen or misaligned tubes of all sizes - from ehow.
Minimum Straight Lengths
To ensure proper insertion depth into compression fittings minimum straight lengths of tubing are needed. The following information may be used as a reference for the bending radius and for the minimum straight length before the bend for proper installation.
- If the tubing O.D. is 1/2 inches or less, provide at least 25mm straight length.
- If the tubing O.D. is greater than 1/2 inches provide at least 50mm straight length.
If the straight length is not possible, an elbow should be used.
Compression fittings are supplied assembled. The fitting, pipe thread and general appearance should be inspected visually before use. It is recommended that fittings are not disassembled. Always ensure that the tubing material is softer than the fitting.
- If practical, it is recommended that instrument process impulse lines are installed in the vertical plane. Horizontal impulse lines are generally run with a slope of not less than one in twelve between the process connection and the instrument. Slope should be down from the tapping points for liquids and up for gases.
- For reasons of accessibility offset and stagger tube unions wherever practicable.
- Tube fittings must not be used to support instruments, which should be independently mounted.
- It is recommended that any Weld splatter on stainless tubing be removed.
- It is a good idea to ensure all instrument impulse lines are as short as possible. For lengths up to approximately 1m tubing is self-supporting, however for longer lengths it is recommended that the tubing be supported at approximately 1m intervals.
- The number of joints in the impulse line should be kept to a minimum. Process and utility piping must not be used for supporting instrumentation piping or tubing.
- Tubing should be adequately supported and braced. It is suggested that support fixing distances not exceed the following:
1/4 inch OD
1/2 inch OD
3/4 inch ODtd>
1 inch OD
- It is recommended that three or more tubes run in parallel are supported in steel angle or channel, or on cable tray or ladder with appropriate insulation.
- To avoid the possibility of corrosion, it is recommended that stainless steel tube and/or fittings (316, duplex or otherwise) is NOT be in direct contact or located directly under Zinc coated or galvanised components.
- Electrically non-conductive tubing clamps are available. These isolate ubing from its supports.
Beware of Tubing Vibration!
It is suggested that impulse lines for instruments shall be arranged to avoid:
- Movement through thermal expansion.
- Mechanical damage from impact.
When tube vibration is a problem, due to the closeness of machinery, process pressure changes or other excitation, it is recommended:
- Tubing is clamped to the monoflange, process take-off or process line using a suitable clamp with the minimum span between the compression fitting and the clamp.
- A vibration loop (pigtail) is installed in the tube span between the process line and any independent structure used to support the tube. The orientation of the loop should be chosen with due regard to the probable relative motion between the connections.
- The vibration loop crossover has a minimum clearance of 2 x tube OD to prevent fretting of the tube.
Instrument Tubing Welding
There are several instrument tube welders on the market, they are excellent for hazardous gas applications. These units provide consistent high quality welds when operated correctly.
Plastic Instrument Tubing
Ensure that extremely soft plastic tubing is used with an insert. Never use metal ferrules on plastic tubing.
Instrument Tubing Data Charts
Stainless Steel Tube - Covering Seamless Stainless Steel Tube in Duplex, Monel, PVC sheathed copper tube and exotic metals. This technical article includes important subjects such as Ferrule hardness, 2.5% Minimum Molybdenum, Pickled & Passivated vs. Bright Annealed Tubing along with weights and working pressures.
Hoke Gyrolok® Tubing Data Charts - These charts are very useful and contain information on design, type of tubing, tubing preparation, calculating Yield, Burst, and Maximum Allowable Working Pressures, Maximum Allowable Stress Values for Material at Various Temperatures, Stainless Steel Calculation Factor Tables, Maximum Working/Burst Pressures and Tubing Tolerances.
Pipe and Tube - Lots of very useful information here including descriptions on seamless and welded, common pipe and tube terms, manufacturing methods, nominal working pressures, pipe dimensions and weights, tube weights and working pressures.
