Product Range
Select a series for detailed specifications, downloads and technical data.
Basket Strainer
Quick Specs Size: 1/2" - 24" (DN15 - DN600) Pressure: Class 150 - 300 / PN 10-40 Standard: MSS SP-89, ASME B16.34, ASME B16.5 (flanged) Body Materials: A216 WCB, A351 CF8M, A351 CF8, cast iron (GG25), ductile iron (GGG40) Screen: Perforated stainless steel (304/316) or monel screen, mesh sizes from 1/32" to 1/2" perforations, optional fine mesh wire screen insert (20-200 mesh) Design: Horizontal or vertical installation, bolted cover with gasket, basket/screen removable through top cover opening, drain plug on body bottom, flow direction: inlet through screen → outlet Why Basket Strainers Dominate Pump Protection Pumps eat debris. Valve seats get scored. Heat exchanger tubes plug up. Every one of these traces back to the same cause—something got past the inlet that shouldn't have been there. A basket strainer sits between the contamination source and the equipment that can't tolerate it. Fluid enters the body, hits the screen outside-in, debris collects inside the basket, clean fluid passes through. Simple. The reason basket strainers dominate pump duty isn't complicated: open-top access. Unbolt the cover, lift the basket, dump the debris, rinse it, drop it back in, bolt the cover down—five minutes. No pipeline disconnect. No shutdown cycle. You see what you're catching—pipe scale, gasket fragments, construction trash. When you know what's in the basket, you know what's in your process. Screen selection matches the threat. Coarse perforations—1/8" to 1/2"—for pump protection on water and general process lines. These catch the big stuff: weld beads, rust flakes, gasket pieces. Fine mesh, 40 to 100 mesh, for instrument protection and spray nozzle duty. Match the mesh to what you need to stop, not to the finest screen available. Body Material—Don't Overspec, Don't Underspec Carbon steel (WCB) covers general service—water, oil, non-corrosive process, Class 150 and 300. Stainless (CF8M / 316) handles corrosive media—seawater, chemical lines—where carbon steel pits in two years. Cast iron (GG25) lands in low-pressure water where cost beats corrosion resistance—building HVAC, municipal water, irrigation. Ductile iron (GGG40) bridges the gap: stronger than cast iron, cheaper than steel, good enough for a lot of industrial water duty. A CF8M body on a clean-water HVAC line is money wasted. A GG25 body on a seawater intake is a two-year replacement cycle. Get the material right for the service. FAQ A: Yes—with flow downward. The basket works the same way. Vertical upward flow works too, but debris can fall back into the outlet when you pull the basket. Horizontal or downward-vertical is preferred. A: Perforated screen alone for coarse filtration—pump protection, general debris. Add a mesh wire insert inside the perforated basket for fine filtration—instrument protection, spray nozzle protection, particles smaller than 1/32". The perforated basket provides structure; the mesh provides fine filtration. A: Depends on debris loading. Clean water—weekly or monthly. Commissioning with construction debris—check daily until the system runs clean. Heavy loading—install a differential pressure gauge and clean when the drop exceeds your threshold. A: Clean basket—0.5 to 2 psi, depending on flow rate and mesh. As debris loads the screen, drop increases. That's your cleaning signal. If clean-basket drop exceeds your tolerance, the mesh may be too fine for the flow rate. A: Yes—rated for permanent service. Not a temporary strainer. The body, flanges, pressure rating, and gasketed cover are designed for continuous duty.
