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THE PREMIER FULL-RANGE SIGHT GLASS MANUFACTURER

Available at Alpha Process Sales - All Locations & Murray Engineering - Northern Texas

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Pressure Products Company (PPC) is a pioneer in the safety sight glass industry, producing a complete line of sight glasses, liquid level gauges, sight flow indicators, process lights, reactors/chambers, ultrasonic stencil cleaners, and concentration monitoring systems. 

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PPC'S FEATURED PRODUCT

SIGHT GLASS

The Hinged Closure Sight Glass provides convenient access to the process without the need to fully disassemble and re-assemble a unit.

The hinged closure unit is designed for a weld pad or flange connection (ANSI, DIN, or special bolt pattern) and for mounting our Model B or Model L units (depending on pressure requirements) to be hinged and sealed on an O-ring or gasket. A variety of materials of construction are available to meet your process needs.

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Features & Benefits

This sight glass has been certified as maintaining a Quality Assurance System in accordance with the Pressure Equipment Directive 97/23/EC (PED) Annex I, Paragraph 4.3 by the Certification Body 0036 of the TÜV Industrie Service GmbH.

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STANDARD SIGHT GLASSES

Sight glasses allow direct visual observation of processes within industrial pipes, tanks, and vessels. Most competing units consist of a piece of glass sandwiched between two metal flanges. By contrast, our sight windows are designed to circumvent the significant limitations of such designs, and provide the users with an easily maintained installation that offer large margins of safety. Custom safety sight glasses can be designed to meet your exact specifications.
The majority of our units are Factory Mutual approved. The following standard models are available for immediate ordering at (800) 624-9043 (click on any listing for a product description, engineering details, materials of construction, and unit image).
Model L Flange Sight Glass

​Simple, safe and economical are the hallmarks of the Model L Flange sight glass from Pressure Products. The Model L features a better seal and lower maintenance needs than competing sight glasses. Rated for temperatures up to 405°F and pressures ranging from full vacuum to 100psi, the Model L is an ideal choice for lower-pressure applications using standard 150psi ANSI B16.5 (2" to 8") flange mounts. The Model L is designed so that none of its metal parts (either carbon steel or stainless steel) are in contact with the process fluid, and no mating gaskets are required.

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Model S Flange Sight Glass

​​The Model S combines the lowest cost on the market with the ease of installation associated with our premium models.

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Model L Weld Sight Glass

​Low cost, maintenance friendly L weld sight glasses feature larger viewing window diameters than ANSI flanges of comparable overall sizes. This design features our proprietary glass sidewall sealing mechanism that provides the following advantages: 

Larger view for the given size of weld body compared to ANSI flange diameters.

Lower cost for a given window size due to the smaller body size.

Easy maintenance - It is impossible to crush the glass window by over-torqueing the flange bolts

Excellent sealingThe proprietary sidewall seal will hold through many thermal cycles and
pressure cycles

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X150 Sight Glass

L​arge pressure safety margins from extra-thick lens: The single, thick lens of the X150 is capable of withstanding pressure overshoots. Easy and Safe Maintenance: Maintenance introduces a major failure risk for conventional sight glasses, and plastic sealing gaskets eventually develop leaks. In many cases, additional sealing stress is applied to the gaskets as a resort. With a conventional sight glass, this additional stress is applied to the face of the glass lens. This can result in a catastrophic failure if the glass is eventually crushed.

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Model B Flange Sight Glass

The Model B Flange unit with threaded lens retainer cap mounts on standard ANSI B16.5 (2" to 24") flange accommodations. Units can be manufactured to meet your pressure and temperature requirements, and different materials of construction are available

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Model B Weld Sight Glass

The Model B Weld unit with threaded lens retainer cap mounts on standard ANSI B16.5 (2" to 24") weld accommodations, and is designed to become an integral part of a vessel shell, vessel head, manway cover or pipeline.

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Model I Flange Sight Glass

If corrosion resistance is only needed on wetted parts of a sight glass, our Model I Flange sight glass unit is an ideal choice for the application.

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Model I Slip-On Flange Sight Glass

The Model I slip-on unit is a solution for deeply recessed or unusually sized connections. The Slip-On model allows fitting in deeply recessed or unusually-sized connections.

