Showing posts with label steam trap. Show all posts
Showing posts with label steam trap. Show all posts

Wednesday, January 10, 2018

Steam Trap For Heavily Contaminated Steam

cast iron float steam trap
The Float Trap series is available in carbon or stainless steel.
Image courtesy Spirax Sarco
Industrial process gear and equipment manufacturers are always tweaking designs, adding features, and creating new product variants in response to the challenges presented by the immeasurably broad range of application and operation scenarios for their products. Spirax Sarco is a globally recognized leader in the design and manufacture of steam system specialties, and has created a rugged steam trap to accommodate some tough challenges.

The company's FTC23 and FTS23 Float Trap products are ball float steam traps suitable for use with saturated and superheated steam. The units can be utilized on process equipment and for drainage of temperature controlled systems. These traps are specifically targeted at applications involving steam that may be carrying solids or incondensable gasses. Solids, if not purged from the system, can accumulate and foul the internal trap mechanism, leading to failure.

The company indicates that the main design feature is a self-cleaning float closing mechanism which maintains safe operation even in the presence of severe contamination. The positioning of the valve and seat also promote the discharge of the condensate, along with entrained contaminants. There is even a manual lever on the exterior of the trap that allows an operator to force the full opening of the valve, regardless of whether condensate is present. This operation facilitates fast removal of contaminants and maintains optimum performance.

The two models differ in their construction materials, with one having a carbon steel body, the other a stainless steel body. Internals are stainless steel on both units.

Share your challenges with the steam system specialists, leveraging your own knowledge and experience with their product application expertise.

Thursday, December 21, 2017

Capsule Steam Traps

cutaway view capsule steam trap
Capsule type steam trap, cutaway view
Image courtesy Tunstall Corporation
Steam traps are an important part of a closed steam system, directing condensate on a path back to the boiler for reuse and venting non-condensing gases from the system. Of the several different types of steam traps utilized commercially, the thermostatic steam trap is but one. Thermostatic traps are often applied when the application can benefit from a utilization of some of the heat remaining in the condensate. This trap design will hold the condensate in place until it cools sufficiently below the saturation temperature of the steam.

Capsules utilized in thermostatic steam traps contain the controlling elements of the device. The parts are somewhat subject to wear through their movement, but more so from the corrosive effects of system fluid, impurities, and mechanical shock from water hammer. Tunstall Corporation specializes in the manufacture of replacement capsules for thermostatic steam traps that provide better service and extended warranty duration. Their sealed units are fabricated of stainless steel and welded to seal out deterioration due to exposure to steam and condensate. Drop in replacement capsules are available for conceivably every trap manufactured in the previous few decades.

Share your steam system requirements and challenges with application specialists, leveraging your own knowledge and experience with their product application expertise to develop an effective solution.

Friday, August 18, 2017

Thermodynamic Steam Traps

cutaway view thermodynamic steam trap
Cutaway view of disc type thermodynamic steam trap
Image courtesy of Spirax Sarco
Condensate return is an essential operation in any closed loop steam system. Steam that has lost its latent heat will collect in the piping system as hot liquid water (condensate). This liquid needs to be separated from the steam and returned to the boiler feedwater equipment without letting steam escape in the process.

Various items of steam utilization equipment and processes will result in condensate formation at different rates. The device that collects and discharges condensate to the return portion of the system is called a steam trap. There are numerous physical principals and technologies employed throughout the range of available steam trap types. Each has application limitations and strengths making them more or less suitable for a particular installation.

A thermodynamic steam trap relies on the energy provided by the condensate to move a disc which controls the flow of the condensate into the return system. The disc is the only moving part in the device. Condensate flows through a port to a chamber on the underside of the disc, lifting the disc and directing the flow to the return system or drain. Eventually, the fluid flowing into the chamber will reach a point where some of the condensate flashes to steam. A portion of this steam flows through a channel into the space above the disc, called the control chamber. The increase in pressure in the control chamber due to the steam influx pushes downward on the disc, seating it in a closed position. The trap, with the disc seated, remains in the closed position until the flash steam in the control chamber cools and condenses. Then the disc can be opened again by the inflow of condensate.