Sight Glass
Quick Specs Size: 1/2" - 8" (DN15 - DN200) Pressure: Class 150 - 300 / PN 10-40 Standard: MSS SP-97, manufacturer-specific Body Materials: A216 WCB, A351 CF8M, cast iron (GG25), ductile iron (GGG40), bronze/brass for small sizes Glass: Borosilicate glass (tempered), optionally armored with steel protective shield. Glass disc mounted between body flanges with PTFE/EPDM gaskets on both sides. Design: Flat glass window(s) in the body—single-window or dual-window (opposing sides for backlit visibility). Fluid passes through the straight-through bore; operator observes flow through the glass window. No moving parts inside the flow path. Where You Need to See What's Happening Process lines run inside closed pipes—you can't see the fluid. Whether it's flowing or stopped, clear or cloudy, the right color or off—instruments give you numbers, not pictures. Sight glasses give you a visual window—flow confirmation, condition checking, gas detection, all through a glass panel in the body. Install where you need to confirm flow—pump discharge, control valve downstream, return lines where no-flow means trouble upstream. Install where you need to check condition—chemical process lines where color shows reaction progress, cooling returns where cloudiness means contamination, condensate where steam carryover shows as bubbles. Install where you need to detect gas—pump suction lines where air means cavitation risk, liquid distribution where gas pockets mean uneven delivery. Borosilicate glass handles -50°C to +250°C for standard grades—covers most process applications. Specialized compositions go higher for hot oil and thermal fluid. The glass is tempered—resists thermal shock and normal handling impact. It doesn't resist a wrench dropped from six feet—but that's not the operating environment. Single vs. Dual Window—Dark Fluids Need Backlight Single-window: one glass panel—look through it and see the fluid. Works for clear fluids where ambient lighting provides enough visibility. Dual-window: opposing panels on both sides—shine light through one, observe from the other. Backlit visibility through dark or opaque fluids. Essential for heavy oil, dark chemical streams, slurry lines—a single window on dark fluid shows a dark rectangle with zero information. Don't skip dual windows on dark-fluid lines because they cost more—a single window on heavy oil is a sight glass that can't do its job. Dual costs 20—30% more and actually works—buy the one that works. FAQ A: Standard borosilicate: -50°C to +250°C—specialized compositions go higher. Gasket material also limits the range—PTFE handles higher temps than EPDM. Select both glass and gasket for the process temperature, not just the glass. A: Single—water is clear enough that ambient light provides sufficient visibility. A: No fixed interval—replace when visibility is insufficient from scratching, etching, or obscuring. Clean water: years. Corrosive media or abrasive slurries: months—inspect during scheduled shutdowns. Inspect during scheduled shutdowns. A: With caution—borosilicate handles the temperature, but steam means thermal cycling, condensate on the glass, thermal shock risk. Use PTFE or graphite gaskets rated for steam—consider armored glass for the containment benefit. Inspect more frequently than on liquid service. A: Minimal—straight-through bore, no restrictions, no screen, no internal elements. Drop is essentially the same as straight pipe of the same length.
Duplex Basket Strainer
Quick Specs Size: 2" - 24" (DN50 - DN600) Pressure: Class 150 - 300 / PN 10-40 Standard: MSS SP-89, manufacturer-specific for duplex strainers Body Materials: A216 WCB (cast carbon steel), A351 CF8M (cast stainless 316), A351 CF8 (cast stainless 304), ductile iron (GGG40) Straining Element: Perforated screen or mesh-lined basket. Screen perforation 0.5mm - 6mm. Mesh 20 - 200 mesh. Basket material matches body. Design: Two parallel chambers with diverter valve (plug or ball). Continuous-flow operation — zero line shutdown for basket maintenance. Why Two Chambers Matter Some lines just can't stop. Chemical processing plants running continuous reaction loops — you shut the feed line for thirty minutes to clean a strainer basket and the whole batch is compromised. Power plant cooling water circuits pulling from rivers and lakes — debris loads spike after storms and that single basket strainer clogs fast, but the turbine doesn't pause because the strainer needs cleaning. Refinery fuel oil circulation, offshore seawater injection — these systems run around the clock because stopping them costs real money or creates real hazard. That's the entire reason duplex strainers exist. One chamber handles the flow. The other chamber sits isolated, waiting. When the active basket fills and your pressure differential starts climbing, you don't shut anything down. Turn the diverter valve. Flow shifts to the clean chamber in seconds. The dirty chamber is now isolated — open the cover, pull the basket, clean it, put it back, close the cover. The line never stopped. Production never paused. Inside the Diverter Valve The diverter valve is what makes a duplex strainer work, and the choice between plug and ball matters more than most spec sheets admit. Plug valve diverters give