For convenience, we’ve broken our FAQs into subheadings:
A: We have heard customers recommend hot aqua-regia, cold aqua-regia, baking or other cleaning regimens. In general, however, Precision Glassblowing recommends that torches not be cleaned. As odd as it may seem, the constant strain of temperature changes and solvents used for cleaning actually shorten the life-span of a torch. There are, of course, exceptions. For more information, talk to your sales representative.
A: The A-type nebulizer was the original concentric nebulizer developed, and has an internal capillary ground flush to the nose. The technology has since evolved into a C-type neb. which has an internal capillary slightly recessed with regard to the nose resulting in a higher tolerance for dissolved solids and a more consistent aerosol making it much preferred over the older A-Type. Sometime after this, there was a push to consume less argon and so the K-type neb. was developed which functions much like a C-type but uses only 0.7 liter/minute of argon as opposed to the 1 liter/minute of argon the C-types use.
A: Simply put, an axial torch is one used in an instrument arranged in an axial, or horizontal, orientation. A radial torch is used in a vertical orientation.
A: Precision Glassblowing strives to maintain stock on all common ICP and ICP/MS consumables. Custom and back ordered items usually carry a 2-4 week turn-around-time assuming raw materials are in stock. On occasion, the availability of raw materials may require longer lead times.
A: Order expediting is available in most cases for an additional fee. Please contact your sales representative for more details.
1. Q: Do you offer AR coated windows?
A: Yes, we can offer double-side AR coated windows on any cell made from quartz with quartz or fused silica windows. We stock windows AR coated for 780-795 nm but we can offer most any AR coating although charges for a custom coating batch may apply.
A: Due to the coefficient of thermal expansion of Pyrex and heat required to attach the windows, at this time we are not able to offer double-side AR coated windows. AR coating can be applied to the outside surfaces of the windows once cells are constructed but the cost may be prohibitive for a small quantity of cells.
A: Due to the difference on coefficient of expansion, quartz or fused silica windows cannot be attached to a Pyrex cell body.
A: Alkali metal vapor begins to react with Pyrex and quartz/fused silica in excess of 110-120C, although the reaction with Pyrex is slower. The higher the temperature, the faster the reaction until all alkali metal is consumed and no vapor exists to generate a signal. Standard vapor cells should be operated at no higher than 110C to ensure a long useful lifetime.
A: Paraffin inside cells breaks down with too much heat. We recommend a maximum working temperature of 80C for cells with paraffin coating. OTS coating can withstand much higher temperatures up to 200C. However, please note prolonged contact between alkali vapor and OTS coating will cause the OTS to break down. Thus, we advise customers to collect the alkali material into the cold finger at the center of the cell (fill stem) when the cells are not in use.
A: At this time, the process of fusing Pyrex windows to a Pyrex cell body makes attachment of wedged windows very difficult and can cause a high level of distortion and damage to the clear aperture of the windows. However, we can attach Pyrex windows at an angle with no issue.
A: The process of placing alkali metal vapor into a cell is done on a manifold under vacuum through a glass fill stem. The cells are then closed leaving a small tip off. Because the resulting tip off can vary with each cell there is no accurate way to tare or weigh the cells prior to filling and determine a quantity of metal inside each cell. We estimate 5-10 mg of alkali material per cell. A “heavy” fill or large quantity of alkali material can be placed inside the cell upon request. Additional charges may apply for isotopically enriched materials.
A: Yes, every cell we produce is He leak checked down to 1E-9 CC/sec.
1. Q: Do you offer internal and external AR coating?
A: For our quartz octagonal and quartz 6-way cross designs, we can offer double side AR coating on all window surfaces. For rectangular cells, we have previously offer external AR coating but with such a difficult geometry, AR coating is only marginally successful. Internal AR coating to an enclosed area is not possible due to the deposition process.
A: We offer cells with sources made using SAES alkali metal dispensers (AMDs). Rb sources are the most common but we also offer Cs, K and Na upon request.
A: A typical single source contains 2 or 3 SAES AMDs plus a common wire.
A: We advise sending current to only one AMD at a time. Operating more than one dispenser within the same source is likely to burn up the common wire leading to a non-functioning source and potentially creating a leak at the feedthrough.
A: The recommended maximum temperature is 250C limited by the glass to metal seal. A temperature ramp up of 2 C/min is a safe rate.
1. Q: What is Devitrification?
A: Technically, glass is an amorphous solid, existing in a state of imbalance. Devitrification occurs when the glass molecules begin to order themselves into a crystalline structure, causing the glass to become more brittle and develop a cloudy-white appearance. For more information on devitrification, click here.
A: Pyrex is actually a trade name for Corning borosilicate glass, but is commonly used synonymously to refer to any borosilicate glass. Borosilicate is a silicate glass with boron in it. It has a very low coefficient of expansion compared to other glass. Quartz glass is a highly pure silicate glass with a coefficient of expansion even lower than borosilicate glass and an even higher melting point.
A: Borosilicate glass has a melting point around 820oC (1,508oF) and is annealed around 550oC (1,022oF). Quartz glass begins to melt around 1,665oC (3,029oF) and is usually annealed around 1,140oC (2,084oF).
1. Q: Does Precision Glassblowing repair ICP, ICP-MS, and general laboratory glassware?
A: Yes! We excel in repairing ICP and ICP/MS glassware, and can also repair almost any quartz or borosilicate laboratory glassware. Please refer to our Repairs Page for more information and a copy of our repair form.
A: No. Precision Glassblowing works solely with Quartz and Borosilicate glass. Crystal and artistically blown soft glass pieces are not our specialty.
A: No. All we ask is that you include a completed repair form. We will contact you once we’ve received the part or parts and evaluated them for repair.
A: Due to the magnitude of repair items we receive, repairs carry a 4-5 week turn-around-time.
A: Order expediting is sometimes available for an additional fee. Please contact your sales representative for more details.