Useful Facts About Stainless Steel - This technical data sheet is full of useful facts and information about stainless steel.
Selection of Materials - This very useful table gives the composition of the various materials used such as 304SS and 316SS etc.
Steel Terms and Definition - A very useful table full of term and descriptions.
It is strongly recommended that any personnel associated with the installation of tube fittings and tubing attend vendor courses that are Internationally available. Tubing and fittings may look easy, however they are complex, precision items which require fully competent personnel to install them - we suggest that individuals and companies take ICEweb advice and attend a course.. Prochem are Instrument Tubing and Fittings experts and have excellent Training Courses.
Instrument Tubing Links
http://www.hoke.com/ - some great information here.
|Fittings and Small Bore Tubing Systems - Handbook
This superb 72 page document from the Norwegian Oil and Gas Association covers most engineering aspects of small bore tubing and fittings.
Supercritical Instrument Installations - The Tricky Process of Designing Impulse Lines for ASME B31.1 Compliance - Allan G. Gilson P.E. - When it comes to tubing, everyone knows that a grip-type tube fitting will meet or exceed the rating of the tubing itself. This makes instrument tubing installation easy-right? Simply ensure that the tubing is sized correctly, and everything will work. Piece of cake. The recent generation of coal plants in the United States (and around the world) has seen a major increase in the use of supercritical technologies due to inherent efficiency advantages over subcritical designs. However, no gain is without cost in some form. Greater efficiency requires considerably higher pressures and temperatures, resulting in significant new challenges for critical system instrument impulse line design and installation. In a supercritical plant, the pressures and temperatures for the main steam and feed water cycles routinely exceed that of conventionally fired drum-type boilers and combined cycle units. These elevated pressures and temperatures are particularly challenging for boiler manufacturers and engineers. Compliance with ASME B31.1 Power Piping requires much thicker piping and tubing walls, as well as stronger materials for valves and fittings - from FlowControl.
Video - Techniques for Effective Tubing - Note these training videos from Yellow Jacket are for Copper Tubing only and whilst concentrating on HVAC applications have some useful tips. They cover Cutting, Deburring, Flaring, Swaging, Bending etc. They are large downloads.
Technical Document on Instrumentation Tubing and their Connections - Nirbhay Gupta - Instrumentation tubing covers both Impulse tubes (sensing lines) as well as pneumatic tubes. Connections include tapping points, root valves and tube fittings. Usually one has to refer to a myriad of technical documents, codes and standards to search for a specific aspect of tubing design or construction. This technical note is an attempt to put all the information at one place. The efforts have been put to expose the readers to all the aspects of tubing and make them aware of all the developments in the world.
Instrument Tubing and Fittings Manual
It is important to understand that both of the above can affect the ferrule(s) ability to seal on the tubing. It is recommended to order tubing manufactured to the plus (+) side of the outside diameter tolerance. Wall thickness variations can affect pressure ratings and flow characteristics.
Instrument Tubing and Fittings Manual - This is an excellent resource from instrumentationtubing.blogspot.com.au. ICEweb always acknowledges Authors however it is a shame that the originator who has obviously put lots of time and effort into this blog is anonymous - anyway for whoever it was WELL DONE!
Section 1 - Instrumentation Tubing Introduction
Section 2 - Design of Tubing and Tubing Systems
Section 3 - Technical Requirements of 304 SS tubes-
Section 4 - Pneumatic Tubing
Section 5 - ASTM Tubing Specifications Outside Diameter
Section 6 - Embedded Penetrations
Section 7 - Methods of Connections of Instrumentation Tubes
Section 8 - Guidelines for Take-Off Connections for Sensing Lines
Section 9 - Guidelines for Root Valves
Section 10 - Installation of Instrumentation Tubing
Section 11 - Impulse Tube/Sensing Line Support
Section 12 - Impulse Tube Installation Through EPs
Section 13 - Tube Fittings
Section 14 - Threads Used For Tube Fittings
Section 15 - Welding Methods
Section 16 - Instrument Tubing References and Suggested Reading
Just click on the super ICEweb links below for more Technical Information on Instrument Tubing and Fittings.
