This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "Hot tapping" – news · newspapers · books · scholar · JSTOR(November 2008) (Learn how and when to remove this message)
Hot tapping,[1][2] or pressure tapping, is the method of making a connection to existing piping or pressure vessels without the interrupting or emptying of that section of pipe or vessel. This means that a pipe or tank can continue to be in operation whilst maintenance or modifications are being done to it. The process is also used to drain off pressurized casing fluids and add test points or various sensors such as temperature and pressure. Hot taps can range from a ½ inch hole designed for something as simple as quality control testing, up to a 48-inch tap for the installation of a variety of ports, valves, t-sections or other pipes.
Hot Tap Procedures:
A. A hot tap saddle, service saddle or welded threadolet, valve installed, assembly is pressure tested and hot tap machine attached.
B. Valve opened, hot tap completed, coupon or cut portion retained by latches on pilot drill. Pressure is contained within the hot tapping machine.
C. Cutter and coupon retracted and valve closed. Fluid is drained and hot tapping machine is removed. The tapped valve is now ready for the contractor's tie-in or IFT's linestop/stopple equipment to be inserted.[3]
Hot tapping is also the first procedure in line stopping, where a hole saw is used to make an opening in the pipe, so a line plugging head can be inserted.
Situations in which welding operations are prohibited on equipment which contains:
Mixtures of gases or vapours within their flammable range or which may become flammable as a result of heat input in welding operations.
Substances which may undergo reaction or decomposition leading to a dangerous increase in pressure, explosion or attack on metal. In this context, attention is drawn to the possibility that under certain combinations of concentration, temperature and pressure, acetylene, ethylene and other unsaturated hydrocarbons may decompose explosively, initiated by a welding hot spot.
Oxygen-enriched atmospheres in the presence of hydrocarbons which may be present either in the atmosphere or deposited on the inside surface of the equipment or pipe.
Compressed air in the presence of hydrocarbons which may be present either in the air or deposited on the inside surfaces of the equipment or pipe.
Gaseous mixtures in which the partial pressure of hydrogen exceeds 700 kPa gauge, except where evidence from tests has demonstrated that hot-tapping can be done safely.
Based on the above, welding on equipment or pipe which contains hazardous substances or conditions as listed below (even in small quantities) shall not be performed unless positive evidence has been obtained that welding/hot tapping can be applied safely.
Substances
Acetylene
Acetonitrile
Butadiene
Caustic soda*
Chlorine
Compressed air at a pressure in excess of 3000 kPa gauge;
Ethylene
Ethylene oxide
Fat/lean DEA/MEA;
High pressure steam (pressure in excess of 5000 kPa (ga))
Hydraulic Oil
Hydrogen (partial pressure in excess of 700 kPa (ga))
Hydrogen sulphide*
Hydrofluoric acid
Oxygen
Propene
Propene oxide
Sulphuric acid
Toxic substances.*
Constraints based on general hazard in the event of line puncturing during welding, not the welding process. Conditions:
Vacuum conditions;
Dissolved hydrogen in the pipe wall (e.g. due to service history);
Pyrophoric scale deposits.
Note: The above list is not exhaustive, but gives an indication only.
^"Hot Tapping". International Flow Technologies, Inc.
Hottapping, or pressure tapping, is the method of making a connection to existing piping or pressure vessels without the interrupting or emptying of that...
theft trade in Nigeria. These key players use methods such as hot-tapping and cold-tapping to perform oil bunkering and steal thousands of barrels of oil...
Tap water (also known as running water, piped water or municipal water) is water supplied through a tap, a water dispenser valve. In many countries, tap...
The hot chocolate effect is a phenomenon of wave mechanics in which the pitch heard from tapping a cup of hot liquid rises after the addition of a soluble...
permanent alterations or valve replacements/additions have been made. With a hottap previously made on a line, a line stopper is attached to a temporary valve...
space, so as not to affect the ship's balance, a technique known as "hot-tapping". Removal and clean-up plan The operation (from June 2013 onwards) was...
provides the intro on "Tap In". Produced and co-written by Dr. Luke, it marked Saweetie's second song to chart on the US Billboard Hot 100. The song was also...
Tap 2" in the search box). Louisiana Economic Development. Retrieved May 10, 2024. Fleming Jr, Mike (May 12, 2022). "Cannes Hot Package: Spinal Tap II...
also features a tap dancer, Jamie Pressnall, tapping as percussion. During the 1930s and the 1940s, Americans were able to watch tap dancers perform on...
Tapping the Source is a surf noir novel by Kem Nunn published in 1984. It is Nunn's debut novel and tells the story of a young man searching for his missing...
instant hot water dispenser or boiling water tap is an appliance that dispenses water at about 94 °C (201 °F) (near-boiling). There are hot-only and hot and...
used for tea, hot chocolate or other uses. The water in the alternate hottap is generally heated with a heating element and stored in a hot tank (much like...
of tapping. For a 90-tonne, medium-power furnace, the whole process will usually take about 60–70 minutes from the tapping of one heat to the tapping of...
temperatures, which means that a separate machine is needed for producing, e.g., hottap water. The COP of absorption chillers can be improved by adding a second...
covering "Ex's & Oh's" in 2016. Featured in Dance Spirit Magazine's “20 HotTappers Under 20” in 2009, Reich is widely recognized in professional dance circles...
a hole in the hull and pumping the fuel out. The process, known as "hottapping", was expected to take up to a week. A boom was placed around the ship...
— Spinal Tap Are Making a 'This Is Spinal Tap' Sequel". Rolling Stone. Retrieved May 12, 2022. Fleming, Mike Jr. (May 12, 2022). "Cannes Hot Package:...
registered organisations UWG Group successfully completes Shell Baram hottapping project, archived from the original on 30 January 2013, retrieved 7 October...
temporarily. The same effect can often be produced by running the comb under hottap water. "Chemical Resistance Chart for Ebonite and various other Materials"...
subsystems are: potable cold and hottap water supply plumbing drainage venting sewage systems and septic systems with or without hot water heat recycling and...
A hot spring, hydrothermal spring, or geothermal spring is a spring produced by the emergence of geothermally heated groundwater onto the surface of the...
contentious first 2020 presidential election debate, Tapper garnered attention for his response. He called it a "hot mess inside a dumpster fire inside a train...
chart, number 39 on the UK Singles Chart and number 55 on the Billboard Hot 100. It was certified platinum by Recorded Music NZ in 1993 for selling 10...
pig iron and slag has been tapped, the taphole is again plugged with refractory clay. The tuyeres are used to implement a hot blast, which is used to increase...