Accessories and Services
Customization Options, Mounting Solutions, and Support for Underwater Instrumentation
To support the customization and optimal deployment of VITROVEX® instrument spheres, Nautilus Marine Service offers a comprehensive range of accessories, mounting options, and engineering services. These solutions enable flexible integration with electronic packages, batteries, connectors, sensors, and other underwater instrumentation components.
Through decades of experience, Nautilus ensures that each configuration is tailored to meet the specific requirements of your project, whether for shallow water or full ocean depth applications.
Mounting Flanges & Interface Options
VITROVEX glass spheres can be equipped with mounting flanges made from:
- Titanium (recommended for its compatible thermal expansion coefficient)
- Stainless steel
- Plastic (for short-term, shallow-water use)
These flanges offer an alternative, easy-to-use solution for opening and closing spheres, similar to non-glass enclosures. Leak tightness is achieved through O-ring seals between flanges.
Vacuum Ports, Feedthroughs, & Connector Integration
To enable through-wall connections, VITROVEX® housings can be supplied with:
- Vacuum ports (self-sealing titanium or standard versions)
- Bulkhead connectors and feedthroughs
- Bulkhead adaptor mounting sets (available for circular and low-profile connectors)
These components allow flexible integration with interior electronics or exterior devices such as sensors and releases. Bulkhead adaptors with blanking plugs provide options for unused ports, enabling future expandability.
Note: Instrument spheres are typically opened and closed repeatedly, unlike flotation spheres that are sealed for lifetime use. Drill hole specifications must be confirmed via the Drill Hole Specification (DHS) form.
Protective Solutions & Handling Aids
Protective Shells
- Made from LDPE (low-density polyethylene)
- Available in ribbed (for impact-prone moorings) or smooth (for direct mounting on equipment) designs
- Bright orange color with synthetic fiber padding for shock absorption
- Options to accommodate oversized connectors, view windows, and other modifications
- The EDDYGRIP system is available for swiveling sphere attachments
Transport & Handling Accessories
- Transportation aids for the safe lifting and handling of heavy glass hemispheres
- Mooring systems featuring up to 17″ flotation spheres attached via braided fiber rope with swiveling mounts.
Optical Enhancements & Surface Treatments
- Optical polishing of glass surfaces for high-resolution imaging applications
- Polyurethane coatings (approx. 0.5mm, semi-transparent white) for added surface protection
- Paint coatings with optional view windows for serial numbers or vacuum monitors
Additional Accessories
| Accessory | Description | |
|---|---|---|
| Vacuum Pump / Deck Purge Box |  |
Removes moisture via vacuum evacuation for housings. Download Datasheet: VITROVEX deck purge box |
| Vacuum Port (Self-Sealing) |  |
Titanium vacuum port, self-sealing version with 5mm or 7/16“ threaded bolt. Self-sealing vacuum ports in combination with a Deck Purge Box ease the procedure of opening and closing pressure housings and eliminate any moisture inside the enclosure. Download Datasheet: self-sealing vacuum ports |
| Vacuum Port |  |
Titanium vacuum port with single and double face seal and 5mm threaded bolt. Download Drawing: General arrangement Download Technical notes: Installation guidelines |
| Sealing and Protective Tape |  |
Scotchrap is used to protect the TEROSTAT sealing tape from mechanical damage or from any other negative impact e.g. caused by seawater. Scotchrap Tapes have a 5-year shelf life (from the date of the manufacturer) when stored under the following recommended storage conditions: Store in a clean dry place at a temperature of approx. 21°C (70°F) and 40 to 50% relative humidity. Good stock rotation is recommended.
Shelf life becomes virtually unlimited when stored cool and dry (15°C / 40% rel. humidity). |
| Manometer |  |
Nautilus Marine Service can supply a manometer to quickly check or monitor the status of the vacuum inside the glass housing. The manometer can be bonded anywhere inside the glass enclosure, and a protective shell can be modified with a viewing window in this regard. This feature can be especially useful if a last check of the vacuum is required right before deployment, and time-consuming disassembling efforts of the protective shells are not an option. |
| Hose Adapter for Vacuum Ports |  |
Compatible with vacuum port designs. |
| Heatsink |  |
Filler plug made of Copper requires bulkhead connector ports, approx. heat flow in W @deltaT (40@20°, 60@30°, 80@40°, 100@50°). |
| Pressure Feedthrough |  |
VITROVEX pressure feedthrough (high pressure 1/4″ NPT to 1/16″ NPT), made of stainless steel AISI316. Download Drawing: Pressure feedthrough |
| Pressure Switch |  |
Pressure-activated switch; triggers at approximately 3 bar. |
| Flanges |  |
Flanges provide an alternative solution to open and close spheres. They are often made of Titanium due to similar thermal expansion coefficients. Stainless steel or plastic flanges could also be feasible for short-term deployments or shallow-water applications. Leak tightness is achieved, similar to any other non-glass housing, by means of o-rings between two flanges. Nautilus Marine Service provides a default flange design and can also be manufactured according to customers’ needs.
