Instructional Guide
(Inspection, Installation, Etc.)
Safety First!
Please read this document carefully to fully understand the best methods for safety, installation, handling and keeping your warranties valid.
SAFETY
Rayotek Sight Window Products are fabricated and tested to exceed industry standards. As dependable as Rayotek Sight Window Products are, pressure and vacuum systems are inherently dangerous and thus proper caution must be practiced when using Sight Windows. If not installed and/or used properly Sight Windows can be dangerous.
Suggested Precautions:
INSPECTION & CARE
HANDLING:
Rayotek Sight Windows are designed and manufactured to be robust and reliable once they are installed into the system for which they are designed. Prior to installation Rayotek Sight Windows must be handled properly to avoid damage.
Sight Windows should be handled in a manner to avoid any contact with hard objects. Even if the metal Housing of a Sight Window is impacted it could compromise the Sight Window integrity and render it unsafe.
For example, dropping a Sight Window onto a hard floor could shock the Window material and cause an incidental crack that is not visible to the naked eye. Even though invisible, the Sight Window may be compromised and could fail when exposed to pressures.
Good handling practices should also be observed during installation.
CLEANING:
Rayotek Sight Windows should be cleaned the same way you would clean optical glass to avoid scratching:
If unsure on the best way to clean your Sight Window(s), please contact Rayotek for more information.
INSPECTION:
All Rayotek Sight Window Products are inspected and pressure tested* at the Rayotek facility prior to packaging. Damage during shipping could occur, therefore, upon receiving your Rayotek Sight Window(s), please inspect thoroughly:
If you have concerns after inspecting a Rayotek Sight Window contact Rayotek immediately!
Never use a Rayotek Sight Window if there is visible damage to the Window material; when under pressure the Window could fail!
*For larger volumes an adequate sampling may be pressure tested in lieu of the entire lot.
STORAGE:
Store Rayotek Sight Window Products in the box they were received in or an equivalent packaging system that will not allow the Sight Windows to come in contact with each other or any other hard objects.
Sight Windows should be stored and sealed so they do not collect dust and dirt. Some Sight Window materials such as ZeSe are very soft and will scratch easily when contaminated.
INSTALLATION:
WARNING: NEVER SEAL TO THE ACTUAL WINDOW MATERIAL, ONLY THE METAL HOUSING.
Click below to go directly to installation method for your design:NPT INSTALLATION
NPT Tools
Rayotek NPT Sight Windows are designed to be tightened with symmetric loads.
Use only the following types of wrenches:
Using any other type of tool will void the warranty and risk damage to the Sight Window.
Do Not Use:
Using these prohibited tools can damage your Sight Window and will void the warranty.
NPT Tightening:
All Rayotek NPT Sight Windows should be tightened as follows:
NPT FITTING SIZE (inches) |
MAXIMUM TURNS PAST FINGER TIGHT |
MAX TORQUE |
1/4 |
2.5 |
15 |
3/8 |
2.5 |
15 |
1/2 |
3.0 |
50 |
3/4 |
3.0 |
75 |
1 |
3.0 |
110 |
1 -1/4 |
3.0 |
横山美雪150 |
1- 1/2 |
3.0 |
210 |
2 |
3.0 |
260 |
2 -1/2 |
3.0 |
300 |
3 |
3.0 |
350 |
4 |
3.0 |
400 |
Over tightening can damage the Sight Window and will void the warranty.
SAE INSTALLATION
SAE Tools
Rayotek SAE Sight Windows are designed to be tightened with symmetric loads.
Use only the following types of wrenches:
Using any other type of tool will void the warranty and risk damaging the Sight Windows.
Do not to use:
Using these prohibited tools can damage your Sight Window and will void the warranty.
SAE Tightening:
All Rayotek SAE Sight Windows should be tightened as follows:
SAE SIZE (dash #) |
ASSOCIATED TUBE SIZE |
MAX TORQUE |
-4 |
1/4 |
14 |
-6 |
3/8 |
24 |
-8 |
1/2 |
42 |
-12 |
3/4 |
75 |
-16 |
1 |
120 |
-20 |
1 1/4 |
横山美雪 160 |
-24 |
1 1/2 |
165 |
-32 |
2 |
240 |
Over tightening can damage the Sight Window and will void the warranty.
BOLTED FLANGE INSTALLATION
WARNING:
CF, ISO, ASME, Furnace & Incinerator Windows, Custom Bolted Flanges
- Review all order & shipment documentation for application specific instructions and any additional information.
- Inspect & Clean: inspect the flange to make sure all sealing surfaces are clean and that there are no scratches that could compromise the seal. Clean if necessary.
