Accessories & Services
Nautilus Marine Service offeres a broad range of services and accessories to support customization of instrument spheres. Please check out individual model series for details. For the best possible and efficient guidance, Nautilus Marine Service would appreciate it, when a short description/drawing of your application could be provided.

accessoires | overview |
Vacuum pump |
| Deck purge box (pump) that fits vacuum ports, for evacuation of glass housings and to eliminate moisture inside. | |
Vacuum port (self sealing) |
| Titanium vacuum port, selfsealing version with 5mm or 7/16“ threaded bolt. Self-sealing vacuum ports in combination with a Deck Purge Box ease the procedure to open and close pressure housings and eliminate any moisture inside the enclosure. | |
Vacuum port |
| Titanium vacuum port with single and double face seal and 5mm threaded bolt. | |
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 sea water. Scotchrap Tapes have a 5-year shelf life (from date of 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-live 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 is not an option. | |
Hose adapter for vacuum parts |
|
| |
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. | |
Pressure switch |
|
| |
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 housings, by means of o-rings between two flanges. Nautilus Marine Service provides a default flange design and can also manufacture according to customer’s 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 a bonding instruction available as well as corresponding tools and adhesive. Please note: In general, glass housings are very strong against pressure, but do not have the same qualities against tension or shear or torsion. So, do not install glass housings at platforms where they are subjected to such forces. This is particularly important for housings which 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. | |
Lubricant |
| Molykote Lubricant to grease O-rings and connectors before mating. | |
Mounting Ring |
| Mounting rings with or w/o threated inserts which supposed to be fixed (bonded) approx. 25mm below the rim of a corresponding hemisphere. Download Drawing: | |
Bonding Set |
|
| |
Adaptor plates |
| Adapter plates avoid bearing stress for standard connectors. They assure that stress is deducted over a wider area from the connector towards the glass around the edges of the drill hole. | |
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 colour and are neutrally buoyant. Protective shells are offered in 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 swivelling sphere attachment sets is available to support field installations. Protective shells of ribbed design are often used in moorings or application with a large likelihood for impact whereas smooth protective shells 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: Drawing PS-RO_10 , 3D model PS-RO-10 Drawing PS-RO_13 , 3D model PS-RO_13 Drawing PS-RO/RW-17 , 3D model PS-RO/RW-17 Drawing PS-S-17 , 3D model PS-S-17 | |
Mooring system |
| Set of up to five 17” floatation spheres attached to a braided fibre rope (Eddyrope) with swivelling mounting brackets (Eddygrip). | |
Transportation aid |
| xperience has shown that hand carrying heavy glass hemispheres could sometimes be challenging. The proposed lifting aid might be helpful in this regard. |
| Spheres can be made with a variety of through holes to accommodate connectors, feedthroughs, and a vacuum port for connection to electronics and batteries inside, or releases, sensors or other packages on the outside. With the ability to exchange a single hemisphere, one can easily be exchanged by another with a different arrangement of through holes. Through holes can be positioned anywhere across the hemisphere with minimum 30deg away from the edge of the equator. A certain distance between through holes is recommended in order to not weaken the glass at a specific region and to not compromise the integrity of the enclosure. As a rule of thumb, more but smaller holes (diameter < = 5/8”) shall be preferred over few and larger ones. Please note that a completed drill hole specification form (DHS) has to be provided by the buyer latest with the purchase order to specify all interfaces. Usually, each through hole is accompanied by a circular polished spot face (also called ground flat) as a sealing surface. The most common through hole is circular or round with an accuracy of +/- 0.2mm. On demand, the accuracy can be increased to +/- 0.05mm, and other types of through holes can be applied. Please see below for more information. The positioning accuracy (azimuth and elevation) of the through holes is ± 1° and the ground flat’s outer diameter has an accuracy of ± 4 mm. Due to production process and characteristics of glass, the curved surface may not be entirely hemispherical and very small imperfections may appear. Hence, the through holes may need to be re-positioned within the above given specification to ensure a decent round shape of the ground flat and to avoid spalling during the drilling process. Each drill hole is completed by a chamfer with a length of approx. 0.2mm on both ends at approx. 45°. The greatest caution must therefore be exercised in checking tolerances of drill holes and should only be done with measuring gauges of non-metallic material to avoid damages around the chamfers at their the very sensitive edges. If the glass housing will be installed in protective shells and the penetrators protrude more than 5 mm from the spherical surface, we propose to position the through holes under the top of the protective shell. Most space is available 60° referenced to the equator.
| |
| Conical through holes | Conical drill holes (accuracy +/- 0.05mm), conical 1: 10 and 24/29mm | |
Oversized through holes | Oversized (> 5/8", 16.2mm) drill holes (accuracy +/- 0.2mm) and polished spotface | |
High accuracy through holes | 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 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 specification of glass enclosure nor 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 colour); a free circumferential area of approx. 10mm off the equator will remain | |
Paint coating | Paint coating of VITROVEX hemispheres, windows for display of serial number or vacuum monitor may kept out | |
Optical enhancement | Optical enhancement of 13" and 17" hemispheres; due to 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. |



