The glass housing is bonded to the flanges using a commercially available adhesive. For customers who like to apply their own flanges to glass housings, Nautilus Marine Service has bonding instructions available as well as corresponding tools and adhesives. Please note: In general, glass housings are very strong against pressure, but do not have the same qualities against tension shear, or torsion. So, do not install glass housings at platforms where they are subjected to such forces. This is particularly important for housings that have been furnished with metal flanges. Do not use those flanges as mounting support on flexible surfaces. Downloads: Drawing NMS-FLA-Ti-17-I, 3D model (3D) NMS-FLA-Ti-17-I |
| Filler Plugs |  |
Blanking plugs for additional outputs, even if there is no need for all holes at the time of production. |
| Bulkhead Mounting Sets |  |
Bulkhead adaptors offer an additional approach to realize through-wall connections and provide greater flexibility as additional interfaces could be attached proactively and sealed with blanking plugs. Available for circular and low-profile connectors.
Download Datasheet: VITROVEX connector adapter |
| Lubricant |  |
Molykote Lubricant grease O-rings and connectors before mating. |
| Mounting Ring |  |
Mounting rings with or w/o threaded inserts, which are supposed to be fixed (bonded) approx. 25mm below the rim of a corresponding hemisphere. Download Drawing: MR-PVC -7.5 MR-PVC-10 MR-PVC -13 MR-PVC -17 |
| Bonding Set |  |
Bonding Set to attach items to the glass wall. |
| Adaptor plates |  |
Adapter plates avoid bearing stress for standard connectors. They ensure that stress is distributed over a wider area from the connector towards the glass around the edges of the drill hole. Download: technical workshop |
| Protective shells |  Download Technical note: VITROVEX protective shells |
Protective shells for VITROVEX® spherical glass housings are available for impact protection, stowing, and ease of handling. They are made of LDPE (low-density polyethylene) in bright orange color and are neutrally buoyant. Protective shells are offered in a smooth or ribbed design. Each protective shell consists of two flanged halves secured by stainless steel bolts with washers and self-locking nuts. Synthetic fiber pads between the glass sphere and the shell absorb shock and retain the sphere in its position. The number of synthetic fiber pads varies with the sphere model.
Additional mounting hardware, such as Eddygrip/Eddyrope swiveling sphere attachment sets, is available to support field installations. Protective shells of ribbed design are often used in moorings or applications with a large likelihood for impact whereas smooth protective shells are usually used when spheres are mounted directly on underwater equipment such as landers or when the protective shell needs to be modified in order to accommodate (oversized) connectors, transducers, etc. or to provide view holes for cameras, lights, etc. respectively. There is no difference in terms of hydrodynamics or net buoyancy between ribbed and smooth protective shells. Technical drawings for protective shells are available in different formats. Please check our download section. Download: |
| Mooring system |  |
Set of up to five 17” floatation spheres attached to a braided fiber rope (Eddyrope) with swiveling mounting brackets (Eddygrip). |
| Transportation aid |  |
Experience has shown that hand-carrying heavy glass hemispheres could sometimes be challenging. The proposed lifting aid might be helpful in this regard. |
| Drill holes | Drill holes (accuracy +/- 0.2mm) and polished spotface |
| Conical drill holes | Conical drill holes (accuracy +/- 0.05mm), conical 1: 10 and 24/29mm |
| Oversized drill holes | Oversized (> 5/8″, 16.2mm) drill holes (accuracy +/- 0.2mm) and polished spotface |
| High accuracy | High accuracy drill holes (accuracy +/- 0.05mm) and polished spotface |
| Installation of Hydrophone/Transducer | Installation of acoustic transducer (e.g., PET 661G or Benthos TR/XT) |
| Installation of the bulkhead connector | Mounting of bulkhead connectors/vacuum ports incl. provision of corresponding assembly sets (non-default min. shaft length might be required) |
| Pressure test | Pressure tests, test value has to be specified and MUST NOT exceed the specification of the glass enclosure or the 3rd party equipment |
| Bonding | Bonding of non-glass items such as flanges, mounting rings, etc., to VITROVEX glass articles |
| Polyurethane coating | Polyurethane coating of VITROVEX hemispheres (approx. 0.5mm width, semi-transparent white color); a free circumferential area of approx. 10mm off the equator will remain |
| Paint coating | Paint coating of VITROVEX hemispheres, windows for display of the serial number, or a vacuum monitor may be kept out |
| Optical enhancement | Optical enhancement of 13″ and 17″ hemispheres; due to the production process and characteristics of glass, small bubbles, and other impurities may remain |
| Shell modification | Modification of protective shells |
| Engineering | Assistance and consulting services to turn customer-specific requirements into high-quality pressure vessels. |
Custom Services & Engineering Support
Nautilus Marine Service provides a range of services to support product customization and ensure optimal system performance:
- Pressure testing (performed within specified housing and equipment ratings)
- Drill hole configurations (including conical, oversized, or high-precision holes)
- Installation of bulkhead connectors, vacuum ports, and acoustic transducers
- Bonding of flanges, rings, and non-glass items to VITROVEX® enclosures
- Protective shell modifications for specialized applications.
- Engineering consultation to translate project requirements into reliable, high-quality pressure vessels
Configuration Guidance
Before selecting your VITROVEX® glass enclosure, consider the following:
- Maximum Depth Rating
- Required Buoyancy (refer to the Floatation Spheres section for positive buoyancy solutions)
- Inner diameter to fit built-in equipment
- Type of protective shell (ribbed or smooth)
- Need for pressure testing or optical enhancement
Please complete the Drill Hole Specification (DHS) form prior to submitting your inquiry to ensure alignment with your project needs. The form is available in the Downloads section.