you tight shutoff between the two chambers. The plug seats hard against the body — metal-to-metal contact that seals reliably even when debris is present in the flow. But turning a plug valve takes more force, especially at larger sizes. If you're specifying a manually operated duplex strainer above 8" with a plug diverter, the operator needs leverage. That means longer handles, more physical effort, and in some installations you'll want an actuator instead of a handwheel. Ball valve diverters turn easier. A quarter-turn and you've switched chambers. The force requirement is lower, which makes ball diverters popular on manually operated units. The tradeoff is sealing. Ball-to-body contact does the isolation between chambers, and in dirty service — abrasive particles, slurry, high-debris loads — that sealing surface can wear. It's not a failure, it's a gradual degradation. The chambers start to leak into each other and you lose the clean isolation you need for safe basket removal. Either design works. The question is what's in your flow stream and how you want to actuate the switch. Clean water service with occasional debris — ball diverter, easy turn, perfectly adequate. Heavy debris loading or abrasive media — plug diverter, tighter seal, more turning force. Size above 12" and you probably want actuated switching regardless of valve type. Size and Cost Reality At sizes above 12", duplex strainers get expensive fast. Two full-size cast bodies, a diverter valve mechanism machined into the connecting passage, four cover assemblies, and all the internal basket seating. You're buying two strainers bolted together with a switching mechanism in the middle — and that's exactly what the price reflects. But for applications where a single basket strainer's periodic shutdown is unacceptable, the duplex is the only continuous-filtration option at process-line scale. There's no cheaper alternative that gives you uninterrupted flow with basket access. The duplex strainer costs more because it solves a problem that can't be solved any other way. FAQ Yes, but the diverter valve orientation matters. Vertical installation with flow going upward — make sure the diverter valve shaft is horizontal so gravity doesn't bias the valve position. Vertical downward flow works too, but you need to confirm with the manufacturer that the basket seating design handles the reverse-flow load direction. Most standard duplex strainers are designed for horizontal installation; vertical installs are possible but require layout review. Pressure differential. Install a DP gauge or transmitter across the active chamber. When the differential hits your set threshold — typically 5-15 psi above clean-basket baseline, depending on your flow conditions — that's your switch point. Some operators switch on a time schedule instead, but pressure differential is the reliable indicator because debris loading varies with actual conditions, not with your calendar. They should be. The two chambers alternate — if chamber A has a 40-mesh basket and chamber B has a 100-mesh basket, you're getting inconsistent filtration every time you switch. Same mesh, same perforation size, same basket design in both chambers. That way the product quality downstream doesn't change when you flip the diverter valve. Depends entirely on your debris load. Light debris in clean water service — you might switch chambers once a week. Heavy debris in river water or process slurries — multiple switches per day. The point of the duplex design is that maintenance frequency doesn't dictate process downtime. Clean the basket whenever it needs cleaning. The other chamber keeps the line running. Yes. Electric or pneumatic actuators mount on the diverter valve shaft. Automated switching tied to a DP transmitter lets the strainer switch chambers without operator intervention — the DP signal triggers the actuator, flow shifts, the dirty chamber waits for manual basket cleaning. Automated duplex strainers are common in unmanned installations and remote process stations where operator access is limited.
Y-Strainer
Quick Specs Size: 1/2" - 12" (DN15 - DN300) Pressure: Class 150 - 1500 / PN 10-250 Standard: MSS SP-89, ASME B16.34, ASME B16.11 (socket weld / threaded ends) Body Materials: A216 WCB, A351 CF8M, A182 F316 (forged), A182 F304 (forged), brass/bronze for small sizes Screen: Perforated stainless steel cylinder, mesh sizes from 1/64" perforations to coarse 1/4", optional fine mesh wire insert Design: Y-shaped body—angled screen chamber branches off the main flow passage. Screen sits in the angled leg, removable through a bolted plug or flanged cover on the branch end. Threaded, socket weld, or flanged end connections. Where the Y-Strainer Fits and the Basket Doesn't Small-diameter lines—1/2" through 4"—don't have room for a basket strainer. The body cavity on a 2" basket is already bulky. At 1" it's disproportionate to the pipeline. The Y-strainer's angled screen chamber branches off the main flow—so the body is shorter and lighter at the same size. That compact geometry makes Y-strainers the default for small-bore protection. Then there's pressure. High-pressure steam, compressed air, hydraulic circuits run at pressures a basket chamber struggles to handle