Analytical, Instrumentation and Mechanical Heat Tracing and Tube Bundles - A Tubing Bundle consists of a small diameter tube or group of tubes packaged in an insulated, weatherproofed jacket. It may be steam or electric traced to provide freeze protection or temperature maintenance. Tubing Bundles are used in Instrument hook-up and impulse lines, Analyser sample transport, Insulated Tubing and Jacketed Tubing. This page provides many relevant free technical references to Analytical, Instrumentation and Mechanical Heat Tracing and Tube Bundles.
Codes and Standards - A useful list of Instrument Fitting and Tubing Codes and Standards.
Compression Fittings - This is "Essential" reading for any Instrument Engineer or Technician.
Excess Flow Valves - These devices are a real "Safety Boost" in that they limit flow in the event of a rupture.
Instrument Fittings Technical Data - This is a page which has a vast amount of Technical Engineering Information on Instrument Fittings and Tubing.
Instrument Manifolds, Monoflanges, Valves and Accessories - Information on what is a great addition to an Instrument Engineers Instrument take-off design engineering arsenal. Saving potential "failure points" means enhanced safety!
The following technical information on other products are from PROCHEM PIPELINE PRODUCTS
Instrumentation - Includes information on
- Anderson Greenwood
- ATKOMATIC Solenoid Valve
- BuTech Pressure Systems - System components are available in every imaginable alloy to handle pressures form vacuum to 150,000 PSI (10,000 bar) in tube and pipe sizes from 1/8" to 1" and temperatures from -423°F (-253°C) to over 1200°F (649°C). Suitable for extreme application of erosive or corrosive solids, liquids or gases.
- Circor Tech
- Circle Seal
- Classic Filters - These filters are suitable for a variety of gas and liquid applications and are used in a wide range of industries around the world. The disposable microfibre filter elements are extremely efficient as well as being low cost. There are a number of benefits with this type of element and they offer high flow rates with very low pressure drops.
- DOPAK® Sampling Systems - Due to the growing complexity of the industrial processes in general and more specific for processes in the (petro)chemical and pharmaceutical industries, the need for tests and analyses increases continuously. The need for representative samples plays a critical role in ensuring product verification. Yet sampling directly from the process often includes the risk of exposure to the operator, as well as contamination and pollution to the environment. The Manual Sample Systems method reduces such risks with its patented design and simple method of operation.
- GO Regulator®
- GYROLOK® Twin Ferrule Tube Fittings
- HOKE® Instrumentation Valves
- King Instrument Company - King Instrument Company offers a comprehensive line of variable area flow metres including acrylic, polysulfone, glass and metal tube metres. Optional alarms and 4-20 mA transmitter available on selected models. See more technical information on ICEweb's Flow page.
- Prochem NPT Ball Valves - Full Bore 2-piece threaded valves allowing straight-through flow. Virtually no head loss and a superior performer with mildly abrasive as well as corrosive fluids. Ideal for in-line control of process fluids.
- Stainless Steel Braided Hoses - Teflon® Lined
- Stainless Steel Tube
- Thread Tape & Thread Paste
- HOKE® Pipe Fittings
Hydraulic - Includes information on:
- Tube-Mac Piping Technologies
- Tube-Mac - PYPLOK System
- Tube-Mac Non-welded Flange Connections
- Seamless Steel Tubes
- PYPLOK Tooling
- Stainless Steel Ball Valves - Hydraulic
- Stainless Steel JIC Fittings JIC Fittings and Adaptors provide a straightforward, positive, mechanical seal. They have been used for many years for reliable sealing in commercial, industrial and military applications. They are proven to supply dependable, reusable connections under a wide range of operating conditions including extremes of vibration, temperature and shock.