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Model I Weld Sight Glass

The Model I's insert can be made from a wide variety of materials (stainless steel, glass-lined, or Hastelloy, etc) to ensure compatibility with any process fluid, while the main unit body can be made of carbon steel (or any material your application requires). As with all PPC products, the Model I Weld can be made to meet any pressure and temperature requirements.

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Model A Flange Sight Glass

The Model A Flange unit mounts on standard ANSI B16.5 (2" to 8") flange accommodations, and can be manufactured to meet a wide range of pressure and temperature requirements.

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Oblong Sight Glass

Oblong Sight Glass units are used where increase the viewing lengths beyond that of standard sight glasses are required. Our oblong units are designed for pressures up to 150psi and temperatures up to 450°F, and various materials of construction are available to meet your process needs.

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Bulls Eye Sight Glass

Threaded-connection Bulls Eye sight glass units offer the highest pressure and temperature service of any sight glasses.

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Hinged Closure Sight Glass

Provides convenient access to the process without the need to fully disassemble and re-assemble a unit.

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STANDARD SIGHT GLASSES

SIGHT FLOW INDICATORS

Sight flow indicators are inline piping-based units that allow direct observation of material flow through a line. These typically consist of two circular sight glasses positioned 90 degrees to the direction of the flow and 180 degrees from one another. All of our sight flow indicators benefit from the advantages of our sight glass designs, namely the ease of sealing, maintenance, and availability in higher pressure/temperature combinations in larger sizes than any other manufacturer in the industry. Since fluid flow is always driven by pressure, ease and robustness of sealing is even more important than in plain sight-window applications. Our unique radial sealing of the glass decouples the sealing stresses from the process pressure, and enables higher sealing stresses to be applied without endangering the glass--which in turn enables higher pressures to be maintained.
Model L Safesite Sight Flow Indicator

​An inline (see-thru) type of sight flow indicator assembly using standard Model L sight glasses.

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Model B Safesite Sight Flow Indicator

​​The Model B SafeSite is an inline (see-thru) type of sight flow indicator assembly that allows the observation of material flow through a line.

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Model I Safesite Sight Flow Indicator

​An inline (see-thru) type of sight flow indicator assembly using standard Model I sight glasses.

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Full View Sight Flow Indicator

The Full View sight flow indicator is an in-line (see-thru) type of sight flow indicator that is used to provide 360-degree viewing of material flow through a line.

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Bull's Eye Sight Flow Indicator

An inline (see-thru) type of high-pressure flow indicator assembly using standard Bull's Eye sight glasses.

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Duraport Sanitary See-Thru Fused Sight Glass

Fused sight glasses mounted to a sanitary short-stack cross. This unit allows the user to easily distinguish flow in the line as well as color or clarity of the material. The sanitary clamp design allows the unit to be quickly removed without tools for easy cleaning.

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Duraport Threaded See-Thru Fused Sight Glass

DuraPort Threaded See-Thru Sight Flow Indicator is designed for smaller pipelines with connections of 1/4" to 11/2" The DuraPort lenses will allow the user to easily distinguish flow in the line as well as color or clarity of the material.

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SIGHT FLOW INDICATORS

LIQUID LEVEL GAUGES

Liquid level gauges have the distinction of being the safest in the industry. An experienced plant operator is familiar with the direct relationship between the ease of resealing a leaky level gauge and enhanced safety in the handling of flammable, corrosive, or otherwise hazardous materials. Our complete line of liquid level gauges feature our unique peripheral sealing scheme, which decouples sealing stresses from the process pressure. This enables our level gauges to meet higher temperature and pressure requirements than competing designs. As a result, our level gauges are more forgiving of imperfect screw torqueing by operators, and permit rapid resealing of leaks without gasket replacements.
Standard Liquid Level Gauges

Model Q2 -  industry standard design for general monitoring of liquid levels industrial processes and tanks.

Model Q3 - industry standard design for general monitoring of liquid levels industrial processes and tanks for high pressure applications

Liquid Level Gauge Valves

​​Many different valve types are available for use with our liquid level gauges, including ball valves, gauge valves and needle valves.

See Thru Liquid Level Gauge

​A two-sided level gauge that allows light to pass through for easier viewing.

