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Strainers and Self Cleaning |
Y- Strainer
Y- Strainer is a device which provides a means of mechanically removing solids from a flowing fluid, gas or Steam by utilizing a perforated, mesh or wedge wire straining element. They are employed in pipelines to protect downstream mechanical equipment such as condensers, heat exchanges, pumps, compressor, flowmeters, spray nozzles ,turbines, steam traps, etc. from the detrimental effect of sediment, rust, pipe scale or other extraneous debris.
Y- Strainers can be used in horizontal as well as vertical unlike other strainers. Special attention must be given, however, to maintaining the position of the debris collection chamber and the drain (blow down) connection in their lowest position. A “Y” strainer in vertical piping must be placed with its screen in the downward position to trap the sediment in the debris collection chamber. For applications with heavier dirt loading, Y-Strainers can be fitted with a "blow-off" connection that permits the screen to be cleaned without removing it from the strainer body.
In addition to basic material of construction, we offer in special metals such as Monel, Inconel, Hastalloy, Duplex stainless steel, Aluminum Bronze and other alloy steel Screwed ends, Socket ends, Butt weld ends and Flanged ends are available. End connections are flanged and screwed to international Standards including ANSI, BS10, BS4504, DIN and API, NPT. Sizes from 0.5" (15mm) to 20"+ (500mm+) and Maximum pressure ratings API 10,000lbs
Hydrotherms are increasingly aware of the problem of high differential pressure drops caused by some manufacturers reducing the size of their strainer bodies to save materials and cut costs. That is why Hydrotherms supply units with generous ratios of filtration area to pipe bore area to prevent flow restriction.
Basket / Simplex Strainers
Simplex Basket Strainers provide a simple and efficient method of protecting vital pipeline equipment and reducing expensive plant maintenance. Their advantages include positive retention of debris, simple installation and minimal pressure drop characteristics due to a design which gives a generous ratio of filtration area to pipe bore area.
Simplex Basket strainer will generally create less pressure drop than a “Y” type strainer in sizes above 4". Simplex strainers have been designed with open area, or straining ratios, of at least 5:1. On the other hand, Y strainers usually have a 2:1 straining ratio. Basket strainers are not normally constructed for pressures above 1,500 psi.
Simplex Basket strainers are used for batch operations where the liquid flow may be interrupted periodically for cleaning. They are generally recommended for intermittent service such as fluid system start-ups, emergency protection and light duty operations where the amount of foreign debris is small.
Sizes: 0.5" (15mm) to 78"+ (1980mm+)
Flanged Ends ANSI, BS4504, DIN, BS10, JIS
BW Ends from Schedule 40 to Sch 100 and + Special Schedule
Maximum pressure rating class 1500lb+
Carbon Steel, Low Temperature Steel, S/S, Duplex S/S Alloy Steel or other materials available
Tee Strainers
TEE strainers intended for service similar to temporary conical strainers but with their own element housing. Specifically designed for location into a pipe work system that cannot be split to extract the screen after commissioning is complete, or where the strainer is to be left installed as an additional permanent safeguard. They can be mounted into vertical or horizontal piping and can be configured for right-angled applications and the strainer screen can be cleaned without draining the strainer housing. The unrestricted flow path in tee strainer results in a very low pressure drop compared to other types of strainers. Units may be flanged or welded into the line and the screen is extracted through the branch opening. Each unit is provided with a flanged cover as standard. Davit arm assembly and quick opening closures available on demand.
Sizes: 0.5" (15mm) to 30"+ (750mm+)
Flanged Ends ANSI, BS4504, DIN, BS10, JIS
BW Ends from Schedule 40 to Sch 100 + Special Schedule
Carbon Steel, Low Temperature Steel, S/S, Duplex S/S Alloy Steel or other materials available Maximum pressure rating class 2500lb+ (172 BarG)
Duplex Strainer
Duplex Strainer or Twin basket strainer can be used where continuous operation is required and the line cannot be disassembled for cleanout. Examples are fuel oil strainers for industrial or marine oil burners, lubricating lines on board ships, cooling towers, continuously running chemical operations, and many industrial water intake and service lines. When one basket becomes full, the flow is switched to the other basket. The first basket is removed, cleaned and replaced. In Duplex Strainers because of the more circuitous path, pressure drop is higher than through the equivalent size single basket strainer.
Sizes: 4" (100mm) to 48"+ (1200mm+)
Flanged Ends ANSI, BS4504 (DIN, PN), BS10
100% shut-off for gas applications
Actuated changeover available
Various materials of construction
Various materials of construction
Quick release or bolted covers
Skid bases and framework also available
Maximum pressure ratings ANSI Class 300lb
An automatic self-cleaning strainer is a unit which goes through a complete cleaning cycle, using some of the fluid flowing through the strainer to flush out the collected debris, with little or no attention by the plant personnel.
Automatic strainers are normally more expensive than the manually cleaned units but their extra cost can often be justified for one or more of the following reasons:
- The frequency of cleaning of a manual unit and the cost of labor for doing this.
- If there is any danger that the strainer or the equipment that it is protecting may be damaged by the strainer not being cleaned when required.
- The strainer is necessarily located in a place where it is not readily accessible for cleaning.
- Plugging of the strainer is unpredictable due to a variable loading rate such that manual cleaning cannot be properly scheduled.
- Insufficient available personnel for manual cleaning.
There are many types of automatic and semi-automatic controls for the strainer and among these are:
- Differential pressure switch which senses the pressure drop through the strainer and initiates a cleaning cycle at a preset pressure differential.
- Timer which initiates cleaning cycle of strainer at preset intervals of time.
- Pushbutton start for which an operator pushes a button to initiate a cleaning cycle (semi-automatic).
- Differential pressure switch alarms which signal the operator that the strainer needs cleaning (semiautomatic).
- Any combination of the above controls.
All of the above control systems are normally used with strainers that clean intermittently. Some automatic strainers also clean continuously so that a control to initiate the cleaning cycle is not required.
For intermittent cleaning strainers, the differential pressure switch control is normally preferred, because it will initiate a cleaning cycle when required regardless of strainer plugging rate. If a fairly constant strainer plugging rate occurs, the timer control can be utilized. Also, if the strainer may go through long periods of slow plugging during which it may not clean, a timer control may be desired to make certain the strainer operates periodically to keep it from binding. Normally, because of its automatic cleaning characteristic, an automatic strainer is cleaner for longer periods of time, than a manually cleaned strainer.
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