Unique silicone based system for sealing leaks in high and ultra high vacuum systems

独特的硅酮基系统，用于密封高真空及超高真空系统中的泄漏

Products  产品
Vacseal® High Vacuum Leak Sealant, Aerosol		Vacseal®   High Vacuum Leak Sealant, Liquid
Products	Model	Products	Model
16 oz Aerosol can	VSQ-16OZ	0.5oz Bottle with brush applicator	VSB-05OZ
		2 oz Bottle with brush applicator	VSB-2OZ

规格表

Vacseal® is a silicone based liquid resin system developed primarily for sealing leaks in high and UHV systems. Vacseal® will seal leaks as large as 4 micron liters per second on systems under evacuation. The sealant will repair larger leaks if the system is at atmospheric pressure. Weight loss and vapor pressure characteristics are truly outstanding. Vacseal® is extremely useful as a cement for sealing all kinds of optical windows and CRT glass to wire feed throughs. It will substantially reduce the IR reflectivity of metals and will produce higher emissivity levels for better heat transfer. The product can be used for the sealing of Brewster windows for lasers. And it can be used for more mundane applications such as the repairing of gauge tubes and also vacuum feed throughs. Vacseal, when sprayed on a surface, “dries” to a film that is optically transparent and exhibiting optical properties generally characteristic of clear silicone polymers.

VacSeal^® 是一种硅类液体树脂系统，最初是用来密封高真空和超高真空系统中的漏洞。最近，对其进行了重新调制，不再含有1级臭氧损耗化学品。在真空系统中，VacSeal每秒能密封4微米公升大的漏洞。在大气压下，该密封剂能修补更大的漏洞。重量损失和蒸气压特征极好。VacSeal是一种非常有用的接合剂，可用来密封各种光学窗口和CRT玻璃至送丝装置。VacSeal能充分减小金属的IR反射率，提高发射率水平，更好地传递热量。VacSeal可用来密封Brewster激光窗口。它也可以用于一些更平常的领域，如修理导管或真空送料装置。把VacSeal喷于表面，会“变干”成一层薄膜。薄膜看上去透明，具有透明硅树脂聚合体的外观特征。

The use of this product almost always results in reduced downtime, in some cases eliminates the need for expensive “permanent” repairs, and on occasion has been known to save an experiment in progress (an argument for keeping some on hand, “just in case”). Vacseal® has major potential for application as an adhesive at cryogenic temperatures as well as good radiation resistance. The sealant’s durability will survive the environment of space without adverse effect on the product or the spacecraft itself. For vacuum systems, just about where there is any kind of a joint is a potential application for Vacseal.

使用该产品可以减少工厂由于检修所需的停工期，有时候能免去昂贵的“永久性”维修的费用，或节省一些正在进行的实验（所有说有必要常备此产品，“以防万一”）。VacSeal 潜在的应用领域主要在于低温状态下的粘合剂和优良的辐射电阻。如果没有其它不利因素影响的话，该密封剂的耐用期适合应用于太空环境。在真空系统中，所有接合处，都是VacSeal的潜在应用领域。

Applications in space:

We are often times asked if Vacseal® is “qualified for use in space”. We wish we had a solid unambiguous answer to that question. Certainly, even after long periods of time, there is no weight loss of Vacseal. We have been told that Vacseal® currently is being used in space applications, such as on board satellites. We are told that it has been “approved” by some of the major firms in the aerospace industry and that it has been used on manned spacecraft. However, we do not have any specific documentation to which we could point where such usage has been documented. If you know of any such documentation, we would be greatly appreciative if you could share it with us, because we would be quite fast to put that additional information up for others to read and derive benefit. So in the mean time, if you are contemplating the use of Vacseal® in a space application, be sure you do the appropriate level of testing to make certain that Vacseal® would indeed work in your particular application

