Our method for lens retention virtually eliminates stress concentration introduced into the glass lens assembly when bolting the sight glass into its service position. The Cyclops Industries, Inc. laminated lens assembly is encapsulated and bonded into a lens ferrule; forming an integral one piece ferrule assembly. This one piece ferrule assembly absorbs the bolting stresses instead of subjecting the glass lens to the stress concentrations. This patented retaining method, together with the multi-layered lens, usually a three (3) piece assembly is your assurance of complete sight glass integrity and safety.

Quality Control

Each lens assembly carries a double safety factor of 10 and usually consists of there (3) pieces of fully tempered glass discs which are laminated in a jig to insure a uniform thickness and diameter. They are then bonded into a lens ferrule. The laminating and potting procedures are a time/temperature curing process performed in a controlled atmosphere. All fabricated parts are machined to tolerance so ASME approved plus or minus 0.0025 inch and are made from high quality ASME approved materials.

weld mounted sight glasses

Complete mill test reports are supplied with each weld type unit as standard practice. Generally speaking each of our weld mounted sight glasses are self-reinforcing to the vessel shell However, it is recommended that reinforcement calculations on all ASME code constructed vessels be carefully checked to insure proper reinforcement of the vessel wall. Precision boring the gasket surface of a 24" forged steel flange, one of the 35 largest lens assemblies fabricated to date by Cyclops Industries, Inc.

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Reconditioned Lens Ferrule

  • A lens holder assembly returned to Cyclops Industries for reconditioning will have all of the glass and gasketing removed from the metal lens ferrule and discarded.
  • The lens ferrule itself will be cleaned, and checked for any damage to gasket surfaces and distortion in any manner. Any reconditioning to machine surfaces that is required is performed. All new glass and gasketing is then installed into the ferrule in the same manner as newly manufactured units.
  • Tractability of your metal ferrule is assured by serial number which is etched into the side of the metal ferrule and permanent record is maintained. Also when received at Cyclops the item is tagged with the assigned shop work order number and company name.

A reconditioned lens ferrule assembly meets all of the tolerance and quality assurance criteria as applies to newly manufactured units.

Simplified 2-Piece Installation

Simplified 2-Piece Installation
  • Standard Cyclops Safety Sight Glasses are available in flanged or weld mounted designs as well as in-line sight flow indicators, which can be supplied with either welded, threaded or flanged connection; all are available in 1 inch through 8 inch - 150 lb., 300 lb. and 600 lb. units and are rated for 450 deg. F.
  • Special units can be designed on request.

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Laminated Lens Assembly & Mounting

laminated lens assembly and mounting

Guarantees Greater Safety - Eliminates Costly Failures

The Lens Assembly:

No other sight glass offers this multiple safety factor - three glass disks laminated into a single lens assembly:

  • Two tempered pressure disks are designed for full-rated working pressure. Even if one should fail, the other will still hold the pressure.
  • Together with a bottom disk of chemical-resistant glass to shield against corrosion, Cyclops glasses assure maximum performance at maximum safety.

The Lens Ferrule:

By fusing the lens assembly to the lip of the ferrule with a Teflon' gasket, and bonding to the inside of the ferrule with a strong, resilient, heat and chemical-resistant compound, the lens assembly and lens ferrule are made into a single unstressed unit.

The Mounting:

The single unit is mounted with a hold-down flange and a high quality cushion gasket which provides for an extremely compact mooting assembly.

Through this simplified one-step procedure, it is impossible for a competent mechanic to improperly install Cyclops Safety Sight Glasses.

Cyclops Safety Sight Glasses:

  • Can be installed on new or present equipment for all liquid and vapor service
  • Require no packing or maintenance
  • Are easy to replace
  • Reduce down-time to an absolute minimum
  • Are helium leak tested/very low leakage rates

Approved by Factory Mutual:

Cyclops Safety Sight Glasses have been tested and approved for use at their rated working pressures and temperatures by the Factory Mutual Engineering Corporation of Norwood, Massachusetts

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