The thermodynamic disc trap is:

  • Easy to install
  • Compact
  • Resistant to damage from freezing
The single trap can cover a wide range of system pressure, and the simple construction translates into low initial cost. Properly matching any steam trap to its application is important. Share your condensate return and steam system challenges with specialists, combining your knowledge and experience with their product application expertise to develop effective solutions.

Tuesday, May 2, 2017

Steam Traps

high pressure float type steam trap cutaway view
Cutaway view of high pressure float type steam trap
Courtesy Spirax Sarco
Steam is widely used throughout industrial, commercial, and institutional facilities and a means of transferring heat energy, as well as a wide array of other applications. Steam generation cost is a substantial line item on almost any balance sheet, so deriving the most efficient level of operation from a steam system pays tangible dividends.

Utilizing the heat content of steam, in a closed system, results in the production of condensate. Condensate is hot liquid water which can be returned to the boiler and re-vaporized. Managing the separation of the liquid condensate from the process steam and sending it to the lower pressure condensate return line is the function of a steam trap. A steam trap filters out condensate (condensed steam) via an automatic valve. The trap also removes air without letting process steam escape. By filtering out the condensate and not the steam, steam waste is minimized. Steam traps generally are self-contained automatic devices. Since steam based heating processes generally rely on latent heat transfer for rapid and efficient operation, it is necessary to continually collect and transfer condensate from the steam containing portion of the system. The condensate will reduce heat exchanger performance if allowed to accumulate.

Historically, there have been three main types of steam traps: mechanical traps, thermostatic traps, and thermodynamic traps. Most commonly used mechanisms rely on differences in temperature, specific gravity, and pressure. The mechanical trap was originally developed as a bucket trap, which was a rather large trap where a bucket floated up or down to open and close a valve. Bucket traps with a lever, which face downward – also known as ‘closed bucket’ traps – are still used today as a float type trap. Processes requiring large capacities for discharge still currently use the bucket type or float type trap, with long services lives. In the modern version of a free float trap, the condensate is continuously discharged while the valve opening is constantly controlled by the amount of buoyant force acting upon a tightly sealed float.

Thermostatic traps are a smaller, more compact design. Using a temperature sensing mechanism, and operable by mechanisms like bellows or bimetal rings, these thermostatic traps have a slower response. Processes relying on rapid condensate discharge most likely will not use thermostatic traps. An example of a trap used in the process industry today is a bimetal temperature control trap. The trap includes steam tracers and will discharge when a certain condensate temperature is reached.

The core limitation of thermostatic steam traps – the slow response time – has been addressed via the development of the thermodynamic steam trap. The thermodynamic trap operates on the expansion and contraction of an encapsulated liquid. This version of steam trap allows for the smallest amount of condensate accumulation. Early models resulted in unacceptable levels of steam loss. As a result, the commonly used disc type trap was developed for mainstream use. The disc type is compact, versatile, and relatively affordable in terms of installation costs. In the modern disc type, pressure fluctuations in the chamber above the valve result in the valve’s opening and closing. Though in use for many years, development and refinement continues on steam traps, bringing ever better performance to this ubiquitous steam specialty.

Share your challenges with a steam system specialist, combining your own process and facilities knowledge and experience with their product application expertise to develop effective solutions.

Monday, January 2, 2017

Steam Trap Maintenance Made Easier With Pipeline Connector

steam trap isolation valve set
PC4000 Pipeline Connector
Courtesy Spirax Sarco
Steam is a common source of heat or power throughout industrial and commercial installations. Most steam systems operate as a closed system, with return of condensate to maximize energy efficiency and gain other operational benefits. Steam traps are the workhorse of many condensate return systems, routing condensate back to the boiler and non-condensible gases out of the system, all without a major loss of steam.

Steam traps are points of high maintenance in the steam system. They are also an integral part of the system, meaning they are under pressure. Steam trap maintenance requires isolating the trap from the system, venting the pressure within the isolated section, and removing liquid that may be contained in the trap.