economically. A forged Y-body with a cylindrical screen rates to Class 1500 without the cost penalty of a heavy basket chamber at the same rating. Simple geometry, simpler stress, lower cost at high pressure—that's why you see Y-strainers on steam, not basket strainers. The screen is a cylinder—fluid passes outside-in, debris collects inside. You remove the bolted plug on the branch end to access the screen. The opening is smaller than a basket strainer's top cover, and you're working at an angle. Less convenient, but the pressure rating and footprint make the tradeoff worth it—Y-strainers belong where basket strainers can't fit. Steam, Air, and Hydraulic—Where Y-Strainers Live Steam lines carry condensate, rust, pipe scale—all of it headed for your control valves. A Y-strainer on the supply catches it before it reaches control valves, reducing valves, and steam traps. Forged steel handles the temperature and pressure. Stainless screen handles corrosion. Flanged or socket-weld connections seal against steam leakage. Compressed air picks up pipe dust, compressor oil carryover, desiccant dust. Y-strainers on the air supply protect pneumatic instruments and air-operated valves. Small sizes—1/2" to 2"—with threaded or socket-weld ends, brass or forged steel depending on air quality requirements. Hydraulic circuits are the toughest application. Fine mesh—60 to 100 mesh—protects servo valves and proportional valves from particulate that scores valve lands and causes erratic operation. Forged F316 bodies handle the fluid without contamination. The compact Y-body fits into tight manifold installations where a basket strainer can't be routed. FAQ A: You can on sizes 4" and up, where the pipeline footprint fits. Below 4", the basket body is oversized relative to the line and the cost per inch climbs. Y-strainers are the practical choice for small-bore and high-pressure duty. A: Yes—forged steel (F304/F316, or WCB for lower-pressure steam) is standard on steam distribution. Select the body for temperature and pressure class. Stainless screen handles corrosion. Ensure the branch plug gasket is rated for steam—PTFE or graphite, not EPDM. A: Threaded (NPT/BSP) for low-pressure, small-diameter service where disassembly is expected—compressed air, water. Socket-weld for higher pressure or temperature where a permanent leak-tight connection is needed—steam, hydraulic, chemical. Socket-weld means permanent install—you maintain through the branch-end access only. A: Perforated screen down to 1/64" perforations. Fine mesh wire inserts from 20 to 200 mesh. Finer mesh loads faster. Match the mesh to downstream equipment tolerance—don't filter finer than necessary. A: No—blowdown flushes light debris through a valved port. It extends the interval between full screen removals on moderate-loading lines. Heavy loading or fully plugged screens still require manual removal and cleaning.
Quick Open Basket Strainer
Quick Specs Size: 2" - 12" (DN50 - DN300) Pressure: Class 150 - 300 / PN 10-40 Standard: MSS SP-89, manufacturer-specific for quick-open cover designs Body Materials: A216 WCB, A351 CF8M, A351 CF8, ductile iron (GGG40) Straining Element: Perforated basket with mesh lining option. Screen perforation 0.5mm - 6mm, mesh 20 - 200 mesh. Cover: Quick-open mechanism — swing-away with toggle clamp, davit-arm with handwheel, or bayonet-style rotation. Opens in 5-10 seconds. No bolt removal. Design: Same internal geometry as standard basket strainer. Quick-open cover replaces bolted cover for faster basket access. The Bolt Problem Standard basket strainer covers hold pressure with bolts — 8 to 16 of them depending on size and pressure class. Cleaning cycle on a bolted cover strainer goes like this: loosen every bolt, lift the cover off, pull the basket, clean it, reinstall the basket, set the cover back on the gasket, thread every bolt, torque them in sequence to seat the gasket evenly. Fifteen to thirty minutes per cycle. In light debris service you do this once a month and the time cost is manageable. But when the basket fills every few hours — river water intakes pulling silt and organic matter, pulp stock lines with fiber accumulation, abrasive slurry circuits where the screen loads up fast — that fifteen-to-thirty minute interval stacks up over a week. Hours of downtime. Hours of maintenance labor. All spent on bolt management instead of actual strainer cleaning. Quick-open covers eliminate the bolt cycle entirely. Swing the cover away on a hinge arm. Toggle clamps release the seal and the cover swings open — five seconds. Pull the basket, clean it, push it back, swing the cover closed, snap the toggle clamps shut. Ten seconds total for the cover operation. No bolt removal, no torque sequencing, no gasket alignment on reassembly because quick-open covers use O-ring or self-sealing gasket designs that seat automatically when the clamps engage. Three Ways to Open Fast Swing-away covers with toggle clamps are the most common quick-open design. The cover hangs on a hinge arm attached to the strainer body. Toggle clamps — usually two or four depending on size — pull the cover tight against the sealing surface. Release the clamps, the cover swings open like a door. Fast, simple, and the cover never leaves the strainer — no lifting, no setting it down somewhere and misplacing it. Works well at sizes 2" through 8" where the cover weight is manageable. Davit-arm covers use a handwheel to lift the cover straight off the body. The davit arm is a rigid support mounted on the strainer body — you crank the handwheel and the arm lifts the cover away, then swings it aside for basket access. Davit-arm designs handle heavier covers at larger sizes — 10" and 12" strainers where a swing-away cover gets too heavy to manage comfortably by hand. Bayonet covers rotate to lock and unlock. Turn the cover 60 to 90 degrees and the locking lugs disengage — lift the cover off. No bolts, no clamps, no hinge mechanism. The simplest quick-open design mechanically, but it requires lifting the cover clear of the body rather than swinging it aside. Bayonet covers are common on smaller sizes where the cover is light enough to handle easily. What You Pay for Speed Quick-open covers cost two to three times more than standard bolted covers. The hinge mechanism, toggle clamps, davit arm, or bayonet locking ring — these components add machining complexity and material cost. The self-sealing gasket design (O-ring groove in the cover or body face) costs more to manufacture than a flat gasket surface that relies on bolt compression. There's also a pressure rating consideration. Bolted covers distribute seating force evenly around the full circumference — every bolt contributes equal compression to the gasket. Toggle clamps concentrate force at two or four points. At Class 150 and Class 300 in sizes 2" through 12", the seating force from toggle clamps is adequate — the O-ring or self-sealing gasket compensates for the uneven force distribution by conforming to the sealing surface under internal pressure. But at higher pressures or larger sizes, bolted covers are the safer engineering choice. The quick-open cover design has a practical ceiling, and that ceiling is roughly Class 300 at 12" for most manufacturers. The cost justification comes from the cleaning frequency. If you're cleaning the basket once a month, a bolted cover is fine — the time cost is negligible. If you're cleaning every shift or every few hours, the labor and downtime savings from quick-open covers pay back the higher purchase price within weeks. Ten to fifteen times faster per cleaning cycle. Multiply that across daily or weekly cleaning frequency and the math is clear. FAQ Usually not. Quick-open covers require specific body casting geometry — O-ring grooves, hinge mounting pads, clamp attachment points, or bayonet locking seats. Standard bolted-cover strainer bodies don't have these features. Retrofitting means replacing the body along with the cover, which is essentially buying a new strainer. Check with your manufacturer — some offer conversion kits for specific body designs, but it's not common. At Class 150-300 in the 2"-12" range, yes. The O-ring or self-sealing gasket design seats under internal pressure — the process pressure itself helps maintain the seal. Bolted covers with flat gaskets rely entirely on bolt compression, which can relax over time as gaskets compress and bolts lose preload. Quick-open O-ring seals actually maintain their seating force better under sustained pressure because the process pressure reinforces the seal. At higher pressures, bolted covers regain the advantage. O-ring seals are standard — elastomer O-rings seated in a machined groove on the cover face or body face. Some designs use self-sealing flat gaskets with a raised sealing bead that compresses under clamp force and internal pressure. Both designs are single-component seals — replace the O-ring or gasket during basket cleaning if it shows wear, damage, or hardening. No multi-bolt gasket seating sequence required. Toggle clamps are mechanical components with moving parts — pivot pins, springs, and latch mechanisms. In normal service they last years. In corrosive environments or high-cycle applications (daily or multiple daily opening), inspect the clamps during each cleaning and replace any that show corrosion, spring fatigue, or latch wear. Replacement toggle clamps are standard parts available from the strainer manufacturer. Yes. Same perforated basket design, same mesh lining options, same seating geometry inside the body. The quick-open cover changes the access method, not the filtration function. You can use the same basket specifications — perforation size, mesh size, material — that you'd specify for a standard bolted-cover basket strainer at the same size and service conditions.
Flat Temporary Strainer