太空应用：

我们经常被问及VacSeal是否 "适合在太空领域使用"。我们希望能给予坚定的、毫不含糊的答案。的确，VacSeal经较长时间，也并没有重要损失。 我们知道VacSeal现在被应用于太空领域，如人造卫星，而且，其已经一些航空工业主要的公司“认可”。它已经被用于载人太空船。 然而，我们没有任何文件明确地载明这些用途。 如果您知道这种文件，并愿意同我们分享，我们将不胜感激，因为我们将 以最快的速度将这些信息提供给大家，让大家受益。同时，如果您意欲在太空领域使用VacSeal，请做适当的测试，以确定VacSeal适合您的需要。

Temperature Extremes:

One can assume product use to be in the temperature range of -200 to 450°C. At or about 400°C, in air, Vacseal® will start to oxidize, ultimately leaving only a white powder, but in vacuum, where there is no oxygen, it can be expected to operate up to about 450°C. We do not recommend taking the material to such extremes, but we have been told that others have found success, even at those temperatures. As with any other materials selection, some amount of testing must be done on the customer’s end to validate that the product will indeed work in your specific application. We don’t want this to sound like a major disclaimer, but we feel we cannot over-stress the importance of the customer making the final decision as to suitability, a decision being the result of your own testing.

温度范围：
通常可以认为该产品的温度范围为-200至450°C。在空气中，400°C左右，VacSeal 就开始氧化，最后只剩下白色粉末。但是在真空中，由于没有氧，VacSeal可耐温度高达450°C。我们并不推荐在这种极限温度下使用该产品，我们只是表明有人在这样极限的温度下成功地使用了该产品。同所有其它产品一样，用户必须自己测试以确定产品是否适合。我们并不希望这样的声明让人感觉像是拒绝承诺，只是我们不能忽视用户终端测试的的重要性。

The high temperature characteristics reported for Vacseal are possible because the product is a unique silicone and is not an epoxy or other organic based system which would degrade at far lower temperatures.

 因为该产品是一种独特的硅树脂，而不是环氧树脂或其他有机基系统，在较低的温度下会降解，所以报告中提到的高温特性是可能的。

Vacseal® has application as an adhesive at cryogenic temperatures as well as good radiation resistance. The sealant’s durability will survive the environment of space without adverse effect on the product or the spacecraft itself. The dried product will withstand repeated temperature cycling from liquid helium to 450°C.

Vacseal®作为一种粘合剂，在低温下具有良好的耐辐射性能。密封剂的耐久性可以在太空环境中使用，不会对产品或航天器本身产生不利影响。干燥后的产品可以承受从液氦到450°C的反复温度循环

Adhesion considerations:

Vacseal® will adhere literally to everything…..except, as we like to say, “running water”. Obviously, there are differences in adhesion between different materials, but for the most part, the adhesion is quite good on virtually all solid surfaces. But again, we have not tested the adhesion parameters on different materials quantitatively, so if adhesion is an important issue, be sure you devise your own kind of system-specific test to make sure that Vacseal® is indeed going to be the appropriate solution for your particular application. Just remember that Vacseal® was formulated to be a vacuum leak sealant, not specifically as an adhesive, but as we have learned over the years, a significant number of our customers are indeed using it as an adhesive. Unfortunately, because of the wide diversity of applications, we really don’t have further information on the use of Vacseal® as an adhesive. If you think you have such an application, we can only suggest that you might want to try it and after the appropriate testing, make some determination if it is the right “solution” for your specific case.

粘附性：

VacSeal几乎能粘附所有东西，除了“流水”。不同材料的粘附性是不一样的，但是，VacSeal对几乎所有固体表面的粘附性都非常好。然而，我们并没有不同材料的粘附性参数。如果粘附对您很重要的话，请自己做测试以确定VacSeal真正适合您的需要。

Use with hydrogen:

Vacseal® has been used to make seals for hydrogen gas and it has also be used to contain liquid hydrogen. The real question though is now well it does do this and on that point we have difficulty giving an unambiguous answer. With any container there will be some kind of leak rate, and this is going to be no exception, but in at least some applications, the use of Vacseal® seems to be quite acceptable.