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Reflex Liquid Level Gauge

A basic type of level gauge that offers a lower initial cost. The Reflex Liquid Level gauge allows visual observation of level, color, or clarity of a liquid in a vessel or tank at a low initial cost.

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Weld Pad Liquid Level Gauge

The Weld Pad Liquid Level gauge is designed to be welded directly onto a tank or other liquid-containing vessel, and allows visual observation of level, color, or clarity of a liquid in a vessel or tank at a low initial cost.

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Tubular Liquid Level Gauge

Tubular Level Gauges are designed to view liquid levels using clear or red line Borosilicate (Pyrex) tubing to view liquid levels. All valves use a stuffing box configuration to seal the glass tube, and have a ball check shutoff to prevent loss of vessel contents in case of glass failure. Operating pressure and temperatures are subject to the limitations of the tubular gauge glass and washer composition.

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LIQUID LEVEL GAUGES

PROCESS LIGHTS

PresSure Products Company offers a complete line of solutions for any industrial process lighting need. Explosion proof process lights are suitable for illumination of processes in hazardous locations where combustible gases or vapors might be present. High intensity discharge (HID) explosion proof process lights are the brightest in the industry, able to illuminate the largest tanks or processes. They are designed to transmit light efficiently through the small diameter of a sight glass. Fiber optic process lighting solutions offer flexibility for awkward light mounting requirements. Various options for mounting process illumination lights onto sight glasses are available, and custom options can be provided as needed.
Explosion Proof Model 2376 Light

​The 2376 is an explosion-proof light for illuminating the insides of tanks or process vessels, general lighting in chemical plants and petrochemical plants, and in suspension over tank portholes.

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Explosion Proof Model EVTL Light

​​The EVTL includes two styles of explosion-proof lights to be used for spotlighting the insides of tanks or process vessels, general lighting in chemical plants and petrochemical plants, and for porthole or sight glass applications.

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Explosion Proof Model HKB Light

The HKB is an explosion-proof light used for spotlighting the insides of tanks or process vessels; for general lighting in chemical plants and petrochemical plants; and for porthole or sight glass applications.

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Model R50 Light

The hallmark of our Model R50 process light its ability to be mounted via a variety of sanitary couplings. The face plate of the R50 is a fused-glass sanitary DuraPort sight window which is capable of direct connection to the process vessel. All light sources can operate continuously, without the need for shutoff timers or thermal cutoffs. Available lamps include 20-, 35-, and 50-watt units operating at either 12 or 120 volts. Each lamp is self-contained, with a built-in reflector.

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Model T50 Light

The face plates of the T50s are special fused-glass sanitary DuraPorts capable of direct connection to the process vessel. All light sources can operate continuously, without the need for shutoff timers or thermal cutoffs. Available lamps include 20-, 35-, and 50-watt units operating at either 12 or 120 volts, and are self-contained, with a built-in reflector.

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BC75 & BC150 Fiber Optic Process Light

 BC fiber optic light family is comprised of two physically identical units that are assembled from purchased heat-sink extrusions and certain fabricated body parts. There are two models, the BC75, with a 75-watt halogen lamp; and the BC150, with a 150-watt halogen lamp. These models are designed to employ fiber optic cables of various lengths to . Because of the thermal design, both units are capable of continuous operation, with no thermal cutoffs or timers required

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LED Process Lights

LED process lighting consists of three different types (Head, Ring or Strip). The LED lights are used for backlighting of sight flow indicators or liquid level gauges.

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PROCESS LIGHTS

SIGHT GLASS ACCESSORIES

Wiper Assembly for Sight Glasses

​Wiper Assembly satisfies the need to clean the lens on the process side of the sight glass without disassembly of the unit.

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Spray Rings for Sight Glasses

​​Spray rings allow the inside of the glass to be washed clean without disassembling the unit.

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Weld Pads for Sight Glasses

Weld pads are designed to be welded directly to the vessel. Designed for welding to new or existing equipment to become an integral part of a vessel wall, vessel head, manway cover or in a pipeline system. It is available with the weldment contoured to fit a specific radius (cylindrical or spherical).

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Purge Rings for Sight Glasses

The Purge Ring is designed to fit between standard ANSI B16.5 flange, DIN standards or non-ANSI connections. It is used to purge the line with air, water or any other media.