Quick Specs Custom-fitted to pipe inside diameter — common range 2" to 24" Class 150–300 / PN 10–40 (temporary service only — not rated for permanent installation) Project-specific fabrication — no industry standard governs temporary strainer geometry A240 304 / A240 316 stainless plate — disc and flange ring cut from rolled plate, no cast body Flat perforated disc — perforation 1mm to 6mm, mesh lining optional (20–100 mesh) Flat disc fits between pipeline flanges, perpendicular to flow — debris collects on upstream face, removed after commissioning Why Most Projects Start With a Flat Disc When a new pipeline goes live, debris is guaranteed — welding slag, rust chips, dirt, gasket fragments. Something has to catch that junk before it reaches downstream valves, pumps, and instruments. The flat temporary strainer is what most project teams reach for first, and the reason is straightforward: it works, it's cheap, and it installs in minutes. You cut a disc from perforated plate, add a flange ring or welding tabs, and you're done. No forming. No rolling. No cone geometry math. On a big construction project — hundreds of pipe runs, dozens of sizes, commissioning deadlines breathing down your neck — that fabrication simplicity matters. Every flat disc you order costs less and ships faster than a conical equivalent. When the schedule is tight and the budget is real, the flat disc wins on logistics alone. Installation is just as easy. Pull the flange bolts, slip the disc in with gaskets on both sides, re-torque. The disc is thin — 3 to 6mm plate — so it barely changes the flange gap. Two weeks later when the line is clean, pull the bolts again, take the disc out, replace it with a permanent spacer or gasket. No special tools. No drama. The whole cycle from install to remove takes less time than reading the commissioning procedure. Then there's the space advantage. Flat discs occupy almost no axial room — just disc thickness plus two gaskets. In tight installations where flanges sit close together and there's no room for a conical strainer's extended body, the flat disc fits without re-piping anything. That's not a small thing on congested plant layouts where every inch of pipe rack matters. Where the Flat Disc Hits Its Limit Here's the honest tradeoff. A flat circle has less surface area than a cone wrapped around the same pipe diameter. Less surface means higher pressure drop per unit of debris caught — the disc clogs faster under the same loading conditions. And flow distribution isn't even. Incoming velocity hits the disc center first, loading debris there while the outer perimeter sees less action. Localized clogging at the center is a real pattern — not a theory, it's what operators see in the field. For light debris loading or short startup runs where you'll pull the strainer before it ever clogs, those tradeoffs don't matter. The flat disc does the job at lower cost and simpler fabrication. But if you're facing heavy debris — say a long commissioning period on a rusty old line tied into new piping — the conical temporary strainer's larger surface area and better flow distribution give you more operating margin. More room before clogging means less risk of an unplanned shutdown during the most schedule-sensitive phase of the project. Know your debris loading. Know your timeline. Pick the shape that matches both. What the Materials Actually Mean A240 304 and 316 plate — that's the source material for everything on a flat temporary strainer. The disc is cut from perforated plate. The flange ring is cut from solid plate of the same grade. There's no cast body, no forging, no complex machining. It's fabricated from rolled plate stock, which is why it's fast to produce and why material traceability stays clean — one heat number, one grade, one Certificate of Material compliance. Mesh lining is optional. If your downstream equipment is sensitive — fine-bore control valves, metering orifices, precision pump internals — you add a mesh liner over the perforated disc to catch finer particles that slip through the 1mm to 6mm round holes. Mesh ranges from 20 to 100 mesh. For rough startup protection where you just need to catch welding beads and rust flakes, bare perforated plate is enough. Don't over-spec the straining element for a two-week temporary installation — match it to what's actually in the pipe. FAQ A: No. It's designed for startup and commissioning service only — typically 2 to 4 weeks. Permanent installation means continuous debris loading with no removal plan, and the flat disc isn't built for that. After commissioning, remove the strainer and install a permanent gasket or spacer ring. A: The disc sits between two flanges with gaskets on both sides — one gasket upstream, one downstream. Bolt the flanges back together and torque to specification. The disc thickness (3–6mm) plus two gaskets is within normal flange gap tolerance for Class 150 and 300 joints. A: When debris loading is heavy, the commissioning period is long, or the line runs continuously before strainer removal. The cone offers more perforated surface area and better flow distribution — more margin before clogging. If your startup is short and debris is light, the flat disc is the practical choice. A: Match it to the smallest opening in your downstream equipment. If a control valve has a 3mm trim passage, don't use 6mm perforations — debris that passes the strainer will jam the valve. A common rule of thumb: perforation diameter should be no larger than two-thirds of the smallest downstream clearance. Add mesh lining if you need finer capture than round perforations allow. A: Most are fabricated to order — custom-sized to match the specific pipe bore where they install. No industry standard governs the geometry, so each one is a project-specific fabrication item. That said, the simple flat disc design means short fabrication lead times compared to conical or other custom shapes.