Spirax Sarco, globally recognized leader in steam system componentry and controls, provides a single unit solution for steam trap maintenance isolation. The PC4000 pipeline connector series (in the company's own words)...
"...are a complete 'Trap valve station solution' developed for use with two bolt universal swivel connector steam traps.
As the unit has been designed with two integral piston stop valves, it is possible to isolate both upstream and downstream of the universal trap connection and through the use of the fitted depressurization valves, possible to depressurize, test and drain the pipeline. The trap depressurization port also incorporates a maintainable 40 mesh stainless steel strainer screen to provide trap protection from system dirt and debris, which can be cleared through the use of the line pressure."
 A detailed data sheet is provided below for further review. Share your steam system challenges of all types with specialists, combining your facility and process knowledge with their product application expertise to develop effective solutions.

Tuesday, November 1, 2016

New High Pressure Float Type Steam Trap

steam trap high pressure float type
Model FTC62 High Pressure Steam Trap
Courtesy Spriax Sarco
Steam is utilized by industrial operations as a source of heat and power. Commercial and institutional facilities widely employ steam as a heating source. The overall cost of operating a steam system is generally significant, regardless of the size of the organization. Designing a system to deliver efficient performance and maintaining that performance throughout many years of expected operation requires continuous monitoring and attention.

One facet of efficient operation is to remove condensate from the steam system and return it to the boiler. This operation is the primary function of a steam trap. Additionally, a steam trap will also remove non-condensible vapor from the system. Liquid water and non-condensible vapor both will undermine efficiency in a common steam system.

There are many versions of steam traps available, and it is important to match the capacity and performance range of the trap to the steam system. Spirax-Sarco, globally recognized steam system specialties manufacturer, has added  a new steam trap model series to their already extensive offering.

The FT62 Series, which is available with a carbon steel (FTC62) or stainless steel (FTS62) body, has stainless steel internal components. It is intended for application on light and heavy condensate loads on steam systems with differential pressure up to 900 psig (62 bar).  The unit includes an integral air vent and an easily maintainable in-line strainer.

More information is provided below, with good illustration of the exterior and interior setup of the steam trap. Share your steam system requirements and challenges with experienced application specialists, combining your facility and process knowledge with their product application expertise to develop effective solutions.

Tuesday, May 24, 2016

Understanding Condensate Pumps on a Steam Distribution System

industrial steam system
Diagram of industrial steam system
(courtesy of Watson McDaniel)
condensate pump is a specialized device intended for use in transferring condensate (water) produced in an industrial steam system. Condensate from a heating system or process is collected, then pumped to the condensate return system, where it is routed back to the boiler for reuse.

In certain cases, the steam pressure of the system may be sufficient to push the condensate through the steam traps and condensate return lines, back to the condensate holding tank in the boiler room. In most practical situations, however, one or more condensate return pumps are required to assist in overcoming gravity, pressure drops from long piping runs, and back pressure in return lines.

Condensate Return Pumps are either electrically-driven centrifugal pumps or non-electric mechanical pumps that use steam pressure as the motive force to pump the condensate. Non-electric pumps are referred to as Pressure Motive Pumps (PMPs).

A facility will often have a separate area that contains various components required for the generation of steam, such as a boiler, condensate holding or deaerator (DA) tank, boiler feed pump, water treatment, etc. Regulated by the boiler control system, the boiler feed pump sends condensate from the holding tank back to the boiler.

Pressure Motive Pumps (PMPs) are non-electric pumps which return condensate back to the boiler room; using steam pressure as the motive force. PMPs can be supplied as stand-alone units – which include a pump tank, the internal operating mechanism, and a set of inlet and outlet check valves, or: as a packaged system – which also includes the vented receiver tank (to collect the condensate) mounted on a common base.

The following is a comprehensive document, courtesy of Watson McDaniel, that provides a good general understanding of steam and condensate systems, traps and condensate pumps. 

Friday, October 31, 2014

The Operation of Bimetallic Steam Traps

Bimetallic steam traps contain a valve that is opened and closed by the differential expansion of metallic disks.

Bimetallic steam traps are used in many industrial and commercial applications in the chemical processing, energy production, food processing, HVAC, pulp and paper, mining, petro-chemical and pharmaceutical industries.

Here is a video that illustrates how a bimetallic steam trap works. It shows the thermostatic principal involved and how two bimetallic plates interact and provide physical movement to open and close a valve seat to discharge condensate.