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SIGHT GLASS ACCESSORIES

SIGHT GLASS PARTS & HARDWARE

Sight Glass and Level Gauge Lenses

Circular Glass - ​Standard sight glass units, flow indicators and bull's eye sight glasses. Standard annular edge glasses also available.

Level Gauge Glass - Standard flat gauge glasses are available in Reflex and High Pressure/Transparent types from size 1 to size 9.

Oblong Glass - Designed for oblong sight glass units

Full View Tubular Glass - Tubular glass for full view sight flow indicators.

Beveled Glass - Designed for specialty sight glass assemblies

Gaskets for Sight Glasses

​​Gaskets are used with sight glasses, level gauges and sight flow indicators for cushioning/sealing the lens(es) or as a mating gasket between flanges. A wide variety of gasket types and materials are available to meet any process need.

Lens Packing for Sight Glasses

Lens packing is used to provide sealing stress against the glass lens of a sight glass unit.

Cap Screws for Sight Glasses

Cap screws are used to secure the retainer caps of weld-unit sight glasses, level gauges and sight flow indicators.

Compression Screws for Sight Glasses

Compression screws are used to apply sealing stress to the lens packing on certain sight glass, sight flow indicator and liquid level gauge models via a compression ring.

Compression Rings for Sight Glasses

Compression rings are components of certain sight glass, sight flow indicator models, and are used to apply sealing stress to the unit's lens packing.

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PARTS & HARDWARE

INSTRUMENTATION & PROCESS CONTROL

Pressure Gauges

Model 550: The Model 550 gauge can be used in dry or liquid process fluid environments. This unit mounts via a standard NPT connection.

Model 1900: The Model 1900 gauge can be used in dry or liquid process fluid environments. This unit mounts via a standard NPT connection available in a variety of metal materials.

Model 100: The Model 100 gauge can be used in dry or liquid process fluid environments. This unit mounts via a standard stainless steel NPT connection.

Temperature Sensors

Designed to be attached to vessels, pipes or sight glass, sight flow indicator or liquid level gauge unit bodies, and offer precision accuracy.​​

Pressure Sensors

Designed to be attached to vessels, pipes or sight glass, sight flow indicator or liquid level gauge unit bodies, and offer precision accuracy.

Bi-Metal Thermometers & Thermowells

Thermometers are designed to be attached to vessels, pipes or sight glass, sight flow indicator or liquid level gauge unit bodies, and offer precision accuracy.

Thermowells are recommended whenever the process being measured may be under pressure, is corrosive, is abrasive, or is moving at a high velocity.

Proximity Switches & Compact Level Sensors

Proximity Switches and Compact Level Sensors are designed to be attached to vessels, pipes or sight glass, sight flow indicator or liquid level gauge unit bodies.

Diaphragm Seals & Snubbers

Diaphragm Seals isolate the measuring element of an instrument from the pressure media. Applications include corrosives, slurries, highly viscous processes, paint, and pulp.

Piston Type Snubbers are effective on those applications that require additional in-line snubbing. Unlike sintered metal snubbers, Piston Type Snubbers resist clogging and are self-cleaning. Five different sized pistons are included with each Snubber to insure the correct amount of snubbing for virtually every application.

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INSTRUMENTATION & PROCESS CONTROL

RESEARCH REACTORS & CHAMBERS

Research Reactors and Chambers

Custom-designed vessels, including suction line accumulators, mixing chambers, and fuel injection testers, can be manufactured with various types of circular sight glasses or level gauges for monitoring and viewing contents. Vessel design specifications such as size, materials of construction, pressure, temperature, etc. are determined by individual customer applications.

Vessels are available from simple bench-scale to more complex systems. Accessories include heaters, pressure and temperature gauges, valves, instrumentation, wheels/carts, pumps, etc.; choice of connection includes NPT, flange, sanitary, and more. Vessels made of stainless steel, carbon steel, or exotic alloys are available, and have been manufactured for various industries, research facilities, laboratories, government, and universities.

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RESEARCH REACTORS & CHAMBER

MANWAYS

Manways

T-Bolt Hinge Closures are used as manways for access to storage tanks, mixing vessels, separators and other batch equipment. The closure consists of a thick semi-ellipsoidal head that is hinged to a matching hub, o-ring and a suitable number of T-Bolts to effect and maintain a tight seal. 

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MANWAYS
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