Conical Temporary Strainer
Quick Specs Size: Custom-fitted to pipe inside diameter — manufactured to match specific pipe ID. Common range covers 2" - 24" pipe sizes. Pressure: Class 150 - 300 / PN 10-40 (temporary service only — not rated for permanent installation. Design pressure matches line pressure for startup/commissioning period only) Standard: No industry standard governs temporary strainer geometry — project-specific fabrication items per project piping specifications. MSS SP-89 covers permanent strainers only. Body Materials: A240 304 (stainless 304 plate), A240 316 (stainless 316 plate). No cast body — fabricated from rolled plate. Straining Element: Perforated cone surface. Perforation 1mm - 6mm, mesh lining optional (20 - 100 mesh). The cone shape is the straining element — flow passes through perforated cone wall from outside to inside. Design: Cone-shaped perforated screen installed between pipeline flanges during commissioning. Apex points downstream. Removed after 2-4 weeks when initial debris is cleared. Flange-mounted or welded-tab installation. What's Inside a New Pipeline Every new piping system has debris inside it. No matter how carefully the construction crew works — welding, cutting, grinding, fitting — the inside of a newly assembled pipe system contains material that shouldn't be there. Welding slag drops inside the pipe from root-pass welding. Cutting chips from pipe preparation with saws or grinding tools. Gasket fragments from alignment and bolting. Dirt and dust that entered during storage and handling. Rust scale forming on carbon steel pipe surfaces during the weeks or months between fabrication and commissioning. This debris load during startup is ten to a hundred times heavier than the normal operating debris that permanent strainers handle. Permanent strainers — basket strainers, Y-strainers, duplex strainers — have screens sized for ongoing operational conditions. Sand particles, corrosion products, biological growth, process contaminants. Those screens run at 0.5mm perforation or 40-mesh lining or finer. If you put that fine screen into a line during startup, it clogs in hours. Sometimes in minutes. The startup debris is larger, more varied, and far more abundant than anything the permanent strainer was designed to catch. Conical temporary strainers exist to handle this startup load. Larger perforations — 1mm to 6mm — pass the volume of startup debris without immediate clogging while still catching the big pieces that damage downstream equipment. Welding slag, cutting chips, gasket fragments, large rust flakes. The cone strainer catches what matters during commissioning and lets the smaller particles pass through to be flushed or handled by the permanent strainer once it's installed after startup. Why a Cone, Not a Flat Screen The cone shape does two things that a flat screen can't. Surface area. A cone sitting inside a pipe has more perforated surface than a flat disc at the same pipe diameter — roughly 1.5 to 2 times more depending on cone length. More surface area means more open area for flow to pass through. More open area means lower pressure drop per unit of debris collected on the surface. During startup, when debris loading is heavy and continuous, that extra surface area keeps the strainer functional longer before it needs cleaning or removal. Flat screens load up fast because all the debris collects on a small surface and blocks the perforations quickly. Flow distribution. The cone shape spreads incoming flow across the perforated surface. Flow enters from upstream, hits the cone apex first, and spreads outward along the cone wall toward the base. The velocity distributes across the full cone surface rather than concentrating at the center. Flat screens create a different flow pattern — the highest velocity core stream hits the screen center and debris loads there first while the outer edges see lower velocity and slower loading. Localized clogging at the center blocks a disproportionate share of the open area. The cone shape avoids this concentration effect by geometry alone. Temporary Means Temporary Conical temporary strainers are not permanent piping components. The perforation sizes are too coarse for ongoing operational straining — 1mm to 6mm perforation won't catch the fine particles that your permanent strainer handles. The fabricated plate construction — rolled and welded perforated sheet — doesn't have the structural durability for years of continuous pressure service. Cast strainer bodies with machined seating surfaces and rated cover assemblies are built for permanent installation. Conical temporary strainers are built for a commissioning window. After two to four weeks of service, pull the conical strainer out of the line. Open the flange joint, remove the strainer and its gaskets, inspect the pipe interior for remaining debris. If the system is clean — no visible welding slag, no cutting chips, no gasket material — install the permanent strainer or run the line unstrained per project specification. If debris is still present, extend the temporary strainer service period and keep monitoring. Don't leave a conical temporary strainer in the line indefinitely. It's a startup tool, not an operating component. FAQ Match the perforation to the debris you need to catch, not to the final operating filtration requirement. Startup debris — welding slag, cutting chips, gasket pieces — is typically 2mm and larger. A 3mm perforation catches these while allowing smaller particles to pass for flushing downstream. If your downstream equipment is sensitive to particles above 1mm, use 1mm perforation on the cone and accept that it will clog faster during startup — you'll need to monitor and clean it more frequently during the commissioning period. Optional. Mesh lining (20-100 mesh) adds finer filtration on top of the perforated cone surface. Use it when your downstream equipment needs protection from smaller particles during startup and you can't wait for the permanent strainer installation. Mesh lining reduces open area and increases clogging rate — the cone loads up faster and needs more frequent inspection during commissioning. For most startup applications, perforated cone surface without mesh lining is adequate because the permanent strainer handles fine filtration after the temporary strainer is removed. Flange-mounted: the conical strainer sits between two pipeline flanges with a gasket on each side. The flange bolts compress the strainer and gaskets together. This is the standard installation method — easy to inspect, easy to remove, no welding required. Welded-tab: the strainer has small tabs that are welded to one flange face to hold position during service. After commissioning, you cut the tabs off and remove the strainer. Welded-tab installation prevents the strainer from shifting or blowing out under high flow conditions, but it requires welding during installation and cutting during removal. Most projects use flange-mounted installation unless the flow conditions or safety review specifically require welded retention. Sometimes. Inspect the perforated surface for damage, deformation, or corrosion after removal. If the cone is intact — no crushed perforations, no weld cracks, no material degradation — clean it and store it for reuse on a similar-size line. But conical strainers are custom-fitted to specific pipe IDs, so reuse only works if the next project has the same pipe diameter and flange dimensions. Many projects treat conical temporary strainers as single-use items because the fabrication cost is low relative to the inspection, cleaning, and size-matching effort required for reuse. Two to four weeks for most installations. Monitor pressure differential across the cone during commissioning — if the differential stays low and stable after the first week, the debris load is clearing. After two weeks with stable DP, schedule removal and inspection. If the differential continues climbing after two weeks, the system still has significant debris and the cone should stay in longer. Don't extend beyond four weeks without engineering review — the temporary strainer isn't designed for extended service, and a loaded cone at elevated DP is a flow restriction that affects system performance.
Technical Overview
Strainers remove debris from process fluid before it reaches downstream equipment—pumps, control valves, heat exchangers, spray nozzles, instrumentation. Sight flow indicators let operators visually confirm process conditions—flow presence, flow direction, fluid clarity, entrained gas, reaction progress. These two product families serve different functions but share the same installation context: they sit in the pipeline as inline components, between the source and the sensitive downstream equipment that debris or unexpected process conditions would damage. FLOWKS manufactures five strainer configurations and two sight flow indicator configurations. Basket strainers use a cylindrical or basket-shaped screen inside a body cavity—debris collects inside the basket, clean fluid passes through to the outlet, top-cover access makes basket removal a five-minute job. Y-type strainers use a compact angled screen chamber branching off the main flow passage—smaller, lighter, rated to Class 1500 at small sizes, the default for steam, air, and small-bore process protection. Dual basket strainers add a diverter valve between two parallel chambers—switch flow from one to the other without shutting down the line. Duplex basket strainers upgrade the changeover to a four-port or six-port integral valve that simultaneously swaps inlet and outlet in one lever turn, with bleed/vent ports for safe offline maintenance. Temporary strainers are commissioning-only components—perforated cones or flat plates installed between pipeline flanges to catch construction debris during start-up, removed after the system is clean. Window-type sight glasses provide a borosilicate glass panel for visual observation—single or dual-window for backlit visibility. Flapper/ball-type sight flow indicators add an internal moving element that deflects with flow direction and velocity, giving visual confirmation of flow presence, direction, and relative rate in addition to fluid appearance.
FLOWKS strainers and sight flow indicators protect downstream equipment and provide visual process verification across industrial piping systems. Basket strainers offer open-top screen access for fast debris removal—five-minute maintenance without pipeline disconnection, mesh sizes from coarse pump protection (1/8"–1/2" perforations) to fine instrument and nozzle protection (40–100 mesh wire). Y-type strainers deliver compact high-pressure screening in angled chambers—rated to Class 1500, ideal for steam, compressed air, hydraulic, and small-bore process lines from 1/2" to 12". Dual basket strainers enable continuous-flow straining with a diverter valve switching between two parallel chambers—zero downtime for basket cleaning on critical pump suction and cooling water lines. Duplex basket strainers upgrade the changeover to simultaneous inlet/outlet switching with integral four-port or six-port valve and bleed/vent ports for safe offline maintenance. Temporary cone and flat-plate strainers catch construction debris during commissioning, removed after clean-up cycle. Window-type sight glasses provide borosilicate glass panels for fluid visual inspection—single or dual-window with backlit visibility for dark or opaque media. Flapper and ball-type sight flow indicators add internal motion elements for visual confirmation of flow direction, presence, and relative velocity on small-diameter lines.
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Ball Valves
FLOWKS offers floating ball valve, trunnion mounted ball valve and top entry ball valve for oil & gas, petrochemical and power generation. Designed per API 6D, API 608 and ASME B16.34.
DBB Valves
FLOWKS Double Block & Bleed (DBB) valves provide dual isolation with bleed verification in a single compact body. Replacing traditional multi-valve installations, FLOWKS DBB valves reduce weight, space and potential leak paths. Available in bolted bonnet, all-welded and expanding gate designs per API 6D and API 607.
Gate Valves
FLOWKS gate valves for isolation service in piping systems. Flexible wedge, solid wedge, slab and expanding gate designs per API 600, API 602 and ASME B16.34.
Globe Valves
FLOWKS globe valves for throttling and isolation. Standard, angle, Y-pattern and bellows seal configurations per API 602 and BS 1868.