- Seal Material (o-ring, gasket, etc.): make sure the seal is clean, new and with no cracks or damage. Always use a fresh, clean seal.
- Liquid Seals: apply liquid/paste seal (where applicable) to clean surfaces with clean applicator. Do not use wooden or paper applicators; they may contaminate liquid seals.
- Lubricate Threads: use proper lubricant on male and female threads and washer. Torque readings will be incorrect if the bolts are not properly lubricated.
- Position Flange: set in position on mating surface. If a liquid or paste seal is used, be careful not to smear the seal.
- Secure Flange: if the Sight Window is to be installed in a position where it could fall, (such as vertically) use a second set of hands or clamps to support the Sight Window while securing the bolts. If the Sight Window were to drop or swing into a hard surface it could be damaged.
- Hand Tighten: hand tighten using the proper bolt tightening pattern (see below for examples). Repeat bolt-tightening pattern until bolts will not hand tighten more.
- Clamping System Removal: remove any clamping system before fully tightening the bolts.
- Wrench Tighten:
A. Before wrench tightening, determine the appropriate torqueing pattern to minimize flexing of the Flanged Sight Window.
Some examples:
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B. Gradually torque the bolts, using the proper torqueing pattern, as follows:
- Snug up the bolts to less than 5% of the maximum torque value.
- Tighten the bolts to 25% of the maximum torque value.
- Tighten the bolts to 50% of the maximum torque value.
- Tighten the bolts to 75% of the maximum torque value.
- Tighten the bolts to 100% of the maximum torque value.
- Continue to tighten the bolts until they do not move at 100% of the torque value.
- You may need to re-tighten the bolts to 100% of the torque value after 24 hours once the bolts have seated.
Unlike a typical ASME/ANSI flange, Sight Window equipped flanges are typically used as the end of a pipe run and therefore do not carry a large load or stress. Thus, the ASME/ANSI specification for flange connections is generally far higher than torque requirements for sealing Sight Window equipped flanges.
Rayotek supplies order & shipping documentation with all ASME/ANSI and flange style sight windows listing the appropriate torque values based on a predetermined gasket style. Always follow application specific torque values for safe sealing.
If you cannot find the correct torque values please contact Rayotek for assistance.
Custom Rayotek Sight Window Installation:
Rayotek Custom Sight Window Systems that do not fall under one of the above configurations (threaded or flanged) fall under two categories:
- Rayotek Design: Please contact Rayotek for assistance.
- Customer Design: For Customer Designed Sight Window Products the customer is responsible for proper installation. If there are concerns that the installation procedures are incorrect or inadequate please feel free to contact Rayotek for assistance.
WARRANTY & DISCLAIMERS
Responsibilities:
Customer assumes full responsibility for the safe and competent installation and use (within specifications) of any Sight Window manufactured by Rayotek. Any injury, damage or loss resulting from improper installation or use is the sole responsibility of the customer.
- Rayotek Engineered Sight Windows - Rayotek warrants that all Rayotek Engineered Sight Windows are designed and manufactured within the specifications stated by Rayotek. Rayotek warrants for one (1) year from date of shipment to customer that all Rayotek Engineered Sight Windows will function reliably and safely as long as they are properly installed and used within Rayotek's specifications. Specifications and test data are available upon request. See Terms and Conditions横山美雪 for warranty and liability details.
- Customer Designed & Engineered Sight Windows – Rayotek warrants for one (1) year from date of shipment to customer that all Customer Designed and Engineered Sight Windows are manufactured to the customer's specifications. Customer takes full responsibility for any failure, injury, damage or loss that occurs as a result of Customer's Design, engineering, installation and use. Any modification to a Customer Design recommended by Rayotek must be: 1) approved by the customer in writing (or by customer's drawing revision) and 2) customer assumes full responsibility of the final product as a design solely originating from the customer. See Terms and Conditions for warranty and liability details.
- Modifications, Changes or Damage to Rayotek Sight Windows - Any modification, change or damage to a Rayotek Sight Window could result in an unsafe Sight Window and will void all warranties for the Sight Window(s). Customer takes full responsibility for any failure, injury, damage or loss that occurs as a result of the use of a modified or damaged Rayotek Sight Window Product. If a Rayotek Sight Window Product is found to be damaged it should be immediately removed from service to avoid failure. See Terms and Conditions for warranty and liability details.
Customer assumes full responsibility for the safe and competent installation and use (within specifications)
of any Sight Window manufactured by Rayotek. Any injury, damage or loss resulting from
improper installation or use is the sole responsibility of the customer.
Thank you for the safe and productive use of
Rayotek Sight Window Products!!
Please contact us with any questions or concerns