Valves and Actuator - Includes information on:
- Prochem Actuated Valve Package - Specialising in Poyam, ATC, BSM, Pacson and Habonim - Prochem can deliver actuated valves in any combination to suit your valve, actuator and control system specification.
- AMPO Poyam Valves These are high-technology valves with best performance and low maintenance costs. Applications include Cryogenic Service, High Pressure, General Service, Metal Seated and Special Application.
- BSM Valving Solutions - Emergency Fast Track Valve Producers and Delivery Specialists, providing Ultra fast deliveries. Hard to obtain valves need specialist engineering. These valves are manufactured in a wide range of exotic materials to tight specifications.
- ATC Actuators - The heart of the ATC actuator design is the revolutionary torque conversion mechanism combined with the integrated actuator spring. The simple operating principle offers a combination of high efficiency and small displacement, thereby creating greater design flexibility and improved reliability. This design flexibility, combined with the innovative integration of all actuator parts, results in the most compact actuator available in the market. In virtually all applications, irrespective of hydraulic or pneumatic supply, the ATC actuator diameter is smaller than the Face-to-Face dimension of the valve.
- Pacson Valves - These are high integrity valves specifically designed for the Oil and Gas Industry.
- Anderson Greenwood Primary Isolation Valves - Anderson Greenwood Instrumentation Products provide the ultimate solutions for a compact range of forged body Primary Isolation Valves, featuring a choice of end connections, body styles and valve technology.
- Habonim Industrial Valves and Actuators - Habonim’s new series of ZERO-Stem-Leak valves, is based on the HermetiX™ technology. HermetiX™ is a patented stem seal designed to reduce stem leaks to a minimum and to provide maintenance-free service.
Manufacturing - Includes information on:
- Quality Management System
- Fully Traceable and Complying Threads
- Leaders in Thread Manufacture
- Exotic Alloys
- Engineered Solutions
- World Class Manufacturing
- Safety, Integrity and Reliability
- Special Service
- Standard Products - BSP Fittings
- Standard Products - NPT Fittings
- Standard Products - Other
Piping Products - Includes information on:
- Branch Fittings - Details on a range of Buttweld, Socketweld, Threaded and Flanged reinforced branch fittings from 8 (1/4") NB upwards.
- BSP Fittings - Prochem manufactures a complete range (from 6 (1/8") - 100 (4") NB) of BSP tapered, BSP parallel and BSP fastening and sealing threads for a variety of applications, in class 150 and 3000. All our BSP threaded fittings are checked with calibrated gauges during manufacture. Each batch is further confirmed as being in compliance with the international standard and before they are released into the market, all products undergo a final visual and dimensional inspection by thread profiling.
- Buttweld Fittings - Concentric and eccentric reducers, equal and reducing tees, 45° and 90° elbows, buttweld caps and stub ends, are all part of the comprehensive range of buttweld fittings carried by Prochem.
- Duplex Stainless Steels - Duplex Stainless Steels are unlike the 300 (Austenitic) and 400 (Ferritic) series of stainless steels in that they have a structure consisting of approximately equal amounts of both ferrite and austenite. Therefore, they are often referred to as ferritic-austenitic stainless steels. With a chromium content ranging from 18 to 28 percent, they have improved passivity compared to standardgrades. The nickel content ranges from 4.5 to 8 percent which is insufficient to promote a complete austeniticcrystal structure, hence the mixedferrite-austenite structure. Most gradescontain molybdenum in the range of 2.5 to 4 percent plus small amountsof nitrogen - enhancing both strength and pitting resistance.
- Flanges - A flange is designed to connect sections of pipe, or to join a pipe to an assembly such as a pressure vessel, valveor pump. Flanges are joined by bolting, and sealing is completed with the use of gaskets, and fixed to the piping system by welding or threading.
- Heat Exchanger, Condensor & Boiling Tubes - Useful technical datasheet.
- Hygienic and Tube - Prochem is well established as a supplier to the food industry. A comprehensive range of BSM, Tri-clover and buttweld fittings and valves are available throughout Australia, complete with welded and annealed polished tubes to suit.
- NPT Fittings - NPT fittings are designed for high-pressure (class 3000 - class 6000) applications, and have a distinctive profile for maximum strength. All NPT products are checked with calibrated gauges during the manufacturing process and each batch is further confirmed as being in compliance with the international thread standard. Before they are released into the market, each item is subject to a final visual and dimensional inspection by thread profiling. Materials used comply with ASTM A403 or A182.
- Pipe Nipples - Pipe nipples are available in ASTM A403 WP316/316L or 304/304L materials, from 6 (1/8?) NB upwards, threaded BSP or NPT, bevelled or plain ended. Prochem has the ability to manufacture pipe nipples up to 6000 mm (6 m) in length in sizes 6 NB to 80 NB.
- Saflok Self-Locking Quick Coupler Range - Prochem provides the safest quick couplers on the market from Saflok. Included the patented locking cam arm, the Saflok design has no peer among other quick couplings.
- Socketweld Fittings - Prochem manufactures and supplies an extensive range of the highest quality Socketweld fittings, all thoroughly inspected to ensure complete dimensional compatibility with the requirements of the ASME B16.11 manufacturing standards.
- Swage and Pipe Nipples - Prochem manufactures, stocks and supplies a range of plain, bevelled and threaded concentric and eccentric swage nipples, from 8 (1/4") NB through to 100 (4") NB, withother sizes available on request. All swage nipples are either manufactured from seamless pipe or bar material and have an available working pressure equivavlent to straight seamless pipe. These fittings are available in ASTM A403 WP316/316L or 304/304L materials with other materials available on request.
- Stainless Steel Shim - Grade 316 shim, annealed and with a hardness rating of HV200, is available in coiled 305 mm (12?) wide rolls, in various thicknesses and sold by the linear metre.
- Stainless Water Solutions Package - With increased height of buildings, pressures, and life time expectations, people are turning to Stainless Steel for their Water Solutions. These pipe and fittings bear the Water Mark logo ensuring compliance to the industry specifications. Coupled with roll grooving, Prochem has the complete package to offer your Water Solutions package. All designers, architects and builders should contact Prochem to see how we can save you money!!
- Swing and Spring Check Valves.
- Pyplok - Now you can have the benefits of a welded joint, but without the hazards of hot work, using the Tube-Mac PYPLOK® DM andDP40 Series. It’s not only a permanent system, it goes on cold. This means all of the risks and requirements associated “with hotwork” are avoided.
- Pyplok Video's
Assembly and Verification Process of PYPLOK fittings.
PYPLOK fittings installed in a BOP (Blowout preventer) installed in the Gulf of Mexico at a depth of 2.400 m.
PYPLOK fittings - Assembly Using a Hose Crimper - Pyplok fittings can be also crimped with a hose crimper, allowing companies the use of the fittings without having to buy a portable unit. The time and cost savings compared to welding, cutting ring or flaring are huge.
PYPLOK fittings for Water Mist Piping - PYPLOK fittings are the perfect choice for high pressure water mist piping systems. They are very fast to install, more economical than classical systems and totally reliable.
Welded Duplex Tube - Welded Duplex Tube to: ASTM SA789/A789 UNS S31803/S32205.
Other Instrument Tubing Links
Pick the Proper Hose - Patrick Werrlein, Swagelok Company - Making a correct choice requires an understanding of hose components - The right hose keeps your process performing safely and cost effectively. The wrong hose could undermine your operations, put personnel at risk and compromise your bottom-line, sometimes without you being aware of it - from Chemical Processing.
The following technical link is available via Swagelok.
An Installer’s Pocket Guide for Swagelok® Tube Fittings - This Guide is a must for anyone associated with the Installation of Swagelok fittings. It is a large download so be prepared to wait a while.