用于密封氢：
VacSeal 被用来密封氢气和液态氢。现在的问题是它能完全密封吗？我们难以给出肯定的答案。任何容器都有某种程度的泄漏率，无一例外。但至少在很多应用领域，VacSeal的防泄露程度都是非常可以接受的。

Use in threaded joints:

Assuming the application is with a UHV (ultra high vacuum) system, and of course, the use of such joints in a UHV system is generally discouraged, in theory it could be used. Indeed Vacseal® has been used with threaded joints but not for UHV applications. The connection must be made “wet” and once the Vacseal® has started to cure, making the joint will become all that much more difficult, and the end result will probably be found to be less than satisfactory. The reason is that Vacseal® cures by evaporation of the solvent, yet some amount of solvent is required to make the polymer flow as a liquid into the crevices of the joint. High vacuum joints pose particularly frustrating issues, since the tendency is for the curing to begin at the outside and progress inward. The cured portion of the joint then acts as a barrier to the further evaporation of the solvent, and the result is that there is a very slow rate of solvent evaporation for a very long time, possibly years.

用于丝扣接头：
如果要在超高真空系统中使用丝扣接头，通常会被否决，虽然在理论上是可行的。事实上，VacSeal已经应用于丝扣接头，只是不在超高真空系统中应用。连接处必须是“湿的”，一旦 VacSeal开始作用，接合就变得非常困难，结果很可能不能使人满意。原因在于VacSeal通过溶剂蒸发进行接合，但聚合体仍然需要一些溶剂来促使其流入接合处的裂缝里。高真空接合是个非常困难的问题，因为接合是从表面开始，而在内部进行的。已经接合好的部分 就会阻碍溶剂的进一步蒸发，导致溶剂的蒸发速度非常慢，蒸发时间非常长，有时候可能要好些年。 

Removal of Vacseal:

Unlike other vacuum sealing products, the resulting polymer formed can be removed with a number of hydrocarbon solvents. The uncured polymer can be wiped away or otherwise removed with toluene, whereas the cured polymer requires something stronger, such as methyl ethyl ketone (MEK), or in extreme cases, methylene chloride. For applications not requiring high cleanliness, many common paint or lacquer thinners will work equally as well. However, common sense must always prevail, and if the Vacseal® is to be removed from a plastic substrate, for example, then some careful testing must be done first, in order to make sure that the solvent does not damage the underlying plastic

VacSeal的清除：
不象其它真空密封产品，形成的聚合体可以用一些烃类溶剂清除。尚未处理的聚合体可以擦去或用甲苯清除，而已经处理的聚合体需要一些更强的溶剂，如甲基乙基酮（MEK），或在极端的情况下，使用二氯甲烷。如果对清洁程度要求不高的话，很多普通的涂料或漆的稀释剂也可以用作清除剂。然而，如果要从塑料底层上清除VacSeal，必须做仔细的测试，以确定清除剂不会损害到底层的塑料。

Product shelf-life and stability:

Vacseal® has a limited shelf life. On the shelf while still in unopened bottles, and being stored at room temperature and out of direct sunlight, the shelf life could be expected to be a minimum of three years. However the liquid product in quart cans has a shelf life of only three months. Hence be sure to give serious thought to the purchase Vacseal® in bulk quantities. Unless the product is destined for use almost immediately, we would recommend the purchase of the smaller bottles instead of the individual larger bottles or bulk cans. Shelf life of the product in aerosol cans is less than that in bottles.

产品保存期限和稳定性：
VacSeal 的保存期限是有限的。在室温状态，无阳光直射，未开瓶的VacSeal能保存至少三年以上。然而，夸脱罐装的该液体产品保存期限仅为三个月。因此，在购买时，请认真考虑是否购买大瓶。除非您购买以后马上使用，否则我们会推荐购买小瓶代替大瓶或散装罐。产品在气溶胶罐中的保存期限比